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{\title Original file was misc4.tex}
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{\pard\plain\s20\qc\sb240\sa240\b\f0\fs36\sl240\slmult1 \fi0 An introduction to {\plain T{\dn7 E}X} and friends\par
\pard\plain\s21\qc\sa120\f0\fs24\sl240\slmult1 \fi360 Gavin Maltby\par
\pard\plain\s21\qc\sa120\f0\fs24\sl240\slmult1 \fi360 November 1992\par
\pard\plain\s80\ql\sb240\sa120\keepn\f0\b\fs24\sl240\slmult1 \fi0  Contents\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 \par
{\field{\*\fldinst TOC \\o "1-3" }{\fldrslt }}
\page
\pard\plain\s80\ql\sb240\sa120\keepn\f0\b\fs24\sl240\slmult1 \sb60 \fi0  List of Tables\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 \par
{\field{\*\fldinst TOC \\f t }{\fldrslt }}
\page
\pard\plain\ql\sb240\sa120\keepn\f0\b\fs40\sl240\slmult1 \sb60 \fi0 Chapter 1\par
\pard\plain\s2\ql\sb240\sa120\keepn\f0\b\fs40\sl240\slmult1 \sb240 \fi0 Getting acquainted with {\plain T{\dn7 E}X}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0 {\plain T{\dn7 E}X} is well known to be {\i the} typesetting package, and a vast cult of {\plain T{\dn7 E}X} lovers has evolved. But to the beginning {\plain T{\dn7 E}X} user, or to someone wondering if they should bother changing to {\plain T{\dn7 E}X}, it is often not clear what all the fuss is about. After all, are not both WordPerfect and Ventura Publisher capable of high quality output? Newcomers have often already seen what {\plain T{\dn7 E}X} is capable of (many books, journals, letters are now prepared with {\plain T{\dn7 E}X}) and so expect to find a tremendously powerful and friendly package. In fact they {\i do}, but that fact is well hidden in one\rquote s initial {\plain T{\dn7 E}X} experiences. In this chapter we describe a little of what makes {\plain T{\dn7 E}X} great, and why other packages cannot even begin to compete. Be warned that a little patience is required\emdash {\plain T{\dn7 E}X}\rquote s virtues are rather subtle to begin with. But when the penny drops, you will wonder how you ever put up with anything different.\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 1.1  The spirit of {\plain T{\dn7 E}X}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 In order to really appreciate {\plain T{\dn7 E}X} one needs to get a feel for what I call the \ldblquote spirit\rdblquote  of {\plain T{\dn7 E}X}. When {\plain T{\dn7 E}X} appears to be making me work overtime to achieve something that I think ought to be perfectly straightforward, consultation with the {\plain T{\dn7 E}X} spirit shows me the error of my ways.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 1.1.1  {\plain T{\dn7 E}X} is a typesetter, not a word-processor\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain T{\dn7 E}X} was designed with no limiting application in mind. It was intended to be able to prepare practically any document\emdash from a single page all-text letter to a full blown book with huge numbers of formulae, tables, figures etc. The size and the complexity of a {{\plain T{\dn7 E}X}}able document is limited only by hardware considerations. Furthermore, {\plain T{\dn7 E}X} seeks to achieve all this whilst setting typesetting standards of the highest order for itself. The expertise of generations of professional printers has been captured in {\plain T{\dn7 E}X}, and it has been taught all the tricks of the trade.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Historically, printers prepared a document by placing metal characters in a large tray and arranging and binding them to form a page. This was very precisely done, but the ultimate precision was limited because of the mechanical nature of things and by time considerations. {\plain T{\dn7 E}X} prepares a page in an analogous manner (putting your characters and formulae into \ldblquote boxes\rdblquote  which are then \ldblquote glued\rdblquote  together to form the page), but has the advantage of enormous precision because placement calculations are performed by computer. Indeed, {\plain T{\dn7 E}X}\rquote s internal unit (the \ldblquote scaled point\rdblquote ) is about one-hundredth of the wavelength of natural light!\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 \ldblquote But conventional word processors run on computers , too\rdblquote , you object. Yes, but their fundamental limitation is that they try to \ldblquote keep up\rdblquote  with you and \ldblquote typeset\rdblquote  your document as you type. This means that it can only make decisions at a local level (eg, it decides where to break a line just as you type the end of the line). {\plain T{\dn7 E}X}\rquote s secret is that it waits until you have typed the {\i whole} document before it typesets a single thing! This means that {\plain T{\dn7 E}X} can make decisions of a global nature in order to optimise the aesthetic appeal of your document. It has been taught what looks good and what looks bad (having been given a measure of the \ldblquote badness\rdblquote  of various possibilities) and makes choices for your document that are designed to make it \ldblquote minimally bad\rdblquote .\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 But {\plain T{\dn7 E}X}\rquote s virtues run much deeper than that, which is just as well because it is possible to get satisfactory, though imperfect, results from some word processors. One of {\plain T{\dn7 E}X}\rquote s strongest points is its ability to typeset complicated formulae with ease. Not only does {\plain T{\dn7 E}X} make hundreds of special symbols easily accessible, it will lay them out for you in your formulae. It has been taught all the spacing, size, font, \u8230?conventions that printers have decided look best in typeset formulae. Although, of course, it doesn\rquote t understand any mathematics it knows the grammar of mathematics\emdash it recognises binary relations, binary operators, unary operators, etc. and has been taught how these parts should be set. It is consequently rather difficult to get an equation to look bad in {\plain T{\dn7 E}X}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Another advantage of compiling a document after it is typed is that cross-referencing can be done. You can label and refer back to chapters, sections, tables etc. by {\i name} rather than absolute number, and {\plain T{\dn7 E}X} will number and cross-reference these for you. Similarly, it will compile a table of contents, glossary, index and bibliography for you.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Essential to the spirit of {\plain T{\dn7 E}X} is that {\i it formats the document whilst you just take care of the content}, making for increased productivity. The cross-referencing just mentioned is just part of this. Many more labour-saving mechanisms are provided for through {\i style files}. These are generic descriptions of classes of documents, teaching {\plain T{\dn7 E}X} just how each class likes to be formatted. This is taught in terms of font preferences, default page sizes, placement of title, author, date, etc. For instance, a {\i0\scaps0\b0\f3 paper} style file could teach {\plain T{\dn7 E}X} that when typesetting a theorem it should embolden the part that states the theorem number and typeset the text of the theorem statement in slanted Roman typeface (as in many journals). The typist simply provides and indication that a theorem is being stated, and then types the text of the theorem {\i without} bothering to choose any fonts or do any formatting\emdash all that is done by the style file. Style files exist for all manner of document\emdash letters, articles, papers, books, proceedings, review articles, and so on.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 In addition to style files, there are {\i macro packages}. A {\i macro} is just a definition of a new {\plain T{\dn7 E}X} command in terms of existing ones. Don\rquote t think small when you think of macros! When typing a document that has a lot of repetition in it, say the same expression is used again and again in different different equations, you can define a macro in your document to abbreviate that expression. But macros can teach {\plain T{\dn7 E}X} how to typeset all sorts of complicated structures, not just parts of an equation. Many macro packages (files that are just collections of definitions) have been written to teach {\plain T{\dn7 E}X} all sorts of applications. There are specialist maths packages ({\plain {\i AmS}-T{\dn7 E}X}, {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X}), general purpose packages ({\plain L{\up6\fs19 A}T{\dn7 E}X}), packages for setting tree diagrams, Feynmann diagrams, languages like Chinese, Arabic and Ancient Greek, orchestral scores, and many, many more. All these are freely available, a spin-off of the giant {\plain T{\dn7 E}X} cult.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Another facet of the design of {\plain T{\dn7 E}X} allows it to use practically {\i any} output device. In fact, {\plain T{\dn7 E}X} doesn\rquote t talk to any printers, screens, phototypesetters at all! Instead, when a document is compiled a {\i device independent} ({\i0\scaps0\b0\f3 .dvi}) is produced\emdash {\plain T{\dn7 E}X} does not compile with any particular output device in mind. Printer drivers are then invoked on this {\i0\scaps0\b0\f3 .dvi} file and, in consultation with the font data for that printer, produce output suitable for the particular device. You can choose an HP Laserjet driver, or an Apple LaserWriter driver, or a dot matrix driver etc. All use the same {\i0\scaps0\b0\f3 .dvi} file as input (and remember the material in there is set to enormous accuracy) and attempt to image that file on the particular device as faithfully as possible. If you are using a top of the line laser printer or phototypesetter, then {\plain T{\dn7 E}X}\rquote s massive internal precision will not be wasted. Alternatively, a dot matrix printer will give a coarse approximation of the ideal image that is suitable only for proof-reading. In addition to portability, these {\i0\scaps0\b0\f3 .dvi} files help ensure that there are very few printing surprises when you move from one device to another: how many times has your favourite word-processor made you reformat a document when you wish to change printers?\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 There are many other motivations one could cite for the superiority of {\plain T{\dn7 E}X}. But it is time that we started to get our hands dirty. One last comment: {\plain T{\dn7 E}X} was not designed to supplant secretaries and professional printers\emdash it was designed to aid them in their work and, in the words of the {\plain T{\dn7 E}X} designer Donald Knuth, allow them to \ldblquote go forward and create masterpieces of the publishing art\rdblquote .It also allows those who generate the material to be typeset\emdash mathematicians, physicists, computer scientists, etc\emdash to prepare their own documents in a language that is intimately linked to the language we use for writing such material.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The novice reader will still have no idea of what a {\plain T{\dn7 E}X} source file looks like. Indeed, why do we keep referring to it as a {\i source file}? The fact of the matter is that {\plain T{\dn7 E}X} is essentially a {\i programming language}. Just as in any compiled language (e.g., Pascal, C) one prepares a source file and submits it to the compiler which attempts to produce an object file ({\i0\scaps0\b0\f3 .dvi} file in the {\plain T{\dn7 E}X} case). To learn {\plain T{\dn7 E}X} is to learn the command syntax of the commands that can be used in the source file.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 1.1.2  Typical {\plain T{\dn7 E}X} interfaces\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain T{\dn7 E}X} was designed to run on a multitude of computers. It is therefore the case that the documentation for {\plain T{\dn7 E}X} and its \ldblquote friends\rdblquote  {\plain L{\up6\fs19 A}T{\dn7 E}X}, {\plain {\i AmS}-T{\dn7 E}X}, etc. is not computer specific. Only command syntax is described\emdash i.e., the content of your source file\emdash but few details of how to get from there to a printout are given. Those details are left to site-specific documents.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The average user loses little in using {\plain T{\dn7 E}X} on, say, a PC rather than on a bigger machine. Indeed, compilation times on the new PCs begin to rival those on a Sun Sparc Station 2 (no slouch). Running on top of DOS can cause memory problems when very large documents are being prepared. That aside, the quality of the document is not affected because of the careful design of {\plain T{\dn7 E}X}\emdash whether you work on a a machine with massive floating point precision or a modest XT the {\i0\scaps0\b0\f3 .dvi} files produced on compilation will be identical; and when those files are submitted to printer equivalent printer drivers (say for an HP LaserJet III attached to a Sun in one case and a PC in the other) the output will be identical because the font information they draw on is identical.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 By the nature of {\plain T{\dn7 E}X} most time is spent editing the source document (before submitting it for compilation). No special interface is necessary here, you just use your favourite text editor (perhaps customising it to enhance {{\plain T{\dn7 E}X}}nical typing. Thus {\plain T{\dn7 E}X} user interfaces are usually small and simple, often even missing. One frequently uses {\plain T{\dn7 E}X} at command line level, just running the editor, compiler etc. as you need them. Sometimes a {{\plain T{\dn7 E}X}}shell program is present, which runs these for you when you choose various menu options.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Whatever the interface, there are just a few basic steps to preparing a document: {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 1.\tab
Choose a document style to base your document on (e.g., letter, article). \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 2.\tab
Glance through the material you have to type, and decide what definitions might be made to save you a lot of time. Also, decide on the overall structure of the prospective document (e.g., will the largest sectional unit be a chapter or a part?). If you are going to compose as you type, then pause a moment to think ahead and plan the structure of your document. The importance of this step cannot be overstressed, for it makes clear in {\i your} mind what you want from {\plain T{\dn7 E}X}. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 3.\tab
Prepare your input file, specifying only the content and the logical structure (parts, sections, theorems,...) thereof and forgetting about formatting details. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 4.\tab
Submit your input, or source, file to the {\plain T{\dn7 E}X} compiler for compilation of a {\i0\scaps0\b0\f3 .dvi} file. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 5.\tab
If the compiler finds anything in your source file strongly objectionable, say incorrect command syntax, then return to editing. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 6.\tab
Run a {\i previewer} to preview your compiled document on the screen. Resolution is only limited by your screen, and can be very good indeed on some modern monitors. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 7.\tab
Go back to editing your document until glaring errors have been taken care of. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 8.\tab
Make a printout of your compiled document, and check for those errors that you failed to notice on the screen. \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Performing these steps may be effected through typing at the system prompt (barebones technique) or through choosing menu options in a {{\plain T{\dn7 E}X}}shell program. The latter will probably provide some conveniences to make your life easier.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 If you think this sounds like a lot of work, it is time that you consult with the {\plain T{\dn7 E}X} spirit! Sure your first couple of tries may be hesitant, but before long you\rquote ll find that you can take {\i less} time to prepare a document on {\plain T{\dn7 E}X} than on any other package.\par
\page
\pard\plain\ql\sb240\sa120\keepn\f0\b\fs40\sl240\slmult1 \fi0 Chapter 2\par
\pard\plain\s2\ql\sb240\sa120\keepn\f0\b\fs40\sl240\slmult1 \sb240 \fi0 Getting started with {\plain L{\up6\fs19 A}T{\dn7 E}X}\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb480 \fi0 2.1  Why start with {\plain L{\up6\fs19 A}T{\dn7 E}X}?\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 To answer this question we must say a little more about some of the macro packages we mentioned earlier.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The {\plain T{\dn7 E}X} typesetting system was designed by the eminent Stanford computer scientist Donald Knuth, on commission from the American Mathematical Society. It was designed with enormous care, to be ultimately powerful and maximally flexible. The enormous success of Knuth\rquote s design is apparent from the vast number of diverse applications {\plain T{\dn7 E}X} has found. In reading the following you must keep one thing clearly in mind: {\i there is only {\plain T{\dn7 E}X} language, and all the other packages whose names end in the suffix {-{\plain T{\dn7 E}X}} simply harness it\rquote s power via a whole lot of complicated macro definitions}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\plain T{\dn7 E}X} proper is a collection of around 300 so called {\i primitive} typesetting commands. These work at the very lowest level, affording enormous power. But to make this raw power manageable, some macros must be defined to tame raw {\plain T{\dn7 E}X} somewhat. The standard set of macros is called Plain {\plain T{\dn7 E}X}, and consists of about 600 macro definitions. It is clear that these definitions must be made in terms of {\plain T{\dn7 E}X} primitives, or in terms of previously made definitions. Plain {\plain T{\dn7 E}X}, however, is still no place for the timid. A strong working knowledge of {\plain T{\dn7 E}X} is still required to understand the ins and outs of Plain {\plain T{\dn7 E}X}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 In the few years after the initial {\plain T{\dn7 E}X} release (1982), the macro packages {\plain {\i AmS}-T{\dn7 E}X} and {\plain L{\up6\fs19 A}T{\dn7 E}X} were born. {\plain {\i AmS}-T{\dn7 E}X} was written by Michael Spivak, also on commission from the AMS. This package was designed to facilitate the preparation of the numerous books, journals, and review indices that fall under the auspices of the AMS and its affiliates. Married to the macro package was a style file\emdash the AMS preprint style. This was distributed along with the macro package, so that authors submitting to journals could use it in the preparation of their articles. The given style was based on the style used by the {\i Journal of the American Mathematical Society}, i.e., it conformed to their page sizes and typographical conventions. This meant that people around the world produced papers that were all based on the same style. The clever part is this: when a source file is submitted to a journal {\i other} than the {\i Journal of the AMS}, the journal staff simply substitute their style file for the AMS preprint style and the paper will appear completely different {\i with no other changes to the source code}! To create their style file, a journal just needed to tweak the standard AMS prepint style: for instance, the original preprint style places author addresses at the very end of a paper; If a journal wishes this to appear on the first page then they just modify their in-house version of the style file, and the change will be effected without having to change the file submitted by the author.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\plain L{\up6\fs19 A}T{\dn7 E}X} was written for more general usage. It lacks some of the mathematical finesse inherited by {\plain {\i AmS}-T{\dn7 E}X} from the vast experience of the AMS technical staff, but more than makes up for this in its ability to enhance the typesetting of letters, books, poetry, etc. {\plain L{\up6\fs19 A}T{\dn7 E}X} also scores high points for its enhanced command syntax.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 With {\plain {\i AmS}-T{\dn7 E}X} and {\plain L{\up6\fs19 A}T{\dn7 E}X} being released at around the same time (1984\endash 1985), there were born many {\plain {\i AmS}-T{\dn7 E}X} literate but {\plain L{\up6\fs19 A}T{\dn7 E}X} illiterate users, and conversely. {\plain L{\up6\fs19 A}T{\dn7 E}X} was easier to learn because of its more friendly syntax, and also provided powerful cross-referencing commands that {\plain {\i AmS}-T{\dn7 E}X} did not. So the AMS commissioned another project to furnish {\plain L{\up6\fs19 A}T{\dn7 E}X} users with the additional power of {\plain {\i AmS}-T{\dn7 E}X} while not compromising the {\plain L{\up6\fs19 A}T{\dn7 E}X} command syntax or cross-referencing commands. This resulted in the {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} macro package and associated style file for submission to journals.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\i That} is why we will kick off our {\plain T{\dn7 E}X} careers with {\plain L{\up6\fs19 A}T{\dn7 E}X}! It is easier to learn and provides many conveniences, and the user who requires additional mathematical typesetting prowess can easily move on to {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X}. Much of what we say will be true for {\plain T{\dn7 E}X} itself, but we shall regard {\plain L{\up6\fs19 A}T{\dn7 E}X} as the lowest common-denominator. By far the majority of {\plain L{\up6\fs19 A}T{\dn7 E}X} and {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} users will never have to learn \ldblquote raw\rdblquote  {\plain T{\dn7 E}X}, for they will be shielded from direct exposure by the numerous powerful macro packages. In the rare case that something way out of the ordinary is required, the local {\plain T{\dn7 E}X} guru can be consulted.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 \par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 2.2  {\plain L{\up6\fs19 A}T{\dn7 E}X} formats, and we compose\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 The {\i free form nature} of the input file is essential to the spirit of {\plain T{\dn7 E}X}. As we type, we do not concern ourselves with linebreaks and pagebreaks so much as the content of what we are typing. In fact, we\rquote ll see that {\plain T{\dn7 E}X} will choose nice line breaks even for bizarre looking input. This is just part of the concept of only having to describe the {\i logical} structure of the document to {\plain L{\up6\fs19 A}T{\dn7 E}X}, and not worry about nuisance-value formatting details. We inform {\plain L{\up6\fs19 A}T{\dn7 E}X} of the logical structure of our document by telling it when to begin a new paragraph, subsection, section, chapter, theorem, definition, remark, poem, list etc. When typing a particular element of the logical structure, we need pay little attention to how we lay our source file out.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 A consequence of this is that we have to go to a bit of effort to mess things up. Starting a new line, for instance, entails more than just pressing Return because {\plain L{\up6\fs19 A}T{\dn7 E}X} will just regard the next word you type as exactly that\emdash the next word in the paragraph. You have to specifically ask for a line to be terminated. Things like this may seem to be a bit of a nuisance, but it is a small price to pay for the automatic formatting that necessitated it. Further, such small inconveniences have been localised to rare events. I have, for instance, not once forced a new line up until this point in the present document.\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 2.3  Document styles\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We have explained the concept of a document style during our discussion of the virtues of {\plain T{\dn7 E}X} and the discussion of {\plain {\i AmS}-T{\dn7 E}X}. It remains to name a few, and indicate where they would be used. One {\i always} has to choose a document style when preparing a document with {\plain L{\up6\fs19 A}T{\dn7 E}X}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The basic document styles in {\plain L{\up6\fs19 A}T{\dn7 E}X} are {\i0\scaps0\b0\f3 letter}, {\i0\scaps0\b0\f3 article}, {\i0\scaps0\b0\f3 report}, and {\i0\scaps0\b0\f3 book}. Many more are available, but these few cover the majority of straightforward applications. This is because styles are not rigid\emdash you can impose your own parameter choices if you want. So one chooses the style that most closely approximates the document you have in mind, and performs some minor tweaks here and there. The {\i0\scaps0\b0\f3 article} style is used for documents that are to have the appearance of a journal or magazine article. The {\i0\scaps0\b0\f3 report} style is usually used for larger documents than the {\i0\scaps0\b0\f3 article} style. These styles really only differ in their choice of default page size, font, placement of title and author, sectional units, etc. and on how they format certain {\plain L{\up6\fs19 A}T{\dn7 E}X} constructs. You use the same {\plain L{\up6\fs19 A}T{\dn7 E}X} commands in each. Since the examples here will be small, we will choose to use the {\i0\scaps0\b0\f3 article} document style.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 There are a number of possible options with each document style. The syntax for choosing a document style follows. Don\rquote t worry if this leaves you with no idea of how to choose a document style, for we will soon be seeing some examples. Also, remember that an argument in square brackets is optional, and can omitted altogether (including the brackets). {\par
\i0\scaps0\b0\f3 \pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 \f3 \u92?documentstyle [{\i options}]\{{\i style}\} \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 where {\i style} is the main document style (eg {\i0\scaps0\b0\f3 report}) and the optional argument {\i options} is a list of document style options chosen from the following list: {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\i0\scaps0\b0\f3 11pt}\tab
chooses 11-point as the default font size for the document, instead of the default 10-point. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\i0\scaps0\b0\f3 12pt}\tab
chooses 12-point as the default font size. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\i0\scaps0\b0\f3 twoside}\tab
formats output as left and right pages, as in a book. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\i0\scaps0\b0\f3 twocolumn}\tab
produces two-column magazine like output. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\i0\scaps0\b0\f3 titlepage}\tab
applies to the {\i0\scaps0\b0\f3 article} style only, causing the title and abstract to appear on a page each. \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 In fact there are many, many more document style options but we won\rquote t mention any more here.\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 2.4  Preparing a non-mathematical document\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We assume that you have read the local guides to {\plain T{\dn7 E}X} at your site and have decided which system environment you want to work in. There you have been shown how to perform the steps required to produce a printed document from a {\plain L{\up6\fs19 A}T{\dn7 E}X} source file.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.1  Sentences and paragraphs\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Let\rquote s create our very first {\plain L{\up6\fs19 A}T{\dn7 E}X} document, which will consist of just a few paragraphs.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 As mentioned above, paragraph input is free-form. You type the words and separate them by spaces so that {\plain L{\up6\fs19 A}T{\dn7 E}X} can distinguish between words. For these purposes, pressing Return is equivalent to inserting a space\emdash it does not indicate the end of a line, but the end of a word. You tell {\plain L{\up6\fs19 A}T{\dn7 E}X} that a sentence has ended by typing a period followed by a space. {\plain L{\up6\fs19 A}T{\dn7 E}X} ignores extra spaces; typing three or three thousand will get you no more space between the words that these spaces separate than typing just one space. Finally, you tell {\plain L{\up6\fs19 A}T{\dn7 E}X} that a paragraph has ended by leaving one or more blank lines. In summary: {\plain L{\up6\fs19 A}T{\dn7 E}X} concerns itself only with the logical concepts end-of-word, end-of-sentence, and end-of-paragraph. Sounds complicated? An example should clear things up:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\documentstyle\{article\}
\par \\begin\{document\}
\par Words within a sentence are ended by spaces.  One space
\par between words  is     equivalent      to any number. We are only
\par interested in separating      one    word      from        the
\par next, not in formatting       the space between them.
\par For these purposes, pressing Return
\par at the end of a line
\par and starting a new word on the next line
\par just serves to separate
\par words, not to cut a line short.
\par The end of a sentence is indicated by a period
\par followed by one or more spaces.
\par 
\par The end of a paragraph is indicated by leaving a blank line.
\par All this
\par means that we can type without too much regard for layout, and
\par the typesetter will sort things out for us.
\par \\end\{document\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 produces the result\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 Words within a sentence are ended by spaces. One space between words is equivalent to any number. We are only interested in separating one word from the next, not in formatting the space between them. For these purposes, pressing Return at the end of a line and starting a new word on the next line just serves to separate words, not to cut a line short. The end of a sentence is indicated by a period followed by one or more spaces.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 \fs19 The end of a paragraph is indicated by leaving a blank line. All this means that we can type without too much regard for layout, and the typesetter will sort things out for us. }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Perhaps you would like to try running {\plain L{\up6\fs19 A}T{\dn7 E}X} on the above input. Consult your local guide for details.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Note that we have learned more than just how {\plain L{\up6\fs19 A}T{\dn7 E}X} recognises words, sentences and paragraphs. We\rquote ve also seen how to specify our choice of document style and how to tell {\plain L{\up6\fs19 A}T{\dn7 E}X} where our document begins and ends. Any material that is to be printed must lie somewhere between the declaration of {\b0\i0\scaps0\f3 \\begin\{document\}} and that of {\b0\i0\scaps0\f3 \\end\{document\}}. Definitions that are to apply to the entire document can be made before the declaration of the document beginning. The specification of document style must precede all other material.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 In future examples we won\rquote t explicitly display the commands that select document style and delimit the start and end of the document. But if you wish to try any of the examples, don\rquote t forget to include those commands. The {\i0\scaps0\b0\f3 article} document style will do for most of our examples. Of course, the preceding example looks not at all like an article because it is so short and because we specified no title or author information.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Most of what you need to know to type regular text is contained in the example above. When you consider that by far the majority of any document consists of straight text, it is obvious that {\plain L{\up6\fs19 A}T{\dn7 E}X} makes this fabulously straightforward. {\plain L{\up6\fs19 A}T{\dn7 E}X} will do all the routine work of formatting, and we simply get on with the business of composing.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\plain L{\up6\fs19 A}T{\dn7 E}X} does more than simply choose pleasing line breaks and provide natural spacing when setting a paragraph. Remember we said that {\plain T{\dn7 E}X} has inherited the knowledge of generations of professional printers\emdash well part of that knowledge includes being on the look-out for {\i ligatures}. These are combinations of letters within words which should be typeset as a single special symbol because they will \ldblquote clash\rdblquote  with each if this is not done. Have a look at these words {\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 flight, flagstaff, chaff, fixation \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 and compare them with these {\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 f{l}ight, f{l}agstaf{f}, chaf{f}, f{i}xation \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 See the difference? In the first set I let {\plain L{\up6\fs19 A}T{\dn7 E}X} run as it usually does. In the second I overruled it somewhat, and stopped it from creating ligatures. Notice how the \lquote fl\rquote , \lquote ff\rquote , and \lquote fi\rquote  combinations are different in the two sets\emdash in the former they form a single symbol (a ligature) and in the latter they are comprised of two disjoint symbols. There are other combinations that yields ligatures, but we don\rquote t have to bother remembering any of them because {\plain L{\up6\fs19 A}T{\dn7 E}X} will take care of these, too.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Notice, too, that {\plain L{\up6\fs19 A}T{\dn7 E}X} has been taught how to hyphenate the majority of words. It will hyphenate a word if it feels that the overall quality of the paragraph will be improved. For long words it has been taught several potential hyphenation positions.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\plain L{\up6\fs19 A}T{\dn7 E}X} also goes to a lot of trouble to try to choose pleasing page breaks. It avoids \ldblquote widows\rdblquote , which are single lines of a paragraph occurring by themselves at either the bottom of a page (where it would have to be the first line of a paragraph) or at the top of a page (where it would have to be the last). It also \ldblquote vertically justifies\rdblquote  your page so that all pages have exactly the same height, no matter what appears on them. As testimony to the success of the pagebreaking algorithm, I have (to this point) not once chosen a page break in this document.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.2  Punctuation\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Typists have a convention whereby a single space is left after a mid-sentence comma, and two spaces are left after a sentence-ending period. How do we enforce this if {\plain L{\up6\fs19 A}T{\dn7 E}X} treats a string of spaces just like a single one? The answer, unsurprisingly, is that we {\i don\rquote t}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par To have a comma followed by the appropriate space,  we simply
\par type a comma follows by at least one space. To end a sentence
\par we type a period with at least one following space.     No space will
\par be inserted if we type a comma or period followed straight away
\par by something other than a space, because there are times when
\par we won't require any space, i.e., we do what comes narurally.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will produce\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 To have a comma followed by the appropriate space, we simply type a comma follows by at least one space. To end a sentence we type a period with at least one following space. No space will be inserted if we type a comma or period followed straight away by something other than a space, because there are times when we won\rquote t require any space, i.e., we do what comes naturally. }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 {\plain L{\up6\fs19 A}T{\dn7 E}X} will produce suitable space after commas, periods, semi-colons and colons, exclamation marks, question marks etc. if they are followed by a space. In stretching a line to justify to the right margin, it also knows that space after a punctuation character should be more \ldblquote stretchable\rdblquote  than normal inter-word space and that space after a sentence-ending period should be stretched more than space after a mid-sentence comma. {\plain T{\dn7 E}X} knows the nature of punctuation if you stick to the simple rules outlined here. As we\rquote ve already said, those rules tell {\plain L{\up6\fs19 A}T{\dn7 E}X} how to distinguish consecutive words, sentences, phrases, etc.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Actually, there is more to ending sentences than mentioned above. Since {\plain L{\up6\fs19 A}T{\dn7 E}X} cannot speak English, it works on the assumption that {\i a period followed by a space ends a sentence unless the period follows a capital letter}. This works most of the time, but can fail. To get a normal inter-word space after a period that doesn\rquote t end a sentence, follow the period by a {\i control space}\emdash a {\b0\i0\scaps0\f3 \\ } (a {\i0\scaps0\b0\f3 \u92?} character followed by a space or return). Very rarely, you will have to force a sentence to end after a period that follows a capital letter (remember that {\plain L{\up6\fs19 A}T{\dn7 E}X} assumes this doesn\rquote t end a sentence). This is done by preceding the period with a {\b0\i0\scaps0\f3 \\@} command (you can guess from the odd syntax that this is rarely needed).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 It\rquote s time we saw some examples of this. After all, this is our first experience of {\i control symbols} (don\rquote t worry, there are many more to come).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par We must be careful not to confuse intra-sentence periods
\par with periods that end a sentence, i.e.\\ we must remember
\par that our task is to describe the sentence structure.  Periods
\par that the typesetter requires a little help with typically result
\par from abbreviations, as in etc.\\ and  others.  We have to work
\par somewhat harder to break a sentence after a capital letter,
\par but that shouldn't bother us to much if we keep up our intake
\par of vitamin E\\@.  All this goes for other sentence-ending
\par punctuation characters, so I could have said vitamin E\\@!
\par Fortunately, these are rare occurrences.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 results in\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 We must be careful not to confuse intra-sentence periods with periods that end a sentence, i.e. we must remember that our task is to describe the sentence structure. Periods that the typesetter requires a little help with typically result from abbreviations, as in etc. and others. We have to work somewhat harder to break a sentence after a capital letter, but that shouldn\rquote t bother us to much if we keep up our intake of vitamin E. All this goes for other sentence-ending punctuation characters, so I could have said vitamin E! Fortunately, these are rare occurrences. }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Quotation marks is another area where {\plain L{\up6\fs19 A}T{\dn7 E}X} will do some work for us. Keyboards have the characters {\b0\i0\scaps0\f3 `}, {\b0\i0\scaps0\f3 `}, and {\b0\i0\scaps0\f3 "} but we want to to have access to each of \lquote , \rquote , \ldblquote , and \rdblquote . So we proceed like this:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par `\\LaTeX' is no conventional word-processor, and
\par to to get quotes, like ``this'', we type repeated
\par ` and ' characters.  Note that modern
\par convention is that ``punctuation comes after
\par the closing quote character''.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which gives just what we want\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 \lquote {\plain L{\up6\fs19 A}T{\dn7 E}X}\rquote  is no conventional word-processor, and to to get quotes, like \ldblquote this\rdblquote , we type repeated {\i0\scaps0\b0\f3 \lquote } and {\i0\scaps0\b0\f3 \rquote } characters. Note that modern convention is that \ldblquote punctuation comes after the closing quote character\rdblquote . }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Very rarely, you have three quote characters together. Merely typing those three quote characters one-after-the-other is ambiguous\emdash how should they be grouped? You tell {\plain L{\up6\fs19 A}T{\dn7 E}X} how you want them grouped by inserting a very small space called {\b0\i0\scaps0\f3 \\,}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par ``\\,`Green ham' or `Eggs?'\\,'' is the question.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 gives the desired result\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 \ldblquote {\charscalex50\~}\lquote Green ham\rquote  or \lquote Eggs?\rquote {\charscalex50\~}\rdblquote  is the question. }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Since we have a typesetter at our disposal, we might as well use the correct dashes where we need them. There are three types of dash: the hyphen, the endash, and the emdash. A minus sign is not a dash.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Hyphens are typed as you\rquote d hope, just by typing a {\b0\i0\scaps0\f3 -} at the point in the word that you want a hyphen. Don\rquote t forget that {\plain L{\up6\fs19 A}T{\dn7 E}X} takes care of hyphenation that is required to produce pretty linebreaks. You only type a hyphen when you explicitly want one to appear, as in a combination like \ldblquote inter-college\rdblquote .\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 An endash is the correct dash to use in indicating number ranges, as in \ldblquote questions\~1\endash 3\rdblquote . To specify an endash you type two consecutive dashes on the keyboard, as in {\b0\i0\scaps0\f3 1--3}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 An emdash is a punctuation dash, used at the end of a sentence\emdash I tend to use them too much. To specify an emdash you type three consecutive dashes on the keyboard, as in \ldblquote \u8230?{\b0\i0\scaps0\f3 a sentence---I tend to}\u8230?\rdblquote .\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par Theorems 1--3 concern the semi-completeness
\par of our new construct---in the case that it
\par satisfies the first axiom.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 yields\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 Theorems 1\endash 3 concern the semi-completeness of our new construct\emdash in the case that it satisfies the first axiom. }}\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb180 \fi0 2.4.3  Ties\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 When you always remember to use {\i ties}, you know that you are becoming {{\plain T{\dn7 E}X}}nically inclined. Ties are used to prevent {\plain L{\up6\fs19 A}T{\dn7 E}X} from breaking lines at certain places. {\plain L{\up6\fs19 A}T{\dn7 E}X} will always choose line breaks that result in the most aesthetically pleasing paragraph as judged by its stringent rules. But because {\plain L{\up6\fs19 A}T{\dn7 E}X} does not actually understand the material it is setting so beautifully, it can make some poor choices.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 A {\i tie} is the character {\b0\i0\scaps0\f3 ~}. It behaves as a normal interword space in all respects {\i except} that the line-breaking algorithm will never break a line at that point. Thus\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par Dr. Seuss should be typed as Dr.~Seuss
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 for this makes sure that {\plain L{\up6\fs19 A}T{\dn7 E}X} will never leave the \lquote Dr\rquote  at the end of one line and put the \lquote Seuss\rquote  at the beginning of the next.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 One should try to get in to the habit of typing ties first-time, not after waiting to see if {\plain L{\up6\fs19 A}T{\dn7 E}X} will make a poor choice This will allow you to make all sorts of changes to your text without ever having to go back and insert a tie at a point that has migrated to the end of a line from the middle of a line as a result of those changes. Remember, of course, that the line-breaks \par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Here are some more examples of places where you should remember to place ties.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 \i0\scaps0\b0\f3 {\par
{\trowd\cellx4610\cellx9220
{\pard\intbl\ql Chapter{\b0\i0\scaps0\f3 ~}10\cell}
{\pard\intbl\ql Donald{\b0\i0\scaps0\f3 ~}E. Knuth\cell}
\row}
{\trowd\cellx4610\cellx9220
{\pard\intbl\ql Appendix{\b0\i0\scaps0\f3 ~}C\cell}
{\pard\intbl\ql width{\b0\i0\scaps0\f3 ~}2\cell}
\row}
{\trowd\cellx4610\cellx9220
{\pard\intbl\ql Figure{\b0\i0\scaps0\f3 ~}1\cell}
{\pard\intbl\ql function{\b0\i0\scaps0\f3 ~}f\cell}
\row}
{\trowd\cellx4610\cellx9220
{\pard\intbl\ql Theorem{\b0\i0\scaps0\f3 ~}2\cell}
{\pard\intbl\ql 1,{\b0\i0\scaps0\f3 ~}2, or{\b0\i0\scaps0\f3 ~}3\cell}
\row}
{\trowd\cellx4610\cellx9220
{\pard\intbl\ql Lemmas 3 and{\b0\i0\scaps0\f3 ~}4\cell}
{\pard\intbl\ql equals{\b0\i0\scaps0\f3 ~}5\cell}
\row}
} }\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 {\*\bkmkstart BMsec_reserved}2.4.4{\*\bkmkend BMsec_reserved}  Specially reserved symbols\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 In the sequel we will see that the the ten characters\par
{{\b0\i0\scaps0\f3 # $ % & ~ _ ^ \\ \{ \}}}are\~reserved\~for\~special\~use. Indeed, we have seen already that {\i0\scaps0\b0\f3 \u92?} and {\b0\i0\scaps0\f3 ~} are non-printing characters that perform special services (and we\rquote ll have a lot more to say about the use of {\i0\scaps0\b0\f3 \u92?}).But what if we need one of these special symbols to appear in our document? The answer for seven of the symbols is to precede them by a {\i0\scaps0\b0\f3 \u92?} character, so forming another {\i control symbol} (remember that {\i0\scaps0\b0\f3 \u92?} followed by a space was also a control symbol).{\fs19 {\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par It is not 100\\% straightforward to typeset the
\par characters \\$ \\& \\% \\_ \\\{ \\\}, but given the
\par enormous convenience of the use they are normally
\par reserved for this is a small price to pay.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 produces\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 It is not 100% straightforward to typeset the characters $ & % _ \{ \}, but given the enormous convenience of the use they are normally reserved for this is a small price to pay. }}\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb180 \fi0 2.4.5  So what are control symbols and words?\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 In typing a document, we can think of ourselves as being in one of two distinct modes. We are either typing {\i literal text} (which will just be set into neat paragraphs for us) or we are typing text that will be {\i interpreted} by {\plain L{\up6\fs19 A}T{\dn7 E}X} as an instruction to insert a special symbol or to perform some action. Thus we are either typing material that will go straight into the document (with some beautification), or we are giving commands to {\plain L{\up6\fs19 A}T{\dn7 E}X}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Some commands are implicit, in that we don\rquote t have to do anything much extra. For instance, we command {\plain L{\up6\fs19 A}T{\dn7 E}X} to end the present sentence by typing a period (that doesn\rquote t follow a capital letter). These are no so much commands as part of having to describe the logical structure of a document.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 A {\i control word} is something of the form {\b0\i0\scaps0\f3 \\commandname}, where the command name is a word made up only of the letters a to\~z and A to\~Z. A {\i control symbol} consists of a {\i0\scaps0\b0\f3 \u92?} followed by single symbol that is not a letter.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Here are some examples: {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
we have met the control space symbol {\b0\i0\scaps0\f3 \\ } before, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
the commands to set symbols like % and $ are control symbols \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\@} was a control symbol that told told {\plain L{\up6\fs19 A}T{\dn7 E}X} that the very next period did really end the sentence, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\LaTeX} is a control word that tell {\plain L{\up6\fs19 A}T{\dn7 E}X} to insert its own name at the current point, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\clubsuit} instructs that a {{\u9827*}} be inserted, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\pounds} inserts a \'a3 symbol, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\S} inserts a \'b6 symbol, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\em} makes the ensuing text {\i be emphasised}, \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 These examples show that control sequences can be used to access symbols not available from the keyboard, do some typesetting tricks like setting the word {\plain L{\up6\fs19 A}T{\dn7 E}X} the way it does, and change the appearance of whole chunks of text as with {\b0\i0\scaps0\f3 \\em}. We\rquote ll be meeting many more of these type of control sequences.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Another enormously powerful class of control sequences is those that accept {\i arguments}. They tell {\plain L{\up6\fs19 A}T{\dn7 E}X} to take the parts of text you supply and do something with them\emdash like make a fraction by setting the first argument over the second and drawing a line of the appropriate length between them. These are part of what makes {\plain L{\up6\fs19 A}T{\dn7 E}X} so powerful, and here are some examples.\par
{\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\chapter\{The beginning\}} causes {\plain L{\up6\fs19 A}T{\dn7 E}X} to start a new chapter with name \ldblquote The Beginning\rdblquote , number it in sequence, typeset the chapter heading in a suitable font, and make an entry in the table of contents, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\overline\{words\}} causes {{\field{\*\fldinst{ EQ  \\x\\to( {words}) }}{\fldrslt }}
} to be overlined, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\frac\{a+b\}\{c+d\}} sets the given two argument as a fraction, doing most of the dirty work for us: {{\field{\*\fldinst{ EQ  \\F({\i a}+{\i b},{\i c}+{\i d})}}{\fldrslt }}
}, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \bullet\tab
{\b0\i0\scaps0\f3 \\sqrt[5]\{a+b\}} typesets the fifth-root of {{\i a}+{\i b}}, like this: {{\field{\*\fldinst{ EQ  \\R(5,{\i a}+{\i b})}}{\fldrslt }}
}. The {\i0\scaps0\b0\f3 5} is in square brackets instead of braces because it is an optional argument and could be ommited all together (giving the default of square root), \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Mandatory arguments are given enclosed by braces, and optional arguments enclosed by square brackets. Each command knows how many arguments to expect, so you don\rquote t have to provide any indication of that.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We have actually jumped the gun a little. The above examples include examples of {\i mathematical} typesetting, and we haven\rquote t yet seen how to tell {\plain L{\up6\fs19 A}T{\dn7 E}X} that it is typesetting maths as opposed to some other random string of symbols that it doesn\rquote t understand either. We\rquote ll come to mathematical typesetting in good time.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We need to dwell on a {{\plain T{\dn7 E}X}}nicality for a moment. How does {\plain L{\up6\fs19 A}T{\dn7 E}X} know where the name of a control sequence ends? Will it accept both {\b0\i0\scaps0\f3 \\pounds3} and {\b0\i0\scaps0\f3 \\pounds 3} in order to set \'a33, and will {\b0\i0\scaps0\f3 \\emWalrus} and {\b0\i0\scaps0\f3 \\em Walrus} both be acceptable in order to get {\i Walrus}? The answer is easy when you remember that a control word consists only of alphabetic characters, and a control symbol consists of exactly one nonalphabetic character.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 So to determine which control sequence you typed, {\plain L{\up6\fs19 A}T{\dn7 E}X} does the following: {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 1.\tab
when a {\i0\scaps0\b0\f3 \u92?} character is encountered, {\plain L{\up6\fs19 A}T{\dn7 E}X} knows that either a control symbol or a control word will follow. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 2.\tab
If the {\i0\scaps0\b0\f3 \u92?} is followed by a nonalphabetic character, then {\plain L{\up6\fs19 A}T{\dn7 E}X} knows that it is a control {\i symbol} that you have typed. It then recognises which one it was, typesets it, and goes on to read the character which follows the symbol you typed. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 3.\tab
If the {\i0\scaps0\b0\f3 \u92?} is followed by an alphabetic character, then {\plain L{\up6\fs19 A}T{\dn7 E}X} knows that it is a control word that you have typed. But it has to work out where the name of the control word ends and where the ensuing text takes over again. Since only alphabetic characters are allowed, {\plain L{\up6\fs19 A}T{\dn7 E}X} reads everything up to just before that first nonalphabetic character as the control sequence name. Since it is common to delimit the end of a control word by a space, {\plain L{\up6\fs19 A}T{\dn7 E}X} will {\i ignore} any space that follows a control word, since you want that space treated as end-of-control-word space rather than interword space. \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 This has one important consequence: The character in the input file immediately after a control symbol will be \ldblquote seen\rdblquote  by {\plain L{\up6\fs19 A}T{\dn7 E}X}, but {\i any space following a control word will be discarded and never processed.} This does not affect one much if you adopt the convention of always typing a space after a control sequence name.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 There is a rare circumstance where this necessitates a little extra work and thought, which we illustrate by example:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par If we type a control word like \\LaTeX in the running text
\par then we must be cautious, because the string of spaces that
\par come after it will be discarded by the \\LaTeX\\ system.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which produces the output\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 If we type a control word like {\plain L{\up6\fs19 A}T{\dn7 E}X}in the running text then we must be cautious, because the string of spaces that come after it will be discarded by the {\plain L{\up6\fs19 A}T{\dn7 E}X} system. }}\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb180 \fi0 {\*\bkmkstart BMsec_groups}2.4.6{\*\bkmkend BMsec_groups}  Commands to change appearance\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We\rquote ve seen a little of how to access various symbols using control sequences and we mentioned the {\b0\i0\scaps0\f3 \\em} command to emphasise text, but we didn\rquote t see how to use them. We look here at commands that change the appearance of the text.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Each of the control words here is a directive rather than a control sequence that accepts an argument. This is because potential arguments consisting of text that wants to be emboldened or emphasised are very large, and it would be a nuisance to have to enclose such an argument in argument-enclosing braces.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 To delimit the area of text over which one of these commands has effect (its {\i scope}) we make that text into what is called a {\i group}. Groups are used extensively in {\plain L{\up6\fs19 A}T{\dn7 E}X} to keep effects local to an area, rather than affecting the whole document. Apart from enhancing usability, this also in a sense protects distinct parts of a document from each other.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The {\plain L{\up6\fs19 A}T{\dn7 E}X} commands for changing type style are given in table\~{\field{\*\fldinst{\lang1024 REF BMtab_typestyles \\* MERGEFORMAT }}{\fldrslt{2.1}}}, and those for changing type size are given in table\~{\field{\*\fldinst{\lang1024 REF BMtab_sizes \\* MERGEFORMAT }}{\fldrslt{2.2}}}. Commands for selecting fonts other than these are not discussed here.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \par
{\trowd\cellx1237\cellx2929\cellx3142\cellx4379\cellx6071\cellx6284\cellx7521\cellx9213
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\rm}}\cell}
{\pard\intbl\ql {Roman}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\it}}\cell}
{\pard\intbl\ql {\scaps0\b0\i italic}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\sc}}\cell}
{\pard\intbl\ql {\i0\b0\scaps Capitals}\cell}
\row}
{\trowd\cellx1237\cellx2929\cellx3142\cellx4379\cellx6071\cellx6284\cellx7521\cellx9213
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\em}}\cell}
{\pard\intbl\ql {\i Emphasised}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\sl}}\cell}
{\pard\intbl\ql {\scaps0\b0\i slanted}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\tt}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 typewriter}\cell}
\row}
{\trowd\cellx1237\cellx2929\cellx3142\cellx4379\cellx6071\cellx6284\cellx7521
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\bf}}\cell}
{\pard\intbl\ql {\i0\scaps0\b boldface}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\sf}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f2 sans serif}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 {Table {\*\bkmkstart BMtab_typestyles}2.1{\*\bkmkend BMtab_typestyles}: Commands for selecting type styles}{\field{\*\fldinst TC "2.1 Commands for selecting type styles" \\f t}{\fldrslt }}\par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi360 Each of the type style selection commands selects the specified style but does not change the size of font being used. The default type style is roman (you are reading a roman style font now). To change type size you issue one of the type size changing commands in table\~{\field{\*\fldinst{\lang1024 REF BMtab_sizes \\* MERGEFORMAT }}{\fldrslt{2.2}}}, which will select the indicated size in the currently active style. The release of {\plain L{\up6\fs19 A}T{\dn7 E}X} 3.0 (the present version is 2.09) will see the New Font Selection Scheme in place as a standard feature. This makes font matters much easier to deal with.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \par
{\trowd\cellx4250\clbrdrb\brdrs\cellx6165\clbrdrb\brdrs\cellx7691\clbrdrb\brdrs\cellx9217
{\pard\intbl\ql {size}\cell}
{\pard\intbl\qc {default (10pt)}\cell}
{\pard\intbl\qc {11pt option}\cell}
{\pard\intbl\qc {12pt option}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\tiny}}\cell}
{\pard\intbl\qr {5pt}\cell}
{\pard\intbl\qr {6pt}\cell}
{\pard\intbl\qr {6pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\scriptsize}}\cell}
{\pard\intbl\qr {7pt}\cell}
{\pard\intbl\qr {8pt}\cell}
{\pard\intbl\qr {8pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\footnotesize}}\cell}
{\pard\intbl\qr {8pt}\cell}
{\pard\intbl\qr {9pt}\cell}
{\pard\intbl\qr {10pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\small}}\cell}
{\pard\intbl\qr {9pt}\cell}
{\pard\intbl\qr {10pt}\cell}
{\pard\intbl\qr {11pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\normalsize}}\cell}
{\pard\intbl\qr {10pt}\cell}
{\pard\intbl\qr {11pt}\cell}
{\pard\intbl\qr {12pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\large}}\cell}
{\pard\intbl\qr {12pt}\cell}
{\pard\intbl\qr {12pt}\cell}
{\pard\intbl\qr {14pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\Large}}\cell}
{\pard\intbl\qr {14pt}\cell}
{\pard\intbl\qr {14pt}\cell}
{\pard\intbl\qr {17pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\LARGE}}\cell}
{\pard\intbl\qr {17pt}\cell}
{\pard\intbl\qr {17pt}\cell}
{\pard\intbl\qr {20pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\huge}}\cell}
{\pard\intbl\qr {20pt}\cell}
{\pard\intbl\qr {20pt}\cell}
{\pard\intbl\qr {25pt}\cell}
\row}
{\trowd\clbrdrr\brdrs\cellx4250\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6165\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7691\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { {\b0\i0\scaps0\f3 \\Huge}}\cell}
{\pard\intbl\qr {25pt}\cell}
{\pard\intbl\qr {25pt}\cell}
{\pard\intbl\qr {25pt}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 {Table {\*\bkmkstart BMtab_sizes}2.2{\*\bkmkend BMtab_sizes}: {\plain L{\up6\fs19 A}T{\dn7 E}X} size-changing commands.}{\field{\*\fldinst TC "2.2 {\plain L{\up6\fs19 A}T{\dn7 E}X} size-changing commands." \\f t}{\fldrslt }}\par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi360 The point-size option referred to in table\~{\field{\*\fldinst{\lang1024 REF BMtab_sizes \\* MERGEFORMAT }}{\fldrslt{2.2}}} is that specified in the {\b0\i0\scaps0\f3 \\documentstyle} command issued at the beginning of the input file. Through it you select that base (or default) font for your document to be 10, 11, or\~12 point Roman. If no options are specified, the default is 10-point Roman. The table shows, for instance, that if I issue a {\b0\i0\scaps0\f3 \\large} in this document for which I chose the {\i0\scaps0\b0\f3 12pt} document style option the result will be a {\fs29 14-point Roman typeface}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We mentioned that to restrict the scope of a type-changing command we will set the text to be affected off in a group. Let\rquote s look at an example of this.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par When we want to \{\\em emphasise\\/\} some text we
\par use the \{\\tt em\} command, and use grouping to
\par restrict the scope.  We can change font \{\\large sizes\}
\par in much the same way.  We can also obtain \{\\it italicised\},
\par \{\\bf emboldened\}, \{\\sc Capitals\} and \{\\sf sans serif\} styles.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 When we want to {\i emphasise} some text we use the {\i0\scaps0\b0\f3 em} command, and use grouping to restrict the scope. We can change font {\fs29 sizes} in much the same way. We can also obtain {\scaps0\b0\i italicised}, {\i0\scaps0\b emboldened}, {\i0\b0\scaps Capitals} and {\i0\scaps0\b0\f2 sans serif} styles. }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Notice how clever grouping allows us to do all that without once having to use {\b0\i0\scaps0\f3 \\rm} or {\b0\i0\scaps0\f3 \\normalsize}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 One more thing slipped into that example\emdash and {italic correction} {\b0\i0\scaps0\f3 \\/}. This is a very small amount of additional space that we asked to be inserted to allow for the change from sloping {\i emphasised} text to upright text, because the interword space has been made to look less substantial from the terminal sloping character. One has to keep an eye open for circumstances where this is necessary. See the effect of omitting an italic correction after the emphasised text earlier in this paragraph.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 One might expect, by now, that {\plain L{\up6\fs19 A}T{\dn7 E}X} would insert an italic correction for us. But there are enough occasions when it is not wanted, and there is no good rule for {\plain L{\up6\fs19 A}T{\dn7 E}X} to use to decide just when to do it for us. So the italic correction is always left up to the typist.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.7  Accents\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} provides accents for just about all occasions. They are accessed through a variety of control symbols and single-letter control worlds which accept a single argument\emdash the letter to be accented. These control sequences are detailed in table\~{\field{\*\fldinst{\lang1024 REF BMtab_accents \\* MERGEFORMAT }}{\fldrslt{2.3}}}.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \par
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\`\{o\}}}\cell}
{\pard\intbl\ql {\'f2}\cell}
{\pard\intbl\ql {(grave accent)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\'\{o\}}}\cell}
{\pard\intbl\ql {\'f3}\cell}
{\pard\intbl\ql {(acute accent)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\^\{o\}}}\cell}
{\pard\intbl\ql {\'f4}\cell}
{\pard\intbl\ql {(circumflex or \ldblquote hat\rdblquote )}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\"\{o\}}}\cell}
{\pard\intbl\ql {\'f6}\cell}
{\pard\intbl\ql {(umlaut or dieresis)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\~\{o\}}}\cell}
{\pard\intbl\ql {\'f5}\cell}
{\pard\intbl\ql {(tilde or \ldblquote squiggle\rdblquote )}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\=\{o\}}}\cell}
{\pard\intbl\ql {\u333o}\cell}
{\pard\intbl\ql {(macron or \ldblquote bar\rdblquote )}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\.\{o\}}}\cell}
{\pard\intbl\ql {\u559o}\cell}
{\pard\intbl\ql {(dot accent)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\u\{o\}}}\cell}
{\pard\intbl\ql {\u335o}\cell}
{\pard\intbl\ql {(breve accent)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\v\{o\}}}\cell}
{\pard\intbl\ql {\u466o}\cell}
{\pard\intbl\ql {(h\'e1\u269cek or \ldblquote check\rdblquote )}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\H\{o\}}}\cell}
{\pard\intbl\ql {\u337o}\cell}
{\pard\intbl\ql {(long Hungarian umlaut)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\t\{oo\}}}\cell}
{\pard\intbl\ql {{oo}}\cell}
{\pard\intbl\ql {(tie-after accent)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\c\{o\}}}\cell}
{\pard\intbl\ql {{\f5\u807\'b8}o}\cell}
{\pard\intbl\ql {(cedilla accent)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\d\{o\}}}\cell}
{\pard\intbl\ql {\u7885o}\cell}
{\pard\intbl\ql {(dot-under accent)}\cell}
\row}
{\trowd\cellx2567\cellx3805\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\b\{o\}}}\cell}
{\pard\intbl\ql {\u817_o}\cell}
{\pard\intbl\ql {(bar-under accent)}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 {Table {\*\bkmkstart BMtab_accents}2.3{\*\bkmkend BMtab_accents}: Control sequences for accents}{\field{\*\fldinst TC "2.3 Control sequences for accents" \\f t}{\fldrslt }}\par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi360 Thus we can produce \'f3 by typing {\b0\i0\scaps0\f3 \\'\{o\}}, \u462a by typing {\b0\i0\scaps0\f3 \\v\{a\}}, and P\'e1l Erd\'f6s by typing {\b0\i0\scaps0\f3 P\\'\{a\}l Erd\\"\{o\}s}. Take special care when accenting an {{\i i}} or a {{\i j}}, for they should lose their dots when accented. Use the control words {\b0\i0\scaps0\f3 \\i} and {\b0\i0\scaps0\f3 \\j} to produce dotless versions of these letters. Thus the best way to type to type \u277ex{\f5\u774u}\u305igent is {\b0\i0\scaps0\f3 \\u\{e\}x\\u\{\\i\}gent}.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.8  Over-ruling some of {\plain T{\dn7 E}X}\rquote s choices\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We\rquote ve seen that ties can be used to stop linebreaks occurring between words. But how can we stop {\plain L{\up6\fs19 A}T{\dn7 E}X} from hyphenating a particular word? More generally, how can we stop it from splitting any given group of characters across two lines. The answer is to make that group of characters appears as one solid {\i box}, through use of an {\b0\i0\scaps0\f3 \\mbox} command.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par For instance, if we wanted to be sure that the word
\par \{\\em currentitem\\/\} is not split across lines
\par then we should type it as \\mbox\{\\em currentitem\}.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 If for some reason we wish to break a line\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 in the middle of nowhere, preventing {\plain L{\up6\fs19 A}T{\dn7 E}X} from justifying that line to the prevailing right margin, the we use the {\b0\i0\scaps0\f3 \\newline} command. One can also use the abbreviated form {\b0\i0\scaps0\f3 \\\\}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par We start with a short line.\\newline
\par And  now we continue with the normal
\par text, remembering that where we press
\par Return in the input file probably won't
\par correspond to a line break in the final
\par document.  More short lines\\\\
\par are easy, too.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will produce the line breaks we want\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 We start with a short line.\line  And now we continue with the normal text, remembering that where we press Return in the input file probably won\rquote t correspond to a line break in the final document. More short lines\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 are easy, too. }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 A warning is in order: {\b0\i0\scaps0\f3 \\newline} must only end part of a line that is \ldblquote already set\rdblquote . It cannot be used to add additional space between paragraphs, nor to leave space for a picture you want to paste in. This is not to be awkward, but is just part of {\plain L{\up6\fs19 A}T{\dn7 E}X} holding up its end of the deal by making you have to specially request additional vertical space. This prevents unwanted extra space from entering your document.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Later we shall see how to impose our own choice of page size, paragraph indentation, etc. For now we will continue to accept those declared for us in the document style.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.9  Commenting your document\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 It is handy to be able to make comments to yourself in the source file for a document. Things like \ldblquote I must rewrite this section\rdblquote  and \ldblquote This is version 3 of the document\rdblquote  are likely. It would also be useful to be able to make the compiler ignore certain parts of the document at times. For this purpose we can use the {\b0\i0\scaps0\f3 %} character, for all text on an input line that is after a {\b0\i0\scaps0\f3 %} which is not part of an occurrence of the control symbol {\b0\i0\scaps0\f3 \\%} is discarded by the compiler. Here is an example:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par There was a 100\\% turnout today,
\par an all-time record.  %perhaps I should check this claim!
\par %Indeed, there are lots of unsubstantiated claims here!
\par This made for an extremely productive session.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will yields\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 There was a 100% turnout today, an all-time record. This made for an extremely productive session. }}\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb180 \fi0 2.4.10  Footnotes\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Inserting footnotes is easy\emdash {\plain L{\up6\fs19 A}T{\dn7 E}X} will position and number them for you. You just indicate {\i exactly} where the footnote marker should go, and provide the text of the footnote. The footnote text will be placed at the bottom of the present page in a somewhat smaller font, and be separated from the main text by a short horizontal rule{\cs62\super\chftn}
{\*\footnote\pard \s65\ql\fi-113\li397\lin397\f0\fs24{\cs62\super\chftn} See for yourself! It\rquote s easy when you don\rquote t have to do any work.}
 to conform with convention. The footnote in the last line was typed like this:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par ...rule\\footnote\{See for yourself! It's easy ...work.\} to conform
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 No space was typed between the {\i0\scaps0\b0\f3 rule} and the {\b0\i0\scaps0\f3 \\footnote}, because we want the footnote marker to appear right next to the last letter of the word.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Multiple footnotes{\cs62\super\chftn}
{\*\footnote\pard \s65\ql\fi-113\li397\lin397\f0\fs24{\cs62\super\chftn} Here is another footnote}
 are obtained just by using the {\b0\i0\scaps0\f3 \\footnote} command again and again.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.11  Topmatter\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We declare the title and author information using the {\b0\i0\scaps0\f3 \\title} and {\b0\i0\scaps0\f3 \\author} commands, each of which accept a single argument. Multiple authors are all listed in the argument of {\b0\i0\scaps0\f3 \\title}, separated by {\b0\i0\scaps0\f3 \\and}\rquote s. The {\b0\i0\scaps0\f3 \\date} command can be used to date a document. After we have declared each of these, we issue a {\b0\i0\scaps0\f3 \\maketitle} command to have them typeset for us. In the {\b0\i0\scaps0\f3 book} and {\b0\i0\scaps0\f3 article} document styles this will result in a separate page; in the {\b0\i0\scaps0\f3 article} style the \ldblquote top matter\rdblquote  will be placed at the top of the first page. The style files determine the placement and the choice of font.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\title\{A Thought for the Day\}
\par \\author\{Fred Basset \\and Horace Hosepipe\}
\par \\date\{November 1992\}
\par \\maketitle
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will produce something along the lines of\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {\fs34 A Thought for the Day}\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 \par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb60 \fi0 \fs19 Fred Basset{    }Horace Hosepipe\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 \par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb60 \fi0 \fs19 November 1992 \par
}}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 This topmatter must appear {\i after} the {\b0\i0\scaps0\f3 \\begin\{document\}} and before any other printing material.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.12  Sectioning commands\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 As part of our task of describing the logical structure of the document, we must indicate to {\plain L{\up6\fs19 A}T{\dn7 E}X} where to start sectional units. To do this we make use of the sectioning commands shown in table\~{\field{\*\fldinst{\lang1024 REF BMtab_sectioning \\* MERGEFORMAT }}{\fldrslt{2.4}}}.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 {\i0\scaps0\b0\f3  {\par
{\trowd\cellx2570\cellx5963\cellx9219
{\pard\intbl\ql {\u92?part}\cell}
{\pard\intbl\ql {\u92?subsection}\cell}
{\pard\intbl\ql {\u92?paragraph}\cell}
\row}
{\trowd\cellx2570\cellx5963\cellx9219
{\pard\intbl\ql {\u92?chapter}\cell}
{\pard\intbl\ql {\u92?subsubsection}\cell}
{\pard\intbl\ql {\u92?subparagraph}\cell}
\row}
{\trowd\cellx2570\cellx5963\cellx9219
{\pard\intbl\ql {\u92?section}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {}\cell}
\row}
} } \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 {Table {\*\bkmkstart BMtab_sectioning}2.4{\*\bkmkend BMtab_sectioning}: {\plain L{\up6\fs19 A}T{\dn7 E}X} sectioning commands}{\field{\*\fldinst TC "2.4 {\plain L{\up6\fs19 A}T{\dn7 E}X} sectioning commands" \\f t}{\fldrslt }}\par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi360 Each sectioning command accepts a single argument\emdash the section heading that is to be used. {\plain L{\up6\fs19 A}T{\dn7 E}X} will provide the section numbering (and numbering of subsections within sections, etc.) so there is no need to include any number in the argument. {\plain L{\up6\fs19 A}T{\dn7 E}X} will also take care of whatever spacing is required to set the new logical unit off from the others, perhaps through a little extra space and using a larger font. It will also start a new page in the case that a new chapter is begun.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The {\b0\i0\scaps0\f3 \\part} command is used for major subdivisions of substantial documents. The {\b0\i0\scaps0\f3 \\paragraph} and {\b0\i0\scaps0\f3 \\subparagraph} commands are, unfortunately confusing. They are used to section off a modest number of paragraphs of text\emdash they don\rquote t start new paragraphs (remember that that was done by leaving a blank line in our input file). The names were retained for historical reasons.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 It is always a good idea to {\i plan} the overall sectional structure of a document in advance, or at least give it a little thought. Not that it would be difficult to change your mind later (you could use the global replace feature of an editor, for instance), but so that you have a good idea of the structure that you have to describe to {\plain L{\up6\fs19 A}T{\dn7 E}X}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The sectioning command that began the present sectional unit of this document was\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {{\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 
\par \\subsection\{Sectioning commands\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 and that was all that was required to get the numbered section name and the table of contents entry.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 There are occasions when you want a heading to have all the appearance of a particular sectioning command, but shouldn\rquote t be numbered as a section in its own right or produce a table of contents entry. This can be achieved through using the {\i *-form} of the command, as in {\b0\i0\scaps0\f3 \\section*\{...\}}. We\rquote ll see that many {\plain L{\up6\fs19 A}T{\dn7 E}X} commands have such a *-form which modify their behaviour slightly.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Not only will {\plain L{\up6\fs19 A}T{\dn7 E}X} number your sectional units for you, it will compile a table of contents too. Just include the command {\b0\i0\scaps0\f3 \\tableofcontents} after the {\b0\i0\scaps0\f3 \\begin\{document\}} command and after the topmatter that should precede it.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.13  {\plain L{\up6\fs19 A}T{\dn7 E}X} environments\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Perhaps the most powerful and convenient concept in the {\plain L{\up6\fs19 A}T{\dn7 E}X} syntax is that of an {\i environment}. We will see most of the \ldblquote heavy\rdblquote  typesetting problems we will encounter can be best tackled by one or other of the {\plain L{\up6\fs19 A}T{\dn7 E}X} environments.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Some environments are used to {\i display} a portion of text, i.e. to set it off from the surrounding text by indenting it. The {\i0\scaps0\b0\f3 quote} and {\i0\scaps0\b0\f3 verse} environments are examples of these. The {\i0\scaps0\b0\f3 center} environment allows us to centre portions of text, while the {\i0\scaps0\b0\f3 flushright} environment sets small portions of text flush against the right margin.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 But the true power of {\plain L{\up6\fs19 A}T{\dn7 E}X} begins to show itself when we look at environments such as those that provide facilities for itemised or enumerated lists, complex tabular arrangements, and for taking care of figure and table positioning and captioning. What we learn here will also be applicable in typesetting some complicated mathematical arrangements in the next chapter.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 All the environments are begun by a {\i0\scaps0\b0\f3 \u92?begin{\{{\i name}\}}} command and ended by an {\i0\scaps0\b0\f3 \u92?end{\i \{name\}}}, where {\i name} is the environment name. These commands also serve as begin-group and end-group{\cs62\super\chftn}
{\*\footnote\pard \s65\ql\fi-113\li397\lin397\f0\fs24{\cs62\super\chftn} See section {\field{\*\fldinst{\lang1024 REF BMsec_groups \\* MERGEFORMAT }}{\fldrslt{2.4.6}}}}
 markers, so that all commands are local to the present environment\emdash they cannot affect text outside the environment.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We can also have environment embedded within environment within environment and so on, limited only by memory available on the computer. We must, however, be careful to check that each of these {\i nested} environments is indeed contained within the one just outside of it.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.14  {\i0\scaps0\b0\f3 em} environment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We start with a very simple environment, one which provides an alternative to the {\b0\i0\scaps0\f3 \\em} command. Remember that {\b0\i0\scaps0\f3 \\em} does not accept an argument; it applies to everything within its scope as dictated by the group within which it is used. This can be tricky if we wish to emphasise a large amount of text, for we may forget a group-delimiting brace and so upset the entire grouping structure of our document. In cases where we fear this might happen, we can proceed as follows.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{em\}
\par We must always be careful to match our group-delimiting
\par braces correctly.  If the braces in a document are unevenly
\par matched then \\LaTeX\\ will become confused because we will
\par have, in effect, indicated different scopes than we
\par intended for commands.
\par \\end\{em\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which will give\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {\i  We must always be careful to match our group-delimiting braces correctly. If the braces in a document are unevenly matched then {\plain L{\up6\fs19 A}T{\dn7 E}X} will become confused because we will have, in effect, indicated different scopes than we intended for commands. } }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Although {\plain L{\up6\fs19 A}T{\dn7 E}X} doesn\rquote t care too much for how we format our source file, it is obviously a good idea to lay it out logically and readably anyway. This helps minimise errors as well as aids in finding them. For this reason I have adopted the convention of always placing the environment {\b0\i0\scaps0\f3 \\begin} and {\b0\i0\scaps0\f3 \\end} commands on lines by themselves.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.15  {\i0\scaps0\b0\f3 quote} and {\i0\scaps0\b0\f3 quotation} environments\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 This environment can be used to display a part of a sentence or paragraph, or even several paragraphs, in such a manner that the material stands out from the rest of the text. This can be used to enhance readability, or to simply emphasise something. Its syntax is simple:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par Horace smiled and retaliated:
\par \\begin\{quote\}
\par \\em You can mock the non-WYSIWYG nature of \\TeX\\
\par all you like.  You don't understand that that is
\par precisely what makes \\TeX\\ enormously more powerful
\par than that lame excuse for a typesetter you use.
\par And I'll bet that from start to finish of preparing
\par a document I'm quicker than you are, even if you
\par do type at twice the speed and have the so-called
\par advantage of WYSIWYG.  In your case, what you see
\par is \{\\em all\\/\} you get!
\par \\end\{quote\}
\par and then continued with composing his masterpiece of the
\par typesetting art.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 produces the following typeset material:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {{\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 Horace smiled and retaliated: {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \li512\ri512\fi0 \fs19 \i You can mock the non-WYSIWYG nature of {\plain T{\dn7 E}X} all you like. You don\rquote t understand that that is precisely what makes {\plain T{\dn7 E}X} enormously more powerful than that lame excuse for a typesetter you use. And I\rquote ll bet that from start to finish of preparing a document I\rquote m quicker than you are, even if you do type at twice the speed and have the so-called advantage of WYSIWYG. In your case, what you see is {\i0 all} you get! \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 \fs19 and then continued with composing his masterpiece of the typesetting art. }}\par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 That is a much more readable manner of presenting Horace\rquote s piece of mind than embedding it within a regular paragraph. The {\i0\scaps0\b0\f3 quote} environment was responsible for the margins being indented on both sides during the quote. This example has also been used to show how the commands that begin and end an environment restrict the scope of commands issued within that environment: The {\b0\i0\scaps0\f3 \\em} at the beginning of the quote did not affect the text following the quote. We have also learned here that if we use {\b0\i0\scaps0\f3 \\em} within already emphasised text, the result is roman type\emdash and we don\rquote t require an italic correction here because the final letter of \lquote all\rquote  was not sloping to the right.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The {\i0\scaps0\b0\f3 quotation} environment is used in just the same way as the {\i0\scaps0\b0\f3 quote} environment above, but it is intended for setting long quotations of several paragraphs. It would be suitable for quoting a few paragraphs from the text of some speech, for instance. {\plain L{\up6\fs19 A}T{\dn7 E}X} treats the given text just like normal text that it has to set into paragraphs, except that it indents the margins a little.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.16  {\i0\scaps0\b0\f3 verse} environment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 This is provided to facilitate the setting of poetry. When within the {\i0\scaps0\b0\f3 verse} environment, we use {\b0\i0\scaps0\f3 \\newline} (or {\b0\i0\scaps0\f3 \\\\}) to end a line; and what would normally signify a new paragraph serves to indicate the start of a new stanza. Let\rquote s have a shot at some cheap poetry.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{verse\}
\par Roses are red\\\\
\par Violets are blue\\\\
\par I think \\TeX\\ is great\\\\
\par And so will you!
\par 
\par Roses are still red\\\\
\par Violets are still blue\\\\
\par I'm schizophrenic\\\\
\par And so am I.
\par \\end\{verse\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will produce the following stunningly-creative \ldblquote poem\rdblquote :\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li1134\fi0 \fs19 Roses are red\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li1134\fi0 \fs19 Violets are blue\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li1134\fi0 \fs19 I think {\plain T{\dn7 E}X} is great\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li1134\fi0 \fs19 And so will you!\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li1134\fi0 \fs19 Roses are still red\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li1134\fi0 \fs19 Violets are still blue\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li1134\fi0 \fs19 I\rquote m schizophrenic\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li1134\fi0 \fs19 And so am I. \par
}}}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 2.4.17  {\i0\scaps0\b0\f3 center} environment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 This environment allows the centring of consecutive lines of text, new lines being indicated by a {\b0\i0\scaps0\f3 \\\\}. If you don\rquote t separate lines with the {\b0\i0\scaps0\f3 \\\\} command then you\rquote ll get a centred paragraph the width of the page, which won\rquote t look any different to normal. If only one line is to be centred, then no {\b0\i0\scaps0\f3 \\\\} is necessary.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par The \{\\tt center\} environment takes care of the vertical
\par spacing before and after it, so we don't need to leave any.
\par \\begin\{center\}
\par If we leave no blank line after the\\\\
\par \{\\tt center\} environment\\\\
\par then the ensuing text will not\\\\
\par be regarded as part of a new\\\\
\par paragraph, and so will not be indented.\\\\
\par \\end\{center\}
\par 
\par In this case we left a blank line after the environment,
\par so the new text was regarded as starting a new paragraph.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 gives the following text\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 The {\i0\scaps0\b0\f3 center} environment takes care of the vertical spacing before and after it, so we don\rquote t need to leave any. {\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 If we leave no blank line after the\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {\i0\scaps0\b0\f3 center} environment\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 then the ensuing text will not\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 be regarded as part of a new\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 paragraph, and so will not be indented.\par
\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 \fs19 In this case we left a blank line after the environment, so the new text was regarded as starting a new paragraph. }}\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb180 \fi0 2.4.18  {\i0\scaps0\b0\f3 flushright} and {\i0\scaps0\b0\f3 flushleft} environments\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 The {\i0\scaps0\b0\f3 flushright} environment causes each line to be set with its last character against the right margin, without trying to stretch the line to to current text width. The {\i0\scaps0\b0\f3 flushleft} environment is similar.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par We can stop \\LaTeX\\ from justifying each line to both the
\par left and the right margins.
\par \\begin\{flushright\}
\par The \{\\tt flushright\} environment is\\\\
\par used for text with an even right margin\\\\
\par and a ragged left margin.
\par \\end\{flushright\}
\par \\begin\{flushleft\}
\par and the \{\\tt flushleft\} environment is\\\\
\par used for text with an even left margin\\\\
\par and a ragged right margin.
\par \\end\{flushleft\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 gives the desired display\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 We can stop {\plain L{\up6\fs19 A}T{\dn7 E}X} from justifying each line to both the left and the right margins. {\par
\pard\plain\s8\qr\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 The {\i0\scaps0\b0\f3 flushright} environment is\par
\pard\plain\s8\qr\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 used for text with an even right margin\par
\pard\plain\s8\qr\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 and a ragged left margin. \par
}{\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 and the {\i0\scaps0\b0\f3 flushleft} environment is\par
\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 used for text with an even left margin\par
\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 and a ragged right margin. \par
}}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 One must be wary not to lapse into \ldblquote word-processing\rdblquote  mode when using these environments. Remember that pressing return at the end of a line in the input file does not serve to end the current line there, but just to indicate the end of another word. We have to use the {\b0\i0\scaps0\f3 \\\\} command to end a line.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.19  {\i0\scaps0\b0\f3 verbatim} environment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We can simulate typed text using the {\i0\scaps0\b0\f3 verbatim} environment. The {\b0\i0\scaps0\f3 \\tt} (typewriter text) type style can be used for simulating typed words, but runs into trouble if one of the characters in the simulated typed text is a specially reserved {\plain L{\up6\fs19 A}T{\dn7 E}X} character. For instance, {\b0\i0\scaps0\f3 \{\\tt type \\newline\}} would not have the desired effect because {\plain L{\up6\fs19 A}T{\dn7 E}X} would interpret the {\b0\i0\scaps0\f3 \\newline} is an instruction to start a new line.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The {\i0\scaps0\b0\f3 verbatim} environment allows the simulation of multiple typed lines. {\i Everything} within the environment is typeset in typewriter font exactly as it appears in our source file\emdash obeying spaces and line breaks as in the source file and not recognising the existence of any special symbols.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\i0\scaps0\b0\f3 \pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \f3 \fs19 \u92?begin\{verbatim\}\par
\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \f3 \fs19 In the verbatim environment we can type anything\par
\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \f3 \fs19 we like.\par
\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \f3 \fs19 So we don\rquote t need to look out for uses of %, $, & etc,\par
\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \f3 \fs19 nor will control sequences like \u92?newline have any\par
\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \f3 \fs19 effect.\par
\pard\plain\s10\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \f3 \fs19 \u92?end\{verbatim\} \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 will produce the simulated input text\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par In the verbatim environment we can type anything
\par we like.
\par So we don't  need to look out for uses of %, $, & etc,
\par nor will control sequences like \\newline have any 
\par effect.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 The only thing that cannot be typed in the {\i0\scaps0\b0\f3 verbatim} environment is the sequence {\b0\i0\scaps0\f3 \\end\{verbatim\}}. You might notice that I still managed to simulate that control sequence above. One can always get what you want in {\plain T{\dn7 E}X}, perhaps with a little creativity.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 If we want only to simulate a few typed words, such as when I say to use {\b0\i0\scaps0\f3 \\newline} to start a new line, then the {\b0\i0\scaps0\f3 \\verb} command is used. This command has a slightly odd syntax, pressed upon it by the use for which it was intended. It cannot accept an argument, because we may want to simulate typed text that is enclosed by {\b0\i0\scaps0\f3 \{braces\}}. What one does is to choose any character that is {\i not} in the text to be simulated, and use a pair of these characters as \ldblquote argument delimiters\rdblquote . I usually use the {\b0\i0\scaps0\f3 @} or {\b0\i0\scaps0\f3 "} charachters, as I rarely have any other uses for them. Thus\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 use {\b0\i0\scaps0\f3 \\%} to obtain a % sign }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 is typed as\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par use \\verb"\\%" to obtain a \\% sign
\par \par
}}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb180 \fi0 2.4.20  {\i0\scaps0\b0\f3 itemize}, {\i0\scaps0\b0\f3 enumerate}, {\i0\scaps0\b0\f3 description} environments\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} provides three predefined list-making environment, and a \ldblquote primitive\rdblquote  list environment for designing new list environments of your own. We shall just describe the predefined ones here.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 There is delightfully little to learn in order to be able to create lists. The only new command is {\b0\i0\scaps0\f3 \\item} which indicates the beginning of a new list item (and the end of the last one if this is not the first item). This command accepts an optional argument (which means you\rquote d enclose it in square brackets) that can be used to provide an item label. If no optional argument is given, then {\plain L{\up6\fs19 A}T{\dn7 E}X} will provide the item label for you; in an {\i0\scaps0\b0\f3 itemize} list it will bullet the items, in an {\i0\scaps0\b0\f3 enumerate} list it will number the items, and in a list of {\i0\scaps0\b0\f3 description}s the default is to have no label (which would look a bit odd, so you\rquote re expected to use the optional argument there).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Remember that {\b0\i0\scaps0\f3 \\item} is used to separate list items; it does not accept the list item as an argument. \par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{itemize\}
\par \\item an item is begun with \\verb@\\item@
\par \\item if we don't specify labels, then
\par   \\LaTeX\\ will bullet the items for us
\par \\item I indent lines after the first in the
\par   input file, but that is just to keep things
\par   readable.  As always, \\LaTeX\\ ignores additional
\par   spaces.
\par 
\par \\item a blank line between items is ignored, for
\par   \\LaTeX\\ is responsible for spacing items.
\par \\item \\LaTeX\\ is in paragraph-setting mode when
\par   it reads the text of an item, and so will
\par   perform all the usual functions
\par \\end\{itemize\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 produces the following itemised list:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19  {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 \bullet\tab
an item is begun with {\i0\scaps0\b0\f3 \u92?item}\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 \bullet\tab
if we don\rquote t specify labels, then {\plain L{\up6\fs19 A}T{\dn7 E}X} will bullet the items for us \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 \bullet\tab
I indent lines after the first in the input file, but that is just to keep things readable. As always, {\plain L{\up6\fs19 A}T{\dn7 E}X} ignores additional spaces.\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 \bullet\tab
a blank line between items is ignored, for {\plain L{\up6\fs19 A}T{\dn7 E}X} is responsible for spacing items. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 \bullet\tab
{\plain L{\up6\fs19 A}T{\dn7 E}X} is in paragraph-setting mode when it reads the text of an item, and so will perform all the usual functions \par
}}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 Lists can also be embedded within one another, for they are just environments and we said that environments have this property. Remember that we must nest them in the correct order. We demonstrate with the following list, which also shows how to use the {\i0\scaps0\b0\f3 enumerate} environment.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\noindent I still have to do the following things:
\par \\begin\{enumerate\}
\par \\item Sort out LAN accounts for people on the course
\par   \\begin\{itemize\}
\par   \\item Have new accounts created for those not already
\par      registered on the LAN
\par   \\item Make sure all users have a personal directory
\par     on the data drive
\par   \\item Give read and scan rights to users in the \\TeX\\
\par      directories
\par   \\item Add users to the appropriate LAN print queues
\par   \\end\{itemize\}
\par \\item Have a \\TeX\\ batch file added to a directory that
\par   is on a public search path
\par \\item Finish typing these course notes and proof-read them
\par \\item Photocopy and bind the finished notes
\par \\end\{enumerate\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will give the following list\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19  I still have to do the following things: {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 1.\tab
Sort out LAN accounts for people on the course {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li1200\fi-300 \fs19 \bullet\tab
Have new accounts created for those not already registered on the LAN \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li1200\fi-300 \fs19 \bullet\tab
Make sure all users have a personal directory on the data drive \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li1200\fi-300 \fs19 \bullet\tab
Give read and scan rights to users in the {\plain T{\dn7 E}X} directories \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li1200\fi-300 \fs19 \bullet\tab
Add users to the appropriate LAN print queues \par
}\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 2.\tab
Have a {\plain T{\dn7 E}X} batch file added to a directory that is on a public search path \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 3.\tab
Finish typing these course notes and proof-read them \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 4.\tab
Photocopy and bind the finished notes \par
}}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 See how I lay the source file out in a readable fashion. This is to assist myself, not {\plain L{\up6\fs19 A}T{\dn7 E}X}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The {\i0\scaps0\b0\f3 description} environment is, unsurprisingly, for making lists of descriptions.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{description\}
\par \\item[\\tt itemize] an environment for setting itemised lists.
\par \\item[\\tt enumerate] an environment for setting numbered lists.
\par \\item[\\tt description] an environment for listing descriptions.
\par \\end\{description\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will typeset the following descriptions:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 {\b \i0\scaps0\b0\f3 itemize} an environment for setting itemised lists. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 {\b \i0\scaps0\b0\f3 enumerate} an environment for setting numbered lists. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 \fs19 {\b \i0\scaps0\b0\f3 description} an environment for listing descriptions. \par
}}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 Note that the scope of the {\b0\i0\scaps0\f3 \\tt} commands used in the item labels was restricted to the labels.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.21  {\i0\scaps0\b0\f3 tabbing} environment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 This environment simulates tabbing on typewriters. There one chose the tab stops in advance (analysing the material to be typed for the longest item in each column) and typed entries consecutively, hitting the tab key to move to the next tab stop and return to move to the next line.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 In the {\i0\scaps0\b0\f3 tabbing} environment, we proceed similarly. We look for the worst-case line (that which will determine the desired tab stops) and use it to set the tabs by inserting {\b0\i0\scaps0\f3 \\=} control symbols at the points where we want tab stops. We then discard that line using {\b0\i0\scaps0\f3 \\kill}, since the worst-case line might not be the first line in the material we have to type. We then type each line, using {\b0\i0\scaps0\f3 \\>} to move to the next tab stop and {\b0\i0\scaps0\f3 \\\\} to end a line.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{tabbing\}
\par Cheddar cheese \\= Recommended \\= \\$2.00 \\kill
\par Green Ham \\> Recommended \\> \\$2.00
\par Eggs \\> 1 a week \\> \\$1.50
\par Cheddar cheese \\> Hmmm \\> \\$0.80
\par Yak cheese \\> Avoid \\> \\$0.05
\par \\end\{tabbing\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 gives the following uniformly-tabbed table\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {\par
{\trowd\cellx3073\cellx6146\cellx9219
{\pard\intbl\ql Green Ham\cell}
{\pard\intbl\ql Recommended\cell}
{\pard\intbl\ql $2.00\cell}
\row}
{\trowd\cellx3073\cellx6146\cellx9219
{\pard\intbl\ql Eggs\cell}
{\pard\intbl\ql 1 a week\cell}
{\pard\intbl\ql $1.50\cell}
\row}
{\trowd\cellx3073\cellx6146\cellx9219
{\pard\intbl\ql Cheddar cheese\cell}
{\pard\intbl\ql Hmmm\cell}
{\pard\intbl\ql $0.80\cell}
\row}
{\trowd\cellx3073\cellx6146\cellx9219
{\pard\intbl\ql Yak cheese\cell}
{\pard\intbl\ql Avoid\cell}
{\pard\intbl\ql $0.05\cell}
\row}
} }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 In the format line I chose the longest entry from each of the prospective columns. I lined some of the {\b0\i0\scaps0\f3 \\>} commands up in the source just to keep things readable.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Remember that excess spaces are ignored. {\plain L{\up6\fs19 A}T{\dn7 E}X} sets the {\b0\i0\scaps0\f3 \\kill}ed line normally and sees where the tab stops requested will be needed in the typeset text. Note also that commands given within the {\i0\scaps0\b0\f3 tabbing} environment are local to {\i the current item}. \par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Actually, we use the above approach in the case that we require uniformly tabbed columns. The format line is not compulsory, and we can define tab stops dynamically. See if you can make sense of the following.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{tabbing\}
\par Entry in position 1,1 \\= Entry 1,2 \\= Entry 1,3\\\\
\par Entry in position 2,1 \\> Entry 2,2 \\> Entry 2,3\\\\
\par Entry 3,1 \\= Entry 3,2 \\> Entry 3,3\\\\
\par Entry 4,1 \\> Entry 4,2 \\> Entry 4,3
\par \\end\{tabbing\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which produces\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {\par
{\trowd\cellx3073\cellx6146\cellx9219
{\pard\intbl\ql Entry in position 1,1\cell}
{\pard\intbl\ql Entry 1,2\cell}
{\pard\intbl\ql Entry 1,3\cell}
\row}
{\trowd\cellx3073\cellx6146\cellx9219
{\pard\intbl\ql Entry in position 2,1\cell}
{\pard\intbl\ql Entry 2,2\cell}
{\pard\intbl\ql Entry 2,3\cell}
\row}
{\trowd\cellx3073\cellx6146\cellx9219
{\pard\intbl\ql Entry 3,1\cell}
{\pard\intbl\ql Entry 3,2\cell}
{\pard\intbl\ql Entry 3,3\cell}
\row}
{\trowd\cellx3073\cellx6146\cellx9219
{\pard\intbl\ql Entry 4,1\cell}
{\pard\intbl\ql Entry 4,2\cell}
{\pard\intbl\ql Entry 4,3\cell}
\row}
} }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 The are additional commands that can be used within the tabbing environment to achieve special effects, but we won\rquote t be discussing them here.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.22  {\i0\scaps0\b0\f3 tabular} environment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 The {\i0\scaps0\b0\f3 tabular} environment is used to produce tables of items, particularly when the table is predominantly rectangular and when line drawing is required. {\plain L{\up6\fs19 A}T{\dn7 E}X} will make most decisions for us; for instance it will align everything for us without having to be told which are the longest entries in each column.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 This environment is the first of many that use the {\plain T{\dn7 E}X} \ldblquote tabbing character\rdblquote  {\i0\scaps0\b0\f3 &}. This character is used to separate consecutive entries in a row of a table, array, etc. The end of a row is indicated in the usual manner, by using {\b0\i0\scaps0\f3 \\\\}. In this way the individual cells of the table, or array, are clearly described to {\plain L{\up6\fs19 A}T{\dn7 E}X}, and it can analyse them to make typesetting decisions. Commands issued within a cell so defined are, again, local to that cell.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The {\i0\scaps0\b0\f3 tabular} environment is also our first example of an {\i environment with arguments}. The arguments are given, in braces as usual, just after the closing brace after the environments name. In the case of {\i0\scaps0\b0\f3 tabular} there is a single mandatory argument giving the justification of the entries in each column: {\i0\scaps0\b0\f3 l} for left justified, {\i0\scaps0\b0\f3 r} for right justified, and {\i0\scaps0\b0\f3 c} for centred. There must be an entry for each column of the table, and there is no default. Let\rquote s start with a simple table.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{tabular\}\{llrrl\}
\par \\bf Student name & \\bf Number & \\bf Test 1 & \\bf Test 2 & \\bf Comment\\\\
\par F. Basset    & 865432 & 78     & 85     & Pleasing\\\\
\par H. Hosepipe  & 829134 & 5      & 10     & Improving\\\\
\par I.N. Middle  & 853931 & 48     & 47     & Can make it
\par \\end\{tabular\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will produce the following no-frills table\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {\par
{\trowd\cellx2547\cellx4176\cellx5805\cellx7434\cellx9216
{\pard\intbl\ql {\i0\scaps0\b Student name}\cell}
{\pard\intbl\ql {\i0\scaps0\b Number}\cell}
{\pard\intbl\qr {\i0\scaps0\b Test 1}\cell}
{\pard\intbl\qr {\i0\scaps0\b Test 2}\cell}
{\pard\intbl\ql {\i0\scaps0\b Comment}\cell}
\row}
{\trowd\cellx2547\cellx4176\cellx5805\cellx7434\cellx9216
{\pard\intbl\ql {F. Basset}\cell}
{\pard\intbl\ql {865432}\cell}
{\pard\intbl\qr {78}\cell}
{\pard\intbl\qr {85}\cell}
{\pard\intbl\ql {Pleasing}\cell}
\row}
{\trowd\cellx2547\cellx4176\cellx5805\cellx7434\cellx9216
{\pard\intbl\ql {H. Hosepipe}\cell}
{\pard\intbl\ql {829134}\cell}
{\pard\intbl\qr {5}\cell}
{\pard\intbl\qr {10}\cell}
{\pard\intbl\ql {Improving}\cell}
\row}
{\trowd\cellx2547\cellx4176\cellx5805\cellx7434\cellx9216
{\pard\intbl\ql {I.N. Middle}\cell}
{\pard\intbl\ql {853931}\cell}
{\pard\intbl\qr {48}\cell}
{\pard\intbl\qr {47}\cell}
{\pard\intbl\ql {Can make it}\cell}
\row}
} }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Note that a {\b0\i0\scaps0\f3 \\\\} was not necessary at the end of the last row. Also note that, once again, the alignment of the {\b0\i0\scaps0\f3 &} characters was for human readability. It is conventional to set columns of numbers with right justification. The {\b0\i0\scaps0\f3 \\bf} directives apply only the entries in which they are given.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 A {\i0\scaps0\b0\f3 \emdash } typed in the {\i0\scaps0\b0\f3 tabular} environment\rquote s argument causes a vertical line to be drawn at the indicated position and extending for the height of the entire table. An {\b0\i0\scaps0\f3 \\hline} given in the environment draws a horizontal line extending the width of the table to be drawn at the vertical position at which the command is given. A {\b0\i0\scaps0\f3 \\cline}{\{{\i i}}-{{\i j}\}} draws a line spanning columns {{\i i}} to {{\i j}}, at the vertical position at which the command is given. A repeated line-drawing command causes a double line to be drawn. We illustrate line drawing in tables by putting some lines into our first table. We will type this example in a somewhat expanded form, trying to make it clear why the lines appear where they do.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{tabular\}\{|l|l|r|r|l|\}
\par \\hline
\par \\bf Student name & \\bf Number & \\bf Test 1 & \\bf Test 2 & \\bf Comment\\\\
\par \\hline
\par F. Basset        & 865432     & 78         & 85         & Pleasing\\\\
\par \\hline
\par H. Hosepipe      & 829134     & 5          & 10         & Improving\\\\
\par \\hline
\par I.N. Middle      & 853931     & 48         & 47         & Can make it\\\\
\par \\hline
\par \\end\{tabular\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which will give\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {\par
{\trowd\clbrdrl\brdrs\clbrdrt\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx3233\clbrdrl\brdrs\clbrdrt\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx4695\clbrdrl\brdrs\clbrdrt\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6157\clbrdrl\brdrs\clbrdrt\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7619\clbrdrl\brdrs\clbrdrt\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { \i0\scaps0\b Student name}\cell}
{\pard\intbl\ql {\i0\scaps0\b Number}\cell}
{\pard\intbl\qr {\i0\scaps0\b Test 1}\cell}
{\pard\intbl\qr {\i0\scaps0\b Test 2}\cell}
{\pard\intbl\ql {\i0\scaps0\b Comment}\cell}
\row}
{\trowd\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx3233\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx4695\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6157\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7619\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { F. Basset}\cell}
{\pard\intbl\ql {865432}\cell}
{\pard\intbl\qr {78}\cell}
{\pard\intbl\qr {85}\cell}
{\pard\intbl\ql {Pleasing}\cell}
\row}
{\trowd\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx3233\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx4695\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6157\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7619\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { H. Hosepipe}\cell}
{\pard\intbl\ql {829134}\cell}
{\pard\intbl\qr {5}\cell}
{\pard\intbl\qr {10}\cell}
{\pard\intbl\ql {Improving}\cell}
\row}
{\trowd\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx3233\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx4695\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6157\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx7619\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9217
{\pard\intbl\ql { I.N. Middle}\cell}
{\pard\intbl\ql {853931}\cell}
{\pard\intbl\qr {48}\cell}
{\pard\intbl\qr {47}\cell}
{\pard\intbl\ql {Can make it}\cell}
\row}
} }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 That way of laying out the source file makes it clear where the lines will go. As we (by now) well know, the returns that we pressed after the {\b0\i0\scaps0\f3 \\\\}s in typing this table might as well have been spaces as far as {\plain L{\up6\fs19 A}T{\dn7 E}X} is concerned. Thus it is common to have the {\b0\i0\scaps0\f3 \\hline} commands following the {\b0\i0\scaps0\f3 \\\\}s on the input lines. We will do this in future examples.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The {\b0\i0\scaps0\f3 \\multicolumn} column can be used to overrule the overall format of the table for a few columns. The syntax of this command is\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\i0\scaps0\b0\f3 \pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 \f3 \u92?multicolumn \{{\i n}\}\{{\i pos}\}\{{\i item}\} \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 where {{\i n}} is the number of columns of the original format that {\i item} is to span, and {\i pos} specifies the justification of the new argument.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{tabular\}\{||l|c|c|c||\} \\hline
\par \\multicolumn\{4\}\{|c|\}\{\\LaTeX\\ size changing commands\}\\\\ \\hline
\par Style option         & 10pt (default) & \\tt 11pt & \\tt 12pt\\\\ \\hline
\par \\tt\\bs footnotesize  & 8pt            & 9pt      & 10pt\\\\ \\hline
\par \\tt\\bs small         & 9pt            & 10pt     & 11pt\\\\ \\hline
\par \\tt\\bs large         & 12pt           & 12pt     & 14pt\\\\ \\hline
\par \\end\{tabular\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 produces the following table:\par
{\fs19 {\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 \par
{\trowd\clmgf\clbrdrl\brdrs\clbrdrt\brdrs\clbrdrb\brdrs\cellx4720\clmrg\clbrdrt\brdrs\clbrdrb\brdrs\cellx6780\clmrg\clbrdrt\brdrs\clbrdrb\brdrs\cellx8000\clmrg\clbrdrt\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx9220
{\pard\intbl\qc { {\plain L{\up6\fs19 A}T{\dn7 E}X} size changing commands\cell}
{\pard\intbl\cell}
{\pard\intbl\cell}
{\pard\intbl}\cell}
\row}
{\trowd\clbrdrl\brdrdb\clbrdrb\brdrs\clbrdrr\brdrs\cellx4720\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6780\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx8000\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrdb\cellx9220
{\pard\intbl\ql { Style option}\cell}
{\pard\intbl\qc {10pt (default)}\cell}
{\pard\intbl\qc {\i0\scaps0\b0\f3 11pt}\cell}
{\pard\intbl\qc {\i0\scaps0\b0\f3 12pt}\cell}
\row}
{\trowd\clbrdrl\brdrdb\clbrdrb\brdrs\clbrdrr\brdrs\cellx4720\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6780\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx8000\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrdb\cellx9220
{\pard\intbl\ql { \i0\scaps0\b0\f3 \u92?footnotesize}\cell}
{\pard\intbl\qc {8pt}\cell}
{\pard\intbl\qc {9pt}\cell}
{\pard\intbl\qc {10pt}\cell}
\row}
{\trowd\clbrdrl\brdrdb\clbrdrb\brdrs\clbrdrr\brdrs\cellx4720\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6780\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx8000\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrdb\cellx9220
{\pard\intbl\ql { \i0\scaps0\b0\f3 \u92?small}\cell}
{\pard\intbl\qc {9pt}\cell}
{\pard\intbl\qc {10pt}\cell}
{\pard\intbl\qc {11pt}\cell}
\row}
{\trowd\clbrdrl\brdrdb\clbrdrb\brdrs\clbrdrr\brdrs\cellx4720\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx6780\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrs\cellx8000\clbrdrl\brdrs\clbrdrb\brdrs\clbrdrr\brdrdb\cellx9220
{\pard\intbl\ql { \i0\scaps0\b0\f3 \u92?large}\cell}
{\pard\intbl\qc {12pt}\cell}
{\pard\intbl\qc {12pt}\cell}
{\pard\intbl\qc {14pt}\cell}
\row}
} \par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.23  {\i0\scaps0\b0\f3 figure} and {\i0\scaps0\b0\f3 table} environments\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Figures (diagrams, pictures, etc.) and tables (perhaps created with the {\i0\scaps0\b0\f3 tabular} environment) cannot be split across pages. So {\plain L{\up6\fs19 A}T{\dn7 E}X} provides a mechanism for \ldblquote floating\rdblquote  them to a nearby place where there is room for them. This may mean that your figure or table may appear a little later in the document than its declaration in the source file might suggest. You can suggest to {\plain L{\up6\fs19 A}T{\dn7 E}X} that it try to place the figure or table at the present position if there is room or, failing that, at the top or bottom of the present or following page. You can also ask for it to be presented by itself on a \ldblquote page of floats\rdblquote . \par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 You suggest these options to {\plain L{\up6\fs19 A}T{\dn7 E}X} through an optional argument to the environment. One lists a combination of the letters {\i0\scaps0\b0\f3 h}, {\i0\scaps0\b0\f3 t}, {\i0\scaps0\b0\f3 b}, and {\i0\scaps0\b0\f3 p} where {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\b h} means that the object should be placed {\i here} if there is room, so that things will appear in the same order as in the source file, \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\b t} means that the object can be placed at the {\i top} of the of a text page, but no earlier than the present page. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\b b} means that the object can be placed at the {\i bottom} of a text page, but no earlier than the present page. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 {\b p} means that the object should be set on a {\i page of floats} that consists only of tables and figures. \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 A combination of these indicates decreasing order of preference. The default is {\i0\scaps0\b0\f3 tbp}. In this document I have tended to use {\i0\scaps0\b0\f3 htbp}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\plain L{\up6\fs19 A}T{\dn7 E}X} will also number and caption a figure or table for you, and compile a list of tables and a list of figures. Just include {\b0\i0\scaps0\f3 \\listoffigures} and {\b0\i0\scaps0\f3 \\listoftables} next to your {\b0\i0\scaps0\f3 \\tableofcontents} command at the beginning of the document. To caption a table of figure, include {\b0\i0\scaps0\f3 \\caption\{}{\i caption text}{\b0\i0\scaps0\f3 \}} just before the {\b0\i0\scaps0\f3 \\end\{table\}} or {\b0\i0\scaps0\f3 \\end\{figure\}} command. Here\rquote s a sample source file.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{table\}[htbp]
\par   \\begin\{tabular\}\{lrll\}
\par   ...
\par   \\end\{tabular\}
\par \\caption\{Mark analysis\}
\par \\end\{table\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 To leave space for a figure that will inserted by some other means at a later date, we can use the {\b0\i0\scaps0\f3 \\vspace} command:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{figure\}[htbp]
\par \\vspace\{9.5cm\}
\par \\caption\{An artists impression\}
\par \\end\{figure\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Including graphics files prepared with drawing packages is possible, but beyond the scope of this introduction.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 2.4.24  The {\i0\scaps0\b0\f3 letter} document style\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 All this and we still don\rquote t know how to prepare a simple letter! Actually, there is very little to it.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Figure\~{\field{\*\fldinst{\lang1024 REF BMfig_letter \\* MERGEFORMAT }}{\fldrslt{2.1}}} shows a sample letter. We declare our own address and signature before entering the {\i0\scaps0\b0\f3 letter} environment because we can use repeated {\i0\scaps0\b0\f3 letter} environments to prepare multiple letters from the same source file. The address of the intended recipient of a particular letter is given as an argument to the {\i0\scaps0\b0\f3 letter} environment.\par
{\pard\plain\s31\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi360  {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\documentstyle[12pt]\{letter\}
\par \\begin\{document\}
\par \\address\{(Underneath) Lion Bridge\\\\
\par Midway down Commercial Road\\\\
\par Pietermaritzburg\\\\
\par 3200\}
\par 
\par \\signature\{F. Basset\\\\
\par Public nuisance\}
\par 
\par \\begin\{Letter\}\{Director of Public Parks\\\\
\par Pietermaritzburg Municipality\\\\
\par Pietermaritzburg\}
\par 
\par \\opening\{Kind Sir/Madam\}
\par 
\par I wish to complain about the shocking practice of
\par fencing off the base of trees.  I notice with grave
\par concern that this has occurred in the park bordering
\par my stately residence.
\par 
\par This has already caused me great inconvenience
\par and public embarrassment, as you can imagine it would
\par for a hound of my social standing.  I demand that
\par you take these obscene obstructions away without
\par delay.
\par 
\par \\closing\{Yours anxiously\}
\par \\end\{letter\}
\par \\end\{document\}
\par \par
}}\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 {Figure {\*\bkmkstart BMfig_letter}2.1{\*\bkmkend BMfig_letter}: A sample letter}{\field{\*\fldinst TC "2.1 A sample letter" \\f f}{\fldrslt }}\par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 2.4.25  Common pitfalls; Error messages\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 By now it should be clear that we have to work quite accurately when preparing a document. Typing errors in the running text can be absorbed, but messing up a control sequence name will halt the compiler with an error message. Before we look at some common errors and some ways to avoid them, let\rquote s have a look at a sample error message.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 You\rquote ll have noticed by now that when you run {\plain L{\up6\fs19 A}T{\dn7 E}X} on a source file, the transcript of the compiler session is written on a log file. When errors have accumulated to the point that {\plain L{\up6\fs19 A}T{\dn7 E}X} is hopelessly confused, it is time to debug your source file. The log file contains a reference to the line, or lines, of your source file that generated the error together with a description of the error.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\plain T{\dn7 E}X} and {\plain L{\up6\fs19 A}T{\dn7 E}X} error messages appear frightening at first sight, to say the least. They are actually very informative, but they can take some getting used to. Mistyped control sequences cause little pain, but a missing {\b0\i0\scaps0\f3 \\end\{}{\i environment}{\b0\i0\scaps0\f3 \}} can cause a good deal of confusion because it has the effect of making {\plain L{\up6\fs19 A}T{\dn7 E}X} try to set material into that environment that was never intended/designed to fit in such a place. Also, ommiting a mandatory argument can cause great confusion.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Suppose we type {\b0\i0\scaps0\f3 \\bold} instead of {\b0\i0\scaps0\f3 \\bf} in the following line:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par this is going to be \{\\bold very\} messy.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 This produces the following error message:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par ! Undefined control sequence.
\par 1.683 this is going to be \{\\bold
\par        very\} messy.
\par ?
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 That not so bad! The line beginning with {\i0\scaps0\b0\f3 !} tells us that we have tried to used a control sequence that was not known to {\plain L{\up6\fs19 A}T{\dn7 E}X}; the {\i0\scaps0\b0\f3 1.683} tells us that the error occurred on line 683 of the source file; and the error message is split over two lines with the break occurring at the point where {\plain L{\up6\fs19 A}T{\dn7 E}X} detected a problem.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 But suppose we try the following\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{tabular\}\{llrrl\}
\par Student name & Number & Test 1 & Test 2 & Comment\\\\
\par F. Basset    & 865432 & 78     & 85     & Pleasing\\\\
\par H. Hosepipe  & 829134 & 5      & 10     & Improving\\\\
\par I.N. Middle  & 853931 & 48     & 47     & Can make it
\par 
\par This shows that H.~Hosepipe's newfound concentration has...
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 i.e., we omit to provide the {\b0\i0\scaps0\f3 \\end\{tabular\}} that delimits the end of the environment. Not having been told that the environment is supposed to be concluded, {\plain L{\up6\fs19 A}T{\dn7 E}X} will try to set the text of the next paragraph as a table item\emdash and will scream blue murder when it finds that it doesn\rquote t conform to the syntax demanded.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par LaTeX error.  See LaTeX manual for explanation.
\par    Type  H <return>  for immediate help.
\par ! \\begin\{tabular\} ended by \\end\{document\}.
\par \\@latexerr ...diate help.\}\\errmessage \{#1\}
\par 
\par \\@checkend ...urrenvir \\else \\@badend \{#1\}
\par           \\fi 
\par \\enddocument ->\\@checkend \{document\}
\par            \\clearpage \\begingroup \\if@filesw...
\par \\end #1->\\csname end#1\\endcsname 
\par         \\@checkend \{#1\}\\expandafter \\endgrou...
\par l.58 \\end\{document\}
\par 
\par ? 
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Now {\i that\rquote s} informative! Actually it {\i is} if we agree to ignore all but the the error indication line (the one beginning with the {\i0\scaps0\b0\f3 !}) and the line telling us where {\plain L{\up6\fs19 A}T{\dn7 E}X} noticed that all was not well (the one beginning {\i0\scaps0\b0\f3 1.58} in this case). The rest of the error message you can regard as being for your local {\plain T{\dn7 E}X} wizard to sort your problem out if you are unable to after consulting the manuals. Tough as it looks, we can decipher this message straight away: the error indicator line tell us that a {\i0\scaps0\b0\f3 tabular} environment was ended incorrectly (in this case by an {\b0\i0\scaps0\f3 \\end\{document\}}).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\plain T{\dn7 E}X} error messages aren\rquote t all that bad once you\rquote ve made enough errors to get used to a few! Most can be avoided through {\i careful} preparation of the source file. Typing accurately and knowledge of the command syntax is a good start, but there are some other precautions that make good sense: {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 1.\tab
Even if {\plain L{\up6\fs19 A}T{\dn7 E}X} is happy with free-form input, try to lay your input file out as regularly and logically as possible. See our examples of environments for formats to adopt. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 2.\tab
It is important that all group delimiters be properly matched, i.e., braces and {\i0\scaps0\b0\f3 \u92?begin\{\}}\u8230?{\i0\scaps0\b0\f3 \u92?end\{\}} must come in pairs. A good habit to fall in to is to always type such things in pairs and then move the cursor back between them and type the intervening material. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 3.\tab
Don\rquote t forget command arguments when they are mandatory. Always ask yourself what a particular commands {\i needs from you} in order to make the decisions that are required of it. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 4.\tab
Remember the 10 characters that are specially reserved for commenting, table item separation, etc. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 5.\tab
When we look at mathematical typesetting in the next chapter, we will see that the same principles apply there. \par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 6.\tab
Try to use a text editor that has a {\plain T{\dn7 E}X} mode, or at least one that will match brackets for you. \par
}\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb300 \fi0 2.5  Summary\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We have learned pretty much all we need to know in order to prepare non-mathematical documents. There has been quite a lot of material, all told, but we\rquote re fortunate that the average document requires only a fraction of what we\rquote ve listed here. Furthermore, we\rquote ll find that what we\rquote ve learned equips us with a good deal of the framework needed for mathematical typesetting.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The important thing to extract from this chapter is some feel for what I termed the \ldblquote spirit of {\plain T{\dn7 E}X}\rdblquote  at the chapter beginning. I cannot emphasise enough the importance of getting your mind out of \ldblquote word processing\rdblquote  mode and into \ldblquote typesetting\rdblquote  mode. Always keep uppermost in your mind the task at hand: you are to describe the logical content of the document to {\plain L{\up6\fs19 A}T{\dn7 E}X}, so furnishing it with enough information to perform all the formatting for you.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Many of the earlier sections of this chapter will become trivially easy to you after just a little experimentation with {\plain L{\up6\fs19 A}T{\dn7 E}X}. The best way to learn the syntax of the more complicated environments is to use them\emdash try typesetting the examples, for instance. It is important that you come to terms with the {\i0\scaps0\b0\f3 tabular} environment, for its syntax is typical of many of the mathematical constructs that we will use.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 If you have not already done so, then now is the time to try preparing some documents of your own. Try including all the material from this chapter, for that is the best way to remember it all. When the initial lack of familiarity wears off, you\rquote ll find that {\plain L{\up6\fs19 A}T{\dn7 E}X} is really a whole lot friendlier and easier to use than you expected.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We must also recognise that there is a lot more to some of the command than detailed here. Some accept optional argumnets that were not mentioned, others have more options than we considered. And even once we have a full description of each command, there is still much to be learned for there is much that can be achieved through creative use of some of the environments.\par
\page
\pard\plain\ql\sb240\sa120\keepn\f0\b\fs40\sl240\slmult1 \fi0 Chapter 3\par
\pard\plain\s2\ql\sb240\sa120\keepn\f0\b\fs40\sl240\slmult1 \sb240 \fi0 Mathematical typesetting with {\plain L{\up6\fs19 A}T{\dn7 E}X}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0 The last chapter taught us a good deal of what we need to know in order to prepare quite complicated non-mathematical documents. There are still a number of useful topics that we have not covered (such as cross-referencing), but we\rquote ll defer discussion of those until a later chapter. In the present chapter, we\rquote ll learn how {\plain L{\up6\fs19 A}T{\dn7 E}X} typesets mathematics. It should come as no surprise that {\plain L{\up6\fs19 A}T{\dn7 E}X} does most of the work for us.\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 3.1  Introduction\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 In text-only documents we saw that our task was to describe the logical components of each sentence, paragraph, section, table, etc. When we tell {\plain L{\up6\fs19 A}T{\dn7 E}X} to go into {\i mathematical mode}, we have to describe the logical parts of a formula, matrix, operator, special symbol, etc. {\plain T{\dn7 E}X} has been taught to recognize a binary operation, a binary relation, a variable, an operator that expects limits, and so on. We just need to supply the parts that make up each of these, and {\plain T{\dn7 E}X} will take care of the rest. It will leave appropriate space around operators, italicise variables, set an operator name in roman type, leave the correct space after colons, place sub- and superscripts in the correct positions (based on what it is you\rquote re working with), choose the correct typesizes, \u8230? the list of things it has been taught is enormous. When you want to revert to setting normal text again, you tell {\plain L{\up6\fs19 A}T{\dn7 E}X} too leave maths mode and go back into the mode it was in (paragraphing mode).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\plain L{\up6\fs19 A}T{\dn7 E}X} cannot be expected to perform these mode shifts itself, for it is not always clear just when it is mathematics that has been typed. For example, should an isolated letter {\i0\scaps0\b0\f3 a} in the input file be regarded as a word (as in the definite article) or a mathematical variable (as in the variable {{\i a}}). There are no reliable rules for {\plain L{\up6\fs19 A}T{\dn7 E}X} to make such decisions by, so the begin-math and end-math mode switching is left entirely to you.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The symbol {\b0\i0\scaps0\f3 $} is specially reserved{\cs62\super\chftn}
{\*\footnote\pard \s65\ql\fi-113\li397\lin397\f0\fs24{\cs62\super\chftn} See section {\field{\*\fldinst{\lang1024 REF BMsec_reserved \\* MERGEFORMAT }}{\fldrslt{2.4.4}}}}
 by {\plain L{\up6\fs19 A}T{\dn7 E}X} as the \ldblquote math shift\rdblquote  symbol. When {\plain L{\up6\fs19 A}T{\dn7 E}X} starts setting a document it is in paragraphing mode, ready to set lines of the input file into paragraphs. It remains in this mode until it encounters a {\b0\i0\scaps0\f3 $} symbol, which shifts {\plain L{\up6\fs19 A}T{\dn7 E}X} into mathematical mode. It now knows to be on the look-out for the components of a mathematical expression, rather than for words and paragraphs. It reads everything up to the next {\b0\i0\scaps0\f3 $} sign in this mathemtical mode, and then shifts back to paragraphing mode (i.e. the mode it was in before we took it in to maths mode).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 You must be careful to balance your begin-math and end-math symbols. It is often a good idea to type two {\b0\i0\scaps0\f3 $} symbols and then move back between them and type the mathematical expression. If the math-shift symbols in a document are not matched, then {\plain L{\up6\fs19 A}T{\dn7 E}X} will become confused because it will be trying to set non-mathematical material as mathematics.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 For those who find having the same symbol for both math-begin and math-end confusing or dangerous, there are two control symbols that perform the same operations: the control symbol {\b0\i0\scaps0\f3 \\(} is a begin-math instruction, and the control symbol {\b0\i0\scaps0\f3 \\)} is an end-math instruction. Since it is easy to \ldblquote lose\rdblquote  a {\b0\i0\scaps0\f3 $} sign when typing a long formula, a math environment is provided for such occasions: you can use {\b0\i0\scaps0\f3 \\begin\{math\}} and {\b0\i0\scaps0\f3 \\end\{math\}} as the math-shift instructions. Of course, you could just decide to use {\b0\i0\scaps0\f3 $} and take your chances.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Let\rquote s have a look at some mathematics.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\LaTeX\\ is normally in paragraphing mode, where
\par it expects to find the usual paragraph material.  Including
\par a mathematical expression, like $2x+3y - 4z= -1$, in the
\par paragraph text is easy.  \\TeX\\ has been taught to recognize
\par the basic elements of an expression, and typeset them appropriately,
\par choosing spacing, positioning, fonts, and so on.
\par Typing the above expression without entering maths
\par mode produces the incorrect result: 2x+3y - 4z= -1
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will produce the following paragraph\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19  {\plain L{\up6\fs19 A}T{\dn7 E}X} is normally in paragraphing mode, where it expects to find the usual paragraph material. Including a mathematical expression, like {2{\i x}+3{\i y}\u8722?4{\i z}=\u8722?1}, in the paragraph text is easy. {\plain T{\dn7 E}X} has been taught to recognize the basic elements of an expression, and typeset them appropriately, choosing spacing, positioning, fonts, and so on. Typing the above expression without entering maths mode produces the incorrect result: 2x+3y - 4z= -1 }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Notice that {\plain L{\up6\fs19 A}T{\dn7 E}X} sets space around the binary relation {=} and space around the binary operators {+} and {\u8722?} on the left hand side of the equation, ignoring the spacing we typed in the input. It was also able to recognize that the {\u8722?1} on the right hand side of the equation was a unary minus\emdash negating the {1} rather than being used to indicate subtraction\emdash and so did not put space around it. It also italicised the variables {{\i x}}, {{\i y}}, and {{\i z}}. However, it did not italicise the number {1}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 In typing a mathematical expression we must remember to keep the following in mind: {\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 1.\tab
All letters that are not part of an argument to some control sequence will be italicised. Arguments to control sequences will be set according to the definition of the command used. So typing {\b0\i0\scaps0\f3 $f(x)>0 for x > 1$} will produce \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \li600\fi0 \tab
{\i f}({\i x})>0{\i f}{\i o}{\i r}{\i x}>1\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li600\fi0 instead of the expression \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \li600\fi0 \tab
{\i f}({\i x})>0{{    }for{    }}{\i x}>1\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li600\fi0 that we intended. Numerals and punctuation marks are set in normal roman type but {\plain L{\up6\fs19 A}T{\dn7 E}X} will take care of the spacing around punctuation symbols, as in\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \li600\fi0 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \li600\fi0 \fs19 
\par $f(x,y) \\geq 0$
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \li600\fi0 which produces \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \li600\fi0 \tab
{\i f}({\i x},{\i y}){\u8805*}0{    }.\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 2.\tab
Even a single letter can constitute a formula, as in \ldblquote the constant {{\i a}}\rdblquote . To type this you enter {\b0\i0\scaps0\f3 $a$} in your source file. If you do not go in to maths mode to type the symbol, you\rquote ll get things like \ldblquote the constant a\rdblquote .\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 3.\tab
Some symbols have a different meaning when typed in maths mode. Not only do ordinary letters become variables, but symbols such as {\b0\i0\scaps0\f3 -} and {\b0\i0\scaps0\f3 +} are now interpreted as mathematical symbols. Thus in maths mode {\b0\i0\scaps0\f3 -} is no longer considered a hyphen, but as a minus sign.\par
\pard\plain\s46\ql\fi-283\li283\lin283\sb0\sa120\widctlpar\tql\tx283\f0\fs24\sl240\slmult1 \sb50 \li600\fi-300 4.\tab
{\plain L{\up6\fs19 A}T{\dn7 E}X} ignores all spaces and carriage returns when in maths mode, without exception. So typing something like {\b0\i0\scaps0\f3 the constant$ a$} will produce \ldblquote the constant{{\i a}}\rdblquote . You should have typed {\b0\i0\scaps0\f3 the constant $a$}. {\plain L{\up6\fs19 A}T{\dn7 E}X} is responsible for all spacing when in maths mode, and (as in paragraphing mode) you have to specially ask to have spacing changed. Even if {\plain L{\up6\fs19 A}T{\dn7 E}X} does ignore all spaces when in maths mode you should (as always in {\plain T{\dn7 E}X}) still employ spaces to keep your source file readable. \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 The above means that, at least for most material, a typist need not understand the mathematics in order to typeset it correctly. And even if one does understand the mathematics, {\plain L{\up6\fs19 A}T{\dn7 E}X} is there to make sure that you adhere to accepted typesetting conventions (whether you were aware of their existence or not).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 So one could type either\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par $f(x, y)  =  2 (x+ y)y/(5xy - 3  )$
\par \par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 \fs19 {\fs24 or}\par
{\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par $f(x,y) = 2(x+y)y / (5xy-3)$
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 and you\rquote d still get the correct result \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\i f}({\i x},{\i y})=2({\i x}+{\i y}){\i y}/(5{\i x}{\i y}\u8722?3){    }.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 There are some places where this can go wrong. For instance, if we wish to speak of the {{\i x}}-{{\i y}} plane then one has to know that it is an {\i endash} that is supposed to be placed between the {{\i x}} and the {{\i y}}, not a minus sign (as {\b0\i0\scaps0\f3 $x-y$} would produce). But typing {\b0\i0\scaps0\f3 $x--y$} will produce {{\i x}\u8722?\u8722?{\i y}} since both dashes are interpreted as minus signs. To avoid speaking of the {{\i x}\u8722?{\i y}} plane or the {{\i x}\u8722?\u8722?{\i y}} plane, we should type it as {\b0\i0\scaps0\f3 the $x$--$y$ plane}. We are fortunate that {\plain L{\up6\fs19 A}T{\dn7 E}X} can recognise and cope with by far the majority of our mathematical typesetting needs.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Another thing to look out for is the use of braces in an expression. Typing\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par $\{x : f(x)>0\}$
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will not produce any braces. This is because, as we well know, braces are reserved for delimiting groups in the input file. Looking back to section\~{\field{\*\fldinst{\lang1024 REF BMsec_reserved \\* MERGEFORMAT }}{\fldrslt{2.4.4}}}, we see how it should be done:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par $ \\\{ x: f(x)>0 \\\} $
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Math shift commands also behave as scope delimiters, so that commands issued in an expression cannot affect anything else in a document.\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 {\*\bkmkstart BMsec_display}3.2{\*\bkmkend BMsec_display}  Displaying a formula\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} considers an expression {\b0\i0\scaps0\f3 $ ... $} to be word-like in the sense that it considers it to be eligible for splitting across lines of a paragraph (but without hyphenation, of course). {\plain L{\up6\fs19 A}T{\dn7 E}X} assigns quite a high penalty to doing this, thus trying to avoid it (remember that {\plain L{\up6\fs19 A}T{\dn7 E}X} tries to minimize the \ldblquote badness\rdblquote  of a paragraph). When there is no other way, it will split the expression at a suitable place. But there are some expressions which are just too long to fit into the running text without looking awkward. These are best \ldblquote displayed\rdblquote  on a line by themselves. Also, some expressions are sufficiently important that they should be made to stand out. These, too, should be displayed on a line of their own.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 The mechanism for displaying an expression is the {\i display math} mode, which is begun by typing {\b0\i0\scaps0\f3 $$} and ended by typing the same sequence (which again means that we\rquote d better be sure to type them in pairs). Corresponding to the alternatives {\b0\i0\scaps0\f3 \\(} and {\b0\i0\scaps0\f3 \\)} that we had for the math shift character {\b0\i0\scaps0\f3 $}, we may use {\b0\i0\scaps0\f3 \\[} and {\b0\i0\scaps0\f3 \\]} as the display-math shift sequences. One can also use the environment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{displaymath\} ... \\end\{displaymath\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which is equivalent to {\b0\i0\scaps0\f3 $$ ... $$} and is suitable for use with long displayed expressions. If you wish {\plain L{\up6\fs19 A}T{\dn7 E}X} to number your equations for you you can use the environment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{equation\} ... \\end\{equation\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which is the same as the {\b0\i0\scaps0\f3 displaymath} environment, except that an equation number will be generated.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 It is poor style to have a displayed expression either begin a paragraph or be a paragraph by itself. This can be avoided if you agree to {\i never leave a blank line in your input file before a math display}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We will see later how to typeset an expression that is to span multiple lines. For now, let\rquote s look at an example of displaying an expression:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par For each $a$ for which the Lebesgue-set $L_a(f) \\neq \\emptyset$ we define
\par $$ % We could have used \\begin\{displaymath\} here
\par \{\\cal B\}_a(f) = \\\{ L_\{a+r\}(f) : r > 0  \\\},
\par $$ % and \\end\{displaymath\} here
\par and these are easily seen to be completely regular.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which produces\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19  For each {{\i a}} for which the Lebesgue-set {{\field{\*\fldinst{ EQ {\i L}\\s\\do4({\fs15 {\i a}})({\i f}){\u8800*}{\u8709*}}}{\fldrslt }}
} we define \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \fs19 \tab
{\field{\*\fldinst{ EQ {{\i B}}\\s\\do4({\fs15 {\i a}})({\i f})=\{{\i L}\\s\\do4({\fs15 {\i a}+{\i r}})({\i f}):{\i r}>0\}\\,}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 and these are easily seen to be completely regular. }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 That illustrates how to display an expression, but also shows that we\rquote ve got a lot more to learn about mathematical typesetting. Before we have a look at how to arrange symbols all over the show (e.g. the subscripting above) we must learn how to access the multitude of symbols that are used in mathematical texts.\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 {\*\bkmkstart BMsec_symbols}3.3{\*\bkmkend BMsec_symbols}  Using mathematical symbols\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} puts all the esoteric symbols of mathematics at our fingertips. They are all referenced by name, with the naming system being perfectly logical and systematic. None of the control words that access these symbols accepts an argument, but we\rquote ll soon see that some of them prepare {\plain L{\up6\fs19 A}T{\dn7 E}X} for something that might follow. For instance, when you ask for the symbol \lquote {{\field{\*\fldinst{ EQ  \\i \\su(,, )}}{\fldrslt }}
}\rquote  {\plain L{\up6\fs19 A}T{\dn7 E}X} is warned that any sub- or superscripts that follow should be positioned appropriately as limits to a summation. In keeping with the {\plain T{\dn7 E}X} spirit, none of this requires any additional work on your part.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We\rquote ll also see that some of the symbols behave differently depending on where they are used. For instance, when I ask for {{\field{\*\fldinst{ EQ  \\i \\su({\i i}=1,{\i n}, ){\i a}\\s\\do6({\fs20 {\i i}})}}{\fldrslt }}
} within the running text, the limits are places differently to when I ask for that expression to be displayed: \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ  \\i \\su({\i i}=1,{\i n}, ){\i a}\\s\\do6({\fs20 {\i i}}){    }.}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 Again, I typed nothing different here\emdash just asked for display math mode.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 It is important to note that {\i almost all of the special maths symbols are unavailable in ordinary paragraphing mode}. If you need to use one there, then use an in-line math expression {\b0\i0\scaps0\f3 $...$}.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 3.3.1  Symbols available from the keyboard\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 A small percentage of the available symbols can be obtained from just a single key press. They are {+} {\u8722?} {=} {<} {>} {|} {/} {(} {)} {[} {]} and {*}. Note that these must be typed {\i within maths mode} to be interpreted as math symbols.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Of course, all of {{\i a}}\endash {{\i z}}, {{\i A}}\endash {{\i Z}}, the numerals {0,1,2,\u8230?,9} and the punctuation characters {,} {;} and {:} are available directly from the keyboard. Alphabetic letters will be assumed to be variables that are to be italicised, unless told otherwise{\cs62\super\chftn}
{\*\footnote\pard \s65\ql\fi-113\li397\lin397\f0\fs24{\cs62\super\chftn} See section {\field{\*\fldinst{\lang1024 REF BMsec_mathtext \\* MERGEFORMAT }}{\fldrslt{3.4.6}}}}
. The numerals receive no special attention, appearing precisely as in normal paragraphing mode. The punctuation symbols are still set in standard roman type when read in maths mode, but a little space is left after them so that expressions like {{\field{\*\fldinst{ EQ \{{\i x}\\s\\do6({\fs20 {\i i}}):{\i i}=1\\,2\\,\u8230?\\,10\}}}{\fldrslt }}
} look like they should. Note that this means that normal sentence punctuation should not migrate into an expression.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 3.3.2  Greek letters\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Tables {\field{\*\fldinst{\lang1024 REF BMtab_lgreek \\* MERGEFORMAT }}{\fldrslt{3.1}}} and {\field{\*\fldinst{\lang1024 REF BMtab_ugreek \\* MERGEFORMAT }}{\fldrslt{3.2}}} show the control sequences that produce the letters of the Greek alphabet. We see that a lowercase Greek letter is simply is accessed by typing the control word of the same name as the symbol, using all lowercase letters. To obtain an uppercase Greek letter, simply capitalise the {\i first} letter of its name.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Just as {\b0\i0\scaps0\f3 $mistake$} produces {{\i m}{\i i}{\i s}{\i t}{\i a}{\i k}{\i e}} because the letters are interpreted as variables, so too will {\b0\i0\scaps0\f3 $\\tai \\epsilon \\chi$} produce the incorrectly spaced {{\u964*}{\u949*}{\u967*}} if you try to type greek words like this. {\plain T{\dn7 E}X} can be taught to set Greek, but this is not the way. {{\u964*}{\u949*}{\u967*}}, incidentally, is the Greek word for \ldblquote art\rdblquote  and it is from the initials of the Greek letters constituting this word that the name {\plain T{\dn7 E}X} was derived. {\plain T{\dn7 E}X} is \ldblquote the art of typesetting\rdblquote .\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx768\cellx2271\cellx3239\cellx4942\cellx5576\cellx6945\cellx7713\cellx9216
{\pard\intbl\ql {{{\u945*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?alpha}\cell}
{\pard\intbl\ql {{{\u946*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?beta}\cell}
{\pard\intbl\ql {{{\u947*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?gamma}\cell}
{\pard\intbl\ql {{{\u948*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?delta}\cell}
\row}
{\trowd\cellx768\cellx2271\cellx3239\cellx4942\cellx5576\cellx6945\cellx7713\cellx9216
{\pard\intbl\ql {{{\u949*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?epsilon}\cell}
{\pard\intbl\ql {{{\u949*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?varepsilon}\cell}
{\pard\intbl\ql {{{\u950*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?zeta}\cell}
{\pard\intbl\ql {{{\u951*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?eta}\cell}
\row}
{\trowd\cellx768\cellx2271\cellx3239\cellx4942\cellx5576\cellx6945\cellx7713\cellx9216
{\pard\intbl\ql {{{\u920*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?theta}\cell}
{\pard\intbl\ql {{{\u977*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?vartheta}\cell}
{\pard\intbl\ql {{{\u953*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?iota}\cell}
{\pard\intbl\ql {{{\u954*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?kappa}\cell}
\row}
{\trowd\cellx768\cellx2271\cellx3239\cellx4942\cellx5576\cellx6945\cellx7713\cellx9216
{\pard\intbl\ql {{{\u955*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?lambda}\cell}
{\pard\intbl\ql {{{\u956*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?mu}\cell}
{\pard\intbl\ql {{{\u957*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?nu}\cell}
{\pard\intbl\ql {{{\u958*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?xi}\cell}
\row}
{\trowd\cellx768\cellx2271\cellx3239\cellx4942\cellx5576\cellx6945\cellx7713\cellx9216
{\pard\intbl\ql {{{\u960*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?pi}\cell}
{\pard\intbl\ql {{{\u982*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?varpi}\cell}
{\pard\intbl\ql {{{\u1009*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?rho}\cell}
{\pard\intbl\ql {{{\u1009*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?varrho}\cell}
\row}
{\trowd\cellx768\cellx2271\cellx3239\cellx4942\cellx5576\cellx6945\cellx7713\cellx9216
{\pard\intbl\ql {{{\u963*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sigma}\cell}
{\pard\intbl\ql {{{\u962*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?varsigma}\cell}
{\pard\intbl\ql {{{\u964*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?tau}\cell}
{\pard\intbl\ql {{{\u8593*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?upsilon}\cell}
\row}
{\trowd\cellx768\cellx2271\cellx3239\cellx4942\cellx5576\cellx6945\cellx7713\cellx9216
{\pard\intbl\ql {{{\u966*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?phi}\cell}
{\pard\intbl\ql {{{\u981*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?varphi}\cell}
{\pard\intbl\ql {{{\u967*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?chi}\cell}
{\pard\intbl\ql {{{\u968*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?psi}\cell}
\row}
{\trowd\cellx768\cellx2271
{\pard\intbl\ql {{{\u969*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?omega}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_lgreek}3.1{\*\bkmkend BMtab_lgreek}: \i0\scaps0\b0\f0 Lowercase Greek letters}{\field{\*\fldinst TC "3.1 \i0\scaps0\b0\f0 Lowercase Greek letters" \\f t}{\fldrslt }}\par
}{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb480 \fi0  \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx701\cellx2229\cellx2930\cellx4458\cellx5159\cellx6687\cellx7538\cellx9216
{\pard\intbl\ql {{{\u915*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Gamma}\cell}
{\pard\intbl\ql {{{\u916*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Delta}\cell}
{\pard\intbl\ql {{{\u964*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Theta}\cell}
{\pard\intbl\ql {{{\u923*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Lambda}\cell}
\row}
{\trowd\cellx701\cellx2229\cellx2930\cellx4458\cellx5159\cellx6687\cellx7538\cellx9216
{\pard\intbl\ql {{{\u926*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Xi}\cell}
{\pard\intbl\ql {{{\u928*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Pi}\cell}
{\pard\intbl\ql {{{\u931*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Sigma}\cell}
{\pard\intbl\ql {{{\u933*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Upsilon}\cell}
\row}
{\trowd\cellx701\cellx2229\cellx2930\cellx4458\cellx5159\cellx6687
{\pard\intbl\ql {{{\u934*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Phi}\cell}
{\pard\intbl\ql {{{\u936*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Psi}\cell}
{\pard\intbl\ql {{{\u937*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Omega}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_ugreek}3.2{\*\bkmkend BMtab_ugreek}: \i0\scaps0\b0\f0 Uppercase Greek letters}{\field{\*\fldinst TC "3.2 \i0\scaps0\b0\f0 Uppercase Greek letters" \\f t}{\fldrslt }}\par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 3.3.3  Calligraphic uppercase letters\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 The letters {{\i A},\u8230?,{\i Z}} are available through use of the style changing command {\b0\i0\scaps0\f3 \\cal}. This command behaves like the other style changing commands {\b0\i0\scaps0\f3 \\em}, {\b0\i0\scaps0\f3 \\it}, etc. so its scope must be delimited as with them. Thus we can type\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par ... for the filter $\\cal F$ we have $\\varphi(\{\\cal F\}) = \\cal G$.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 to obtain\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 for the filter {{\i F}} we have {{\u981*}({{\i F}})={\i G}}. }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 There is no need to tabulate all the calligraphic letters, since they are all obtained by just a type style changing command. We will just list them so that we can see, for reference purposes, what they all look like. Here they are:\par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{{\i A}}{{\i B}}{{\i C}}{{\i D}}{{\i E}}{{\i F}}{{\i G}}{{\i H}}{{\i I}}{{\i J}}{{\i K}}{{\i L}}{{\i M}}{{\i N}}{{\i O}}{{\i P}}{{\i Q}}{{\i R}}{{\i S}}{{\i T}}{{\i U}}{{\i V}}{{\i W}}{{\i X}}{{\i Y}}{\i Z}\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 3.3.4  Binary operators\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} has been taught to recognise binary operators and set the appropriate space either side of one\emdash i.e., it sets the first argument followed by a little space, then the operator followed by the same little space and finally the second argument. Table\~{\field{\*\fldinst{\lang1024 REF BMtab_binops \\* MERGEFORMAT }}{\fldrslt{3.3}}} shows the binary operators that are available via {\plain L{\up6\fs19 A}T{\dn7 E}X} control words (recall that the binary operators {+}, {\u8722?}, and {*} can be typed from the keyboard). Here are some examples of their use: {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx5020\cellx9220
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx5020\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $a+b$}}\cell}
{\pard\intbl\ql {{{\i a}+{\i b}}}\cell}
\row}
{\trowd\cellx5020\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $(a+b) \\ otimes c$}}\cell}
{\pard\intbl\ql {{({\i a}+{\i b}){\f5\u8855*}{\i c}}}\cell}
\row}
{\trowd\cellx5020\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $(a \\vee b) \\wedge c$}}\cell}
{\pard\intbl\ql {{({\i a}{\f5\u8744*}{\i b}){\f5\u8743*}{\i c}}}\cell}
\row}
{\trowd\cellx5020\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $X - (A \\cap B) = (X-A) \\cup (X-B)$}}\cell}
{\pard\intbl\ql {{{\i X}\u8722?({\i A}{\u8745*}{\i B})=({\i X}\u8722?{\i A}){\f5\u8746*}({\i X}\u8722?{\i B})}}\cell}
\row}
}\par
}}{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb360 \fi0 \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx692\cellx2037\cellx2789\cellx4193\cellx5360\cellx7179\cellx7871\cellx9216
{\pard\intbl\ql {{{\u177*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?pm}\cell}
{\pard\intbl\ql {{{\u8745*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?cap}\cell}
{\pard\intbl\ql {{{\u8900*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?diamond}\cell}
{\pard\intbl\ql {{{\f5\u8853*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?oplus}\cell}
\row}
{\trowd\cellx692\cellx2037\cellx2789\cellx4193\cellx5360\cellx7179\cellx7871\cellx9216
{\pard\intbl\ql {{{\f5\u8723*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?mp}\cell}
{\pard\intbl\ql {{{\f5\u8746*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?cup}\cell}
{\pard\intbl\ql {{{\f5\u9651*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigtriangleup}\cell}
{\pard\intbl\ql {{{\f5\u8854*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?ominus}\cell}
\row}
{\trowd\cellx692\cellx2037\cellx2789\cellx4193\cellx5360\cellx7179\cellx7871\cellx9216
{\pard\intbl\ql {{{\u215*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?times}\cell}
{\pard\intbl\ql {{{\u8846*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?uplus}\cell}
{\pard\intbl\ql {{{\f5\u9661*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigtriangledown}\cell}
{\pard\intbl\ql {{{\f5\u8855*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?otimes}\cell}
\row}
{\trowd\cellx692\cellx2037\cellx2789\cellx4193\cellx5360\cellx7179\cellx7871\cellx9216
{\pard\intbl\ql {{{\u247*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?div}\cell}
{\pard\intbl\ql {{{\u8851*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sqcap}\cell}
{\pard\intbl\ql {{{\u9667*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?triangleleft}\cell}
{\pard\intbl\ql {{{\f5\u8856*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?oslash}\cell}
\row}
{\trowd\cellx692\cellx2037\cellx2789\cellx4193\cellx5360\cellx7179\cellx7871\cellx9216
{\pard\intbl\ql {{{\u8727*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?ast}\cell}
{\pard\intbl\ql {{{\u8852*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sqcup}\cell}
{\pard\intbl\ql {{{\u9657*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?triangleright}\cell}
{\pard\intbl\ql {{{\f5\u8857*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?odot}\cell}
\row}
{\trowd\cellx692\cellx2037\cellx2789\cellx4193\cellx5360\cellx7179\cellx7871\cellx9216
{\pard\intbl\ql {{{\u8902*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?star}\cell}
{\pard\intbl\ql {{{\f5\u8744*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?vee}\cell}
{\pard\intbl\ql {{{\f5\u8743*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?wedge}\cell}
{\pard\intbl\ql {{{\u9675*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigcirc}\cell}
\row}
{\trowd\cellx692\cellx2037\cellx2789\cellx4193\cellx5360\cellx7179\cellx7871\cellx9216
{\pard\intbl\ql {{\'86}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?dagger}\cell}
{\pard\intbl\ql {{{\u8726*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?setminus}\cell}
{\pard\intbl\ql {{{\f5\u8720*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?amalg}\cell}
{\pard\intbl\ql {{{\u8728*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?circ}\cell}
\row}
{\trowd\cellx692\cellx2037\cellx2789\cellx4193\cellx5360\cellx7179\cellx7871\cellx9216
{\pard\intbl\ql {{\'87}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?ddagger}\cell}
{\pard\intbl\ql {{{\u8901*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?cdot}\cell}
{\pard\intbl\ql {{{\u8768*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?wr}\cell}
{\pard\intbl\ql {{{\u8226*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bullet}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_binops}3.3{\*\bkmkend BMtab_binops}: \i0\scaps0\b0\f0 Binary Operation Symbols}{\field{\*\fldinst TC "3.3 \i0\scaps0\b0\f0 Binary Operation Symbols" \\f t}{\fldrslt }}\par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 3.3.5  Binary relations\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} has been taught to recognize the use of binary relations, too. Table\~{\field{\*\fldinst{\lang1024 REF BMtab_binrels \\* MERGEFORMAT }}{\fldrslt{3.4}}} shows those available via {\plain L{\up6\fs19 A}T{\dn7 E}X} control words. There are a few that you can obtain directly from the keyboard: {<}, {>}, {=}, and {|}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 To negate a symbol you can precede the control word that gives the symbol by a {\b0\i0\scaps0\f3 \\not}. Some symbols come with ready-made negations, which should be used above the {\b0\i0\scaps0\f3 \\not}\rquote ing method because the slope of the negating line is just slightly changed to look more pleasing. Thus {\b0\i0\scaps0\f3 \\notin} should be used above {\b0\i0\scaps0\f3 \\not\\in}, and {\b0\i0\scaps0\f3 \\neq} should be used above {\b0\i0\scaps0\f3 \\not =}.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 If negating a symbol produces a slash whose horizontal positioning is not to your liking, then use the math spacing characters described in section\~{\field{\*\fldinst{\lang1024 REF BMsec_mathspace \\* MERGEFORMAT }}{\fldrslt{3.4.12}}} to adjust it.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973\cellx7754\cellx9216
{\pard\intbl\ql {{{\u8804*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?leq}\cell}
{\pard\intbl\ql {{{\u8805*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?geq}\cell}
{\pard\intbl\ql {{{\u8801*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?equiv}\cell}
{\pard\intbl\ql {{{\u8871*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?models}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973\cellx7754\cellx9216
{\pard\intbl\ql {{{\u8826*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?prec}\cell}
{\pard\intbl\ql {{{\u8827*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?succ}\cell}
{\pard\intbl\ql {{{\f5\u8764*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sim}\cell}
{\pard\intbl\ql {{{\f5\u8869*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?perp}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973\cellx7754\cellx9216
{\pard\intbl\ql {{{\f5\u10927*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?preceq}\cell}
{\pard\intbl\ql {{{\f5\u10928*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?succeq}\cell}
{\pard\intbl\ql {{{\u8771*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?simeq}\cell}
{\pard\intbl\ql {{|}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?mid}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973\cellx7754\cellx9216
{\pard\intbl\ql {{{\f5\u8810*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?ll}\cell}
{\pard\intbl\ql {{{\f5\u8811*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?gg}\cell}
{\pard\intbl\ql {{{\u8781*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?asymp}\cell}
{\pard\intbl\ql {{{\f5\u8741*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?parallel}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973\cellx7754\cellx9216
{\pard\intbl\ql {{{\f5\u8834*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?subset}\cell}
{\pard\intbl\ql {{{\f5\u8835*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?supset}\cell}
{\pard\intbl\ql {{{\u8776*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?approx}\cell}
{\pard\intbl\ql {{{\u8904*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bowtie}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973\cellx7754\cellx9216
{\pard\intbl\ql {{{\f5\u8838*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?subseteq}\cell}
{\pard\intbl\ql {{{\f5\u8839*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?supseteq}\cell}
{\pard\intbl\ql {{{\u8773*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?cong}\cell}
{\pard\intbl\ql {{{\u8904*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Join}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973\cellx7754\cellx9216
{\pard\intbl\ql {{{\u8847*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sqsubset}\cell}
{\pard\intbl\ql {{{\u8848*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sqsupset}\cell}
{\pard\intbl\ql {{{\u8800*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?neq}\cell}
{\pard\intbl\ql {{{\f5\u8995*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?smile}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973\cellx7754\cellx9216
{\pard\intbl\ql {{{\u8849*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sqsubseteq}\cell}
{\pard\intbl\ql {{{\u8850*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sqsupseteq}\cell}
{\pard\intbl\ql {{{\u8784*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?doteq}\cell}
{\pard\intbl\ql {{{\f5\u8994*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?frown}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978\cellx5635\cellx6973
{\pard\intbl\ql {{{\f5\u8712*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?in}\cell}
{\pard\intbl\ql {{{\f5\u8715*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?ni}\cell}
{\pard\intbl\ql {{{\f5\u8733*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?propto}\cell}
\row}
{\trowd\cellx904\cellx2489\cellx3393\cellx4978
{\pard\intbl\ql {{{\u8866*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?vdash}\cell}
{\pard\intbl\ql {{{\u8867*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?dashv}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_binrels}3.4{\*\bkmkend BMtab_binrels}: \i0\scaps0\b0\f0 Binary relations}{\field{\*\fldinst TC "3.4 \i0\scaps0\b0\f0 Binary relations" \\f t}{\fldrslt }}\par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 3.3.6  Miscellaneous symbols\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Table\~{\field{\*\fldinst{\lang1024 REF BMtab_miscsym \\* MERGEFORMAT }}{\fldrslt{3.5}}} shows a number of general-purpose symbols. Remember that these are only available in maths mode. Note that {\b0\i0\scaps0\f3 \\imath} and {\b0\i0\scaps0\f3 \\jmath} should be used when you need to accent an {{\i i}} or a\~{{\i j}} in maths mode{\cs62\super\chftn}
{\*\footnote\pard \s65\ql\fi-113\li397\lin397\f0\fs24{\cs62\super\chftn} See section {\field{\*\fldinst{\lang1024 REF BMsec_mathacc \\* MERGEFORMAT }}{\fldrslt{3.3.10}}}}
\emdash you cannot use {\b0\i0\scaps0\f3 \\i} or {\b0\i0\scaps0\f3 \\j} that were available in paragraphing mode. To get a prime symbol, you can use {\b0\i0\scaps0\f3 \\prime} or you can just type {\b0\i0\scaps0\f3 '} when in maths mode, as in {\b0\i0\scaps0\f3 $f''(x)=x$} which produces {{\i f}''({\i x})={\i x}}.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx602\cellx1895\cellx2686\cellx4168\cellx5022\cellx6567\cellx7546\cellx9216
{\pard\intbl\ql {{{\u8501*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?aleph}\cell}
{\pard\intbl\ql {{'}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?prime}\cell}
{\pard\intbl\ql {{{\f5\u8704*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?forall}\cell}
{\pard\intbl\ql {{{\u8734*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?infty}\cell}
\row}
{\trowd\cellx602\cellx1895\cellx2686\cellx4168\cellx5022\cellx6567\cellx7546\cellx9216
{\pard\intbl\ql {{{\u295*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?hbar}\cell}
{\pard\intbl\ql {{{\u8709*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?emptyset}\cell}
{\pard\intbl\ql {{{\f5\u8707*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?exists}\cell}
{\pard\intbl\ql {{{\u9633*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Box}\cell}
\row}
{\trowd\cellx602\cellx1895\cellx2686\cellx4168\cellx5022\cellx6567\cellx7546\cellx9216
{\pard\intbl\ql {{{\u305*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?imath}\cell}
{\pard\intbl\ql {{{\f5\u8711*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?nabla}\cell}
{\pard\intbl\ql {{{\u8800*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?neg}\cell}
{\pard\intbl\ql {{{\u9653*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?triangle}\cell}
\row}
{\trowd\cellx602\cellx1895\cellx2686\cellx4168\cellx5022\cellx6567\cellx7546\cellx9216
{\pard\intbl\ql {{{\u567*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?jmath}\cell}
{\pard\intbl\ql {{{\u8730*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?surd}\cell}
{\pard\intbl\ql {{{\f5\u9837*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?flat}\cell}
{\pard\intbl\ql {{{\u9653*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?triangle}\cell}
\row}
{\trowd\cellx602\cellx1895\cellx2686\cellx4168\cellx5022\cellx6567\cellx7546\cellx9216
{\pard\intbl\ql {{{\u8467*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?ell}\cell}
{\pard\intbl\ql {{{\u8890*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?top}\cell}
{\pard\intbl\ql {{{\u9838*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?natural}\cell}
{\pard\intbl\ql {{{\u9827*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?clubsuit}\cell}
\row}
{\trowd\cellx602\cellx1895\cellx2686\cellx4168\cellx5022\cellx6567\cellx7546\cellx9216
{\pard\intbl\ql {{{\u8472*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?wp}\cell}
{\pard\intbl\ql {{{\f5\u8869*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bot}\cell}
{\pard\intbl\ql {{{\u9839*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sharp}\cell}
{\pard\intbl\ql {{{\u9830*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?diamondsuit}\cell}
\row}
{\trowd\cellx602\cellx1895\cellx2686\cellx4168\cellx5022\cellx6567\cellx7546\cellx9216
{\pard\intbl\ql {{{\u8476*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Re}\cell}
{\pard\intbl\ql {{|}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?\emdash }\cell}
{\pard\intbl\ql {{\\}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?backslash}\cell}
{\pard\intbl\ql {{{\u9829*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?heartsuit}\cell}
\row}
{\trowd\cellx602\cellx1895\cellx2686\cellx4168\cellx5022\cellx6567\cellx7546\cellx9216
{\pard\intbl\ql {{{\u8465*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Im}\cell}
{\pard\intbl\ql {{{\f5\u8736*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?angle}\cell}
{\pard\intbl\ql {{{\u8706*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?partial}\cell}
{\pard\intbl\ql {{{\u9824*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?spadesuit}\cell}
\row}
{\trowd\cellx602\cellx1895
{\pard\intbl\ql {{{\u8487*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?mho}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_miscsym}3.5{\*\bkmkend BMtab_miscsym}: \i0\scaps0\b0\f0 Miscellaneous symbols}{\field{\*\fldinst TC "3.5 \i0\scaps0\b0\f0 Miscellaneous symbols" \\f t}{\fldrslt }}\par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 3.3.7  Arrow symbols\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} has a multitude of arrow symbols, which it will set the correct space around. Note that vertical arrows can all be used as delimiters\emdash see section\~{\field{\*\fldinst{\lang1024 REF BMsec_delims \\* MERGEFORMAT }}{\fldrslt{3.3.8}}}. The available symbols are listed in table\~{\field{\*\fldinst{\lang1024 REF BMtab_arrows \\* MERGEFORMAT }}{\fldrslt{3.6}}}.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u8592*}}}{\fldrslt }}
}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?leftarrow}\cell}
{\pard\intbl\ql {{{\f5\u10229*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?longleftarrow}\cell}
{\pard\intbl\ql {{{\u8593*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?uparrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\u8656*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Leftarrow}\cell}
{\pard\intbl\ql {{{\f5\u10232*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Longleftarrow}\cell}
{\pard\intbl\ql {{{\u8657*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Uparrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u8594*}}}{\fldrslt }}
}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?rightarrow}\cell}
{\pard\intbl\ql {{{\f5\u10230*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?longrightarrow}\cell}
{\pard\intbl\ql {{{\u8595*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?downarrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\f5\u8658*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Rightarrow}\cell}
{\pard\intbl\ql {{{\f5\u10233*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Longrightarrow}\cell}
{\pard\intbl\ql {{{\u8659*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Downarrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u8596*}}}{\fldrslt }}
}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?leftrightarrow}\cell}
{\pard\intbl\ql {{{\f5\u10231*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?longleftrightarrow}\cell}
{\pard\intbl\ql {{{\u8597*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?updownarrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\f5\u8660*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Leftrightarrow}\cell}
{\pard\intbl\ql {{{\f5\u10234*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Longleftrightarrow}\cell}
{\pard\intbl\ql {{{\u8661*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Updownarrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\u8614*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?mapsto}\cell}
{\pard\intbl\ql {{{\f5\u10236*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?longmapsto}\cell}
{\pard\intbl\ql {{{\f5\u8599*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?nearrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\u8617*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?hookleftarrow}\cell}
{\pard\intbl\ql {{{\u8618*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?hookrightarrow}\cell}
{\pard\intbl\ql {{{\f5\u8600*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?searrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u8636*}}}{\fldrslt }}
}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?leftharpoonup}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u8640*}}}{\fldrslt }}
}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?rightharpoonup}\cell}
{\pard\intbl\ql {{{\f5\u8601*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?swarrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666\cellx7609\cellx9215
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u8637*}}}{\fldrslt }}
}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?leftharpoondown}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u8641*}}}{\fldrslt }}
}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?rightharpoondown}\cell}
{\pard\intbl\ql {{{\f5\u8598*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?nwarrow}\cell}
\row}
{\trowd\cellx1305\cellx3273\cellx4638\cellx6666
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\o ({\up4 {\u8636*}},{\dn4 {\u8641*}}) }}{\fldrslt }}
}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?rightleftharpoons}\cell}
{\pard\intbl\ql {{{\u8669*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?leadsto}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_arrows}3.6{\*\bkmkend BMtab_arrows}: \i0\scaps0\b0\f0 Arrow symbols}{\field{\*\fldinst TC "3.6 \i0\scaps0\b0\f0 Arrow symbols" \\f t}{\fldrslt }}\par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 {\*\bkmkstart BMsec_delims}3.3.8{\*\bkmkend BMsec_delims}  Expression delimiters\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 A pair of delimters often enclose an expression, as in \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ  \\b \\bc\\[ ({ \\a \\ac \\co2 ({\i a}\\s\\do6({\fs20 11}),{\i a}\\s\\do6({\fs20 12}),{\i a}\\s\\do6({\fs20 21}),{\i a}\\s\\do6({\fs20 22}))}){{    }and{    }}{\i f}({\i x})= \\b \\lc\\\{ ({ \\a \\al \\co2 ({\i x},{if\~}\~x\~<\~1\~,x\\s\\up6({\fs20 2}),\~{if\~}\~x\~{\u8805*}1 )}){    }.}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} will scale delimiters to the correct size (determined by what they enclose) for you, if you ask it to. There are times when you don\rquote t want a delimiter to be scaled, so it is left up to you to ask for scaling.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 To ask that a delimter be scaleable, you precede it by {\b0\i0\scaps0\f3 \\left} or {\b0\i0\scaps0\f3 \\right} according as it is the left or right member of the pair. Scaled delimiters must be balanced correctly. It sometimes occurs, as in the right-hand example above, that only one member of a delimiting pair is to be visible. For this purpose, use the commands {\b0\i0\scaps0\f3 \\left.} and {\b0\i0\scaps0\f3 \\right.} which will produce no visible delimiter but can be used to correctly balance the delimiters in an expression. For examples of the use of delimiters, see section\~{\field{\*\fldinst{\lang1024 REF BMsec_arrays \\* MERGEFORMAT }}{\fldrslt{3.4.11}}} where we learn about arrays.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Table\~{\field{\*\fldinst{\lang1024 REF BMtab_delims \\* MERGEFORMAT }}{\fldrslt{3.7}}} shows the symbols that {\plain L{\up6\fs19 A}T{\dn7 E}X} will recognise as delimiters, i.e. symbols that may follow a {\b0\i0\scaps0\f3 \\left} or a {\b0\i0\scaps0\f3 \\right}. Note that you have to use {\b0\i0\scaps0\f3 \\left\\\{} and {\b0\i0\scaps0\f3 \\right\\\}} in order to get scaled braces.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx757\cellx2318\cellx3294\cellx5074\cellx6196\cellx9218
{\pard\intbl\ql {{(}}\cell}
{\pard\intbl\ql {{(}}\cell}
{\pard\intbl\ql {{)}}\cell}
{\pard\intbl\ql {{)}}\cell}
{\pard\intbl\ql {{{\u8593*}}}\cell}
{\pard\intbl\ql {{\i0\scaps0\b0\f3 \u92?uparrow}}\cell}
\row}
{\trowd\cellx757\cellx2318\cellx3294\cellx5074\cellx6196\cellx9218
{\pard\intbl\ql {{[}}\cell}
{\pard\intbl\ql {]}\cell}
{\pard\intbl\ql {{]}}\cell}
{\pard\intbl\ql {]}\cell}
{\pard\intbl\ql {{{\u8595*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?downarrow}\cell}
\row}
{\trowd\cellx757\cellx2318\cellx3294\cellx5074\cellx6196\cellx9218
{\pard\intbl\ql {{\{}}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\\{}}\cell}
{\pard\intbl\ql {{\}}}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\\}}}\cell}
{\pard\intbl\ql {{{\u8597*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?updownarrow}\cell}
\row}
{\trowd\cellx757\cellx2318\cellx3294\cellx5074\cellx6196\cellx9218
{\pard\intbl\ql {{{\f5\u8970*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?lfloor}\cell}
{\pard\intbl\ql {{{\f5\u8971*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?rfloor}\cell}
{\pard\intbl\ql {{{\u8657*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Uparrow}\cell}
\row}
{\trowd\cellx757\cellx2318\cellx3294\cellx5074\cellx6196\cellx9218
{\pard\intbl\ql {{{\f5\u8968*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?lceil}\cell}
{\pard\intbl\ql {{{\f5\u8969*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?rceil}\cell}
{\pard\intbl\ql {{{\u8659*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Downarrow}\cell}
\row}
{\trowd\cellx757\cellx2318\cellx3294\cellx5074\cellx6196\cellx9218
{\pard\intbl\ql {{{\f5\u9001*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?langle}\cell}
{\pard\intbl\ql {{{\f5\u9002*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?rangle}\cell}
{\pard\intbl\ql {{{\u8661*}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?Updownarrow}\cell}
\row}
{\trowd\cellx757\cellx2318\cellx3294\cellx5074
{\pard\intbl\ql {{/}}\cell}
{\pard\intbl\ql {/}\cell}
{\pard\intbl\ql {{\\}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?backslash}\cell}
\row}
{\trowd\cellx757\cellx2318\cellx3294\cellx5074
{\pard\intbl\ql {{|}}\cell}
{\pard\intbl\ql {\emdash }\cell}
{\pard\intbl\ql {{|}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?\emdash }\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_delims}3.7{\*\bkmkend BMtab_delims}: \i0\scaps0\b0\f0 Delimiters}{\field{\*\fldinst TC "3.7 \i0\scaps0\b0\f0 Delimiters" \\f t}{\fldrslt }}\par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 3.3.9  Operators like {{\field{\*\fldinst{ EQ  \\i \\in(,, )}}{\fldrslt }}
} and {{\field{\*\fldinst{ EQ  \\i \\su(,, )}}{\fldrslt }}
}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 These behave differently when used in display-math mode as compared with in-text math mode. When used in text, they will appear in their small form and any limits provided will be set so as to reduce the overall height of the operator, as in {{\field{\*\fldinst{ EQ  \\i \\su({\i i}=1,{\i N}, ){\i f}\\s\\do6({\fs20 {\i i}})}}{\fldrslt }}
}. When used in display-math mode, {\plain L{\up6\fs19 A}T{\dn7 E}X} will choose to use the larger form and will not try to reduce the height of the operator, as in \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ  \\i \\su({\i i}=1,{\i N}, ){\i f}\\s\\do6({\fs20 {\i i}}){    }.}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Table\~{\field{\*\fldinst{\lang1024 REF BMtab_bigops \\* MERGEFORMAT }}{\fldrslt{3.8}}} describes what variable-size symbols are available, showing both the small (in text) and the large (displayed) form of each. In section\~{\field{\*\fldinst{\lang1024 REF BMsec_subsup \\* MERGEFORMAT }}{\fldrslt{3.4.1}}} we will learn how to place limits on these operators.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx2015\cellx2881\cellx5049\cellx5991\cellx8236\cellx9217
{\pard\intbl\ql {{{{\field{\*\fldinst{ EQ  \\i \\su(,, ) \\i \\su(,, )}}{\fldrslt }}
}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?sum}\cell}
{\pard\intbl\ql {{{{\u8899*}{\u8899*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigcap}\cell}
{\pard\intbl\ql {{{{\f5\u10752*}{\f5\u10752*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigodot}\cell}
\row}
{\trowd\cellx2015\cellx2881\cellx5049\cellx5991\cellx8236\cellx9217
{\pard\intbl\ql {{{{\field{\*\fldinst{ EQ  \\i \\pr(,, ) \\i \\pr(,, )}}{\fldrslt }}
}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?prod}\cell}
{\pard\intbl\ql {{{{\u8898*}{\u8898*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigcup}\cell}
{\pard\intbl\ql {{{{\f5\u10754*}{\f5\u10754*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigotimes}\cell}
\row}
{\trowd\cellx2015\cellx2881\cellx5049\cellx5991\cellx8236\cellx9217
{\pard\intbl\ql {{{{\f5\u8720*}{\f5\u8720*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?coprod}\cell}
{\pard\intbl\ql {{{{\f5\u10758*}{\f5\u10758*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigsqcup}\cell}
{\pard\intbl\ql {{{{\f5\u10753*}{\f5\u10753*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigoplus}\cell}
\row}
{\trowd\cellx2015\cellx2881\cellx5049\cellx5991\cellx8236\cellx9217
{\pard\intbl\ql {{{{\field{\*\fldinst{ EQ  \\i \\in(,, ) \\i \\in(,, )}}{\fldrslt }}
}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?int}\cell}
{\pard\intbl\ql {{{{\u8897*}{\u8897*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigvee}\cell}
{\pard\intbl\ql {{{{\f5\u10756*}{\f5\u10756*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?biguplus}\cell}
\row}
{\trowd\cellx2015\cellx2881\cellx5049\cellx5991
{\pard\intbl\ql {{{{\f5\u8750*}{\f5\u8750*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?oint}\cell}
{\pard\intbl\ql {{{{\u8896*}{\u8896*}}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bigwedge}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_bigops}3.8{\*\bkmkend BMtab_bigops}: \i0\scaps0\b0\f0 Variable-sized symbols}{\field{\*\fldinst TC "3.8 \i0\scaps0\b0\f0 Variable-sized symbols" \\f t}{\fldrslt }}\par
}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 {\*\bkmkstart BMsec_mathacc}3.3.10{\*\bkmkend BMsec_mathacc}  Accents\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 The accenting commands that we learned for paragraphing mode do not apply in maths mode. Consult table\~{\field{\*\fldinst{\lang1024 REF BMtab_mathacc \\* MERGEFORMAT }}{\fldrslt{3.9}}} to see how to accent a symbol in maths mode (all the examples there accent the symbol {{\i u}}, but they work with any letter). Remember that {{\i i}} and {{\i j}} should lose their dots when accented, so {\b0\i0\scaps0\f3 \\imath} and {\b0\i0\scaps0\f3 \\jmath} should be used.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 There also exist commands that give a \ldblquote wide hat\rdblquote  or a \ldblquote wide tilde\rdblquote  to their argument, {\b0\i0\scaps0\f3 \\widehat} and {\b0\i0\scaps0\f3 \\widetilde}.\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  \par
\fs19 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \fs19 \par
{\trowd\cellx791\cellx2399\cellx3190\cellx4798\cellx5463\cellx6945\cellx7673\cellx9218
{\pard\intbl\ql {{\'fb}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?hat\{u\}}\cell}
{\pard\intbl\ql {{\'fa}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?acute\{u\}}\cell}
{\pard\intbl\ql {{\u363u}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?bar\{u\}}\cell}
{\pard\intbl\ql {{{\f5\u775.}{\i u}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?dot\{u\}}\cell}
\row}
{\trowd\cellx791\cellx2399\cellx3190\cellx4798\cellx5463\cellx6945\cellx7673\cellx9218
{\pard\intbl\ql {{\u468u}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?check\{u\}}\cell}
{\pard\intbl\ql {{\'f9}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?grave\{u\}}\cell}
{\pard\intbl\ql {{{\f5 \u8407-}{\i u}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?vec\{u\}}\cell}
{\pard\intbl\ql {{\'fc}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?ddot\{u\}}\cell}
\row}
{\trowd\cellx791\cellx2399\cellx3190\cellx4798
{\pard\intbl\ql {{{\f5\u774u}{\i u}}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?breve\{u\}}\cell}
{\pard\intbl\ql {{\u361u}}\cell}
{\pard\intbl\ql {\i0\scaps0\b0\f3 \u92?tilde\{u\}}\cell}
\row}
} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 \fs19 {Table {\*\bkmkstart BMtab_mathacc}3.9{\*\bkmkend BMtab_mathacc}: \i0\scaps0\b0\f0 Math accents}{\field{\*\fldinst TC "3.9 \i0\scaps0\b0\f0 Math accents" \\f t}{\fldrslt }}\par
}\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb480 \fi0 3.4  Some common mathematical structures\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 In this section we shall begin to learn how to manipulate all the symbols listed in section\~{\field{\*\fldinst{\lang1024 REF BMsec_symbols \\* MERGEFORMAT }}{\fldrslt{3.3}}}. Indeed, by the end of this section we\rquote ll be able to typeset some quite large expressions. In the section following this we will learn how use various alignment environments that allow us to prepare material like multi-line expressions and arrays.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 {\*\bkmkstart BMsec_subsup}3.4.1{\*\bkmkend BMsec_subsup}  Subscripts and superscripts\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Specifying a sub- or superscript is as easy as you\rquote d hope\emdash you just give an indication that you want a sub- or superscript to the last expression and provide the material to be placed there, and {\plain L{\up6\fs19 A}T{\dn7 E}X} will position things correctly. So sub- and superscripting a single symbol, an operator, or a big array all involve the same input, and {\plain L{\up6\fs19 A}T{\dn7 E}X} places the material according to what the expression is that is being sub- or superscripted: \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ {\i x}\\s\\up6({\fs20 2}){    }\\,{    } \\i \\pr({\i i}=1,{\i N}, ){\i X}\\s\\do6({\fs20 {\i i}}){    }\\,{    } \\b \\bc\\[ ({ \\a \\ac \\co3 ({\i a}\\s\\do6({\fs20 11}),{\i a}\\s\\do6({\fs20 12}),{\i a}\\s\\do6({\fs20 13}),{\i a}\\s\\do6({\fs20 21}),{\i a}\\s\\do6({\fs20 22}),{\i a}\\s\\do6({\fs20 23}),{\i a}\\s\\do6({\fs20 31}),{\i a}\\s\\do6({\fs20 32}),{\i a}\\s\\do6({\fs20 33}))})\\s\\up17({\fs20 2}){    }.}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 To tell {\plain L{\up6\fs19 A}T{\dn7 E}X} that you want a single character set as a superscript to the last expression, you just type a {\b0\i0\scaps0\f3 ^} before it. The \ldblquote last expression\rdblquote  is the preceding group or, if there is no preceding group, the single character or symbol that the {\b0\i0\scaps0\f3 ^} follows:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $x^2$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i x}\\s\\up4({\fs15 2})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $a^b$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i a}\\s\\up4({\fs15 {\i b}})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $Y^X$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i Y}\\s\\up4({\fs15 {\i X}})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\gamma^2$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u947*}\\s\\up4({\fs15 2})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $(A+B)^2$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ ({\i A}+{\i B})\\s\\up4({\fs15 2})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\left[ \\frac\{x^2+1\}\{x^2 + y^2\} \\right]^n$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\b \\bc\\[ ( \\F({\i x}\\s\\up4({\fs15 2})+1,{\i x}\\s\\up4({\fs15 2})+{\i y}\\s\\up4({\fs15 2})))\\s\\up13({\fs15 {\i n}})}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 Subscripts of a single character are equally easy\emdash you just use the underscore character {\b0\i0\scaps0\f3 _} where you used {\b0\i0\scaps0\f3 ^} for superscripting:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx6113\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx6113\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $x_2$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i x}\\s\\do4({\fs15 2})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx6113\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $x_i$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i x}\\s\\do4({\fs15 {\i i}})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx6113\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\Gamma_1(x)$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u915*}\\s\\do4({\fs15 1})({\i x})}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 Now let\rquote s see how to set a sub- or superscript that consists of more than just one character. This is no more difficult than before if we remember the following rule: {\i {\b0\i0\scaps0\f3 _} and {\b0\i0\scaps0\f3 ^} set the group that follows them as a sub- and superscripts to the group that precedes the sub- and superscript symbols.} We see now now that our initial examples worked by considering a single character to be a group by itself. Here are some examples:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $a^2b^3$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i a}\\s\\up4({\fs15 2}){\i b}\\s\\up4({\fs15 3})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $2^\{21\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ 2\\s\\up4({\fs15 21})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $2^21$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ 2\\s\\up4({\fs15 2})1}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $a^\{x+1\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i a}\\s\\up4({\fs15 {\i x}+1})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $a^\{x^2+1\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i a}\\s\\up4({\fs15 {\i x}\\s\\up3({\fs12 2})+1})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $(x+1)^3$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ ({\i x}+1)\\s\\up4({\fs15 3})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\Gamma_\{\\alpha\\beta\\gamma\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u915*}\\s\\do4({\fs15 {\u945*}{\u946*}{\u947*}})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5111\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\{\}_1A_2$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {}\\s\\do4({\fs15 1}){\i A}\\s\\do4({\fs15 2})}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 In the very last example we see a case of setting a subscript to an empty group, which resulted in a kind of \ldblquote pre-subscript\rdblquote . With some imagination this can be put to all sorts of uses.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 In all of the above examples the sub- and superscripts were set to single-character groups. Nowhere did we group an expression before sub- or superscripting it. Even in setting the expression {{\field{\*\fldinst{ EQ ({\i x}+1)\\s\\up6({\fs20 3})}}{\fldrslt }}
}, the superscript {{\field{\*\fldinst{ EQ {}\\s\\up6({\fs20 3})}}{\fldrslt }}
} was really only set to the character {)}. If we had wanted to group the {({\i x}+1)} before setting the superscript, we would have typed {\b0\i0\scaps0\f3 $\{(x+1)\}^3$} which gives {{\field{\*\fldinst{ EQ {({\i x}+1)}\\s\\up6({\fs20 3})}}{\fldrslt }}
}, with the superscript slightly raised. One has to go to this trouble because, to most people, something like {{\field{\*\fldinst{ EQ ({\i x}\\s\\up6({\fs20 {\i a}}))\\s\\up6({\fs20 {\i b}})}}{\fldrslt }}
} is just as acceptable and as readable as {{\field{\*\fldinst{ EQ {({\i x}\\s\\up6({\fs20 {\i a}}))}\\s\\up6({\fs20 {\i b}})}}{\fldrslt }}
}. It also has the advantage of aligning the base lines in expressions such as \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ ({\i a}{\i b})\\s\\up6({\fs20 \u8722?2})=[({\i a}{\i b})\\s\\up6({\fs20 \u8722?1})]\\s\\up6({\fs20 2})=[{\i b}\\s\\up6({\fs20 \u8722?1}){\i a}\\s\\up6({\fs20 \u8722?1})]\\s\\up6({\fs20 2})={\i b}\\s\\up6({\fs20 \u8722?1}){\i a}\\s\\up6({\fs20 \u8722?1}){\i b}\\s\\up6({\fs20 \u8722?1}){\i a}\\s\\up6({\fs20 \u8722?1})}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 which looks more pleasing than if we use additional grouping to force \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ {({\i a}{\i b})}\\s\\up6({\fs20 \u8722?2})={[{({\i a}{\i b})}\\s\\up6({\fs20 \u8722?1})]}\\s\\up6({\fs20 2})={[{\i b}\\s\\up6({\fs20 \u8722?1}){\i a}\\s\\up6({\fs20 \u8722?1})]}\\s\\up6({\fs20 2})={\i b}\\s\\up6({\fs20 \u8722?1}){\i a}\\s\\up6({\fs20 \u8722?1}){\i b}\\s\\up6({\fs20 \u8722?1}){\i a}\\s\\up6({\fs20 \u8722?1}){    }\\,}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 and the latter has rather more braces in it that require balancing.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Here are some more examples, showing how {\plain L{\up6\fs19 A}T{\dn7 E}X} will set things just as we want without any further work on our part:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx5229\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx5229\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $x^\{y^z\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i x}\\s\\up4({\fs15 {\i y}\\s\\up3({\fs12 {\i z}})})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5229\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $2^\{(2^2)\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ 2\\s\\up4({\fs15 (2\\s\\up3({\fs12 2}))})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5229\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $2^\{2^\{2^\{\\aleph_0\}\}\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ 2\\s\\up4({\fs15 2\\s\\up3({\fs12 2\\s\\up3({\fs10 {\u8501*}\\s\\do2({\fs8 0})})})})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5229\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\Gamma^\{z_c^d\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u915*}\\s\\up4({\fs15 {\i z}\\s\\up({\fs12 {\i d},{\i c}})})}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 We can also make use of empty groups in order to stagger sub- and superscripts to an expression, as in\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par $\\Gamma_\{\\alpha\\beta\}\{\}^\{\\gamma\}\{\}_\\delta$
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which will yield\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {{\field{\*\fldinst{ EQ {\u915*}\\s\\do4({\fs15 {\u945*}{\u946*}}){}\\s\\up4({\fs15 {\u947*}}){}\\s\\do4({\fs15 {\u948*}})}}{\fldrslt }}
} }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 One can specify the sub- and superscripts to a group in any order, but it is best to be consistent. The most natural order seems to be to have subscripts first, but you may think otherwise. It is also a good idea to always include your sub- and superscripts in braces (i.e. make them a group), whether they consist of just a single character or not. This enhances readability and also helps avoid the unfortunate case where you believe that a particular control word gives a single symbol yet it really is defined in terms of several.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 3.4.2  Primes\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} provides the control word {\b0\i0\scaps0\f3 \\prime} ({'}) for priming symbols. Note that it is not automatically at the superscript height, so that to get {{\field{\*\fldinst{ EQ {\i f}\\s\\up6({\fs20 '})}}{\fldrslt }}
} you would have to type\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par $f^\\prime$ .
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 To make lighter work of this, {\plain L{\up6\fs19 A}T{\dn7 E}X} will interpret a right-quote character as a prime if used in maths mode. Thus we can type\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par $f'(g(x)) g'(x) h''(x)$
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 in order to get\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {{\i f}'({\i g}({\i x})){\i g}'({\i x}){\i h}''({\i x}){    }.} }}\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb180 \fi0 3.4.3  Fractions\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} provides the {\b0\i0\scaps0\f3 \\frac} command that accepts two arguments: the numerator and the denominator (in that order). Before we look at examples of its use, let us just note that many simple in-text fractions are often better written in the form {{\scaps0\b0\i num}/{\scaps0\b0\i den}}, as with {3/8} which can be typed as {\b0\i0\scaps0\f3 $3/8$}. This is also often the better form for a fraction that occurs {\i within} some expression.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4280\cellx9220
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4280\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\frac\{x+1\}\{x+2\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\F({\i x}+1,{\i x}+2)}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4280\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\frac\{1\}\{x^2+1\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\F(1,{\i x}\\s\\up4({\fs15 2})+1)}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4280\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\frac\{1+x^2\}\{x^2+y^2\} + x^2 y$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\F(1+{\i x}\\s\\up4({\fs15 2}),{\i x}\\s\\up4({\fs15 2})+{\i y}\\s\\up4({\fs15 2}))+{\i x}\\s\\up4({\fs15 2}){\i y}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4280\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\frac\{1\}\{1 + \\frac\{x\}\{2\}\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\F(1,1+ \\F({\i x},2))}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4280\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\frac\{1\}\{1+x/2\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\F(1,1+{\i x}/2)}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 3.4.4  Roots\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 The {\b0\i0\scaps0\f3 \\sqrt} command accepts two arguments. The first, and optional, argument specifies what order of root you desire if it is anything other than the square root. The second, and mandatory, argument specifies the expression that the root sign should enclose:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4322\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4322\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\sqrt\{a+b\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\R(,{\i a}+{\i b})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4322\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\sqrt[5]\{a+b\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\R(5,{\i a}+{\i b})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4322\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\sqrt[n]\{\\frac\{1+x\}\{1+x^2\}\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\R({\i n}, \\F(1+{\i x},1+{\i x}\\s\\up4({\fs15 2})))}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4322\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\frac\{\\sqrt\{x+1\}\} \{\\sqrt[3]\{x^3+1\}\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\F( \\R(,{\i x}+1), \\R(3,{\i x}\\s\\up4({\fs15 3})+1))}}{\fldrslt }}
}}\cell}
\row}
}\par
}}}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 3.4.5  Ellipsis\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Simply typing three periods in a row will not give the correct spacing of the periods if it is an ellipsis that is desired. So {\plain L{\up6\fs19 A}T{\dn7 E}X} provides the commands {\b0\i0\scaps0\f3 \\ldots} and {\b0\i0\scaps0\f3 \\cdots}. Centered ellipsis should be used between symbols like {+}, {\u8722?}, {*}, {{\u215*}}, and {=}. Here are some examples:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4964\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4964\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $a_1+ \\cdots + a_n$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i a}\\s\\do4({\fs15 1})+{\u8943*}+{\i a}\\s\\do4({\fs15 {\i n}})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4964\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $x_1 \\times x_2 \\times \\cdots \\times x_n$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i x}\\s\\do4({\fs15 1}){\u215*}{\i x}\\s\\do4({\fs15 2}){\u215*}{\u8943*}{\u215*}{\i x}\\s\\do4({\fs15 {\i n}})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4964\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $v_1 = v_2 = \\cdots = v_n = 0$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i v}\\s\\do4({\fs15 1})={\i v}\\s\\do4({\fs15 2})={\u8943*}={\i v}\\s\\do4({\fs15 {\i n}})=0}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4964\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $f(x_1,\\ldots,x_n) = 0$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i f}({\i x}\\s\\do4({\fs15 1})\\,\u8230?\\,{\i x}\\s\\do4({\fs15 {\i n}}))=0}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 {\*\bkmkstart BMsec_mathtext}3.4.6{\*\bkmkend BMsec_mathtext}  Text within an expression\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 One can use the {\b0\i0\scaps0\f3 \\mbox} command to insert normal text into an expression. This command forces {\plain L{\up6\fs19 A}T{\dn7 E}X} temporarily out of maths mode, so that its argument will be treated as normal text. It\rquote s use is simple, but we must be wary on one count: remember that {\plain L{\up6\fs19 A}T{\dn7 E}X} ignores all space characters when in maths mode; so to surround words in an expression that were placed by an {\b0\i0\scaps0\f3 \\mbox} command by space you must include the space in the {\b0\i0\scaps0\f3 \\mbox} argument.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4910\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4910\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $f_i(x) \\leq 0 \\mbox\{ for \} x \\in I$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i f}\\s\\do4({\fs15 {\i i}})({\i x}){\u8804*}0{\~for\~}{\i x}{\f5\u8712*}{\i I}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4910\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\Gamma(n)=(n-1)! \\mbox\{ when $n$ is an integer\}$}}\cell}
{\pard\intbl\ql {{{\u915*}({\i n})=({\i n}\u8722?1)!{\~when\~{{\i n}} is an integer}}}\cell}
\row}
}\par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 In section\~{\field{\*\fldinst{\lang1024 REF BMsec_mathspace \\* MERGEFORMAT }}{\fldrslt{3.4.12}}} we\rquote ll learn of some special spacing commands that can be used in math mode. These are often very useful in positioning text within an expression, enhancing readability and logical layout.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 3.4.7  Log-like functions\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 There are a number of function names and operation symbols that should be set in normal (roman) type in an expression, such as in \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ {\i f}({\u920*})={\plain sin}{\u920*}+{\plain log}({\u920*}+1)\u8722?{\plain sinh}({\u920*}\\s\\up6({\fs20 2})+1)}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 and \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ \\a\\ac(lim,{\i h}{\u8594*}0) \\F({\plain sin}{\i h},{\i h})=1{    }.}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We know that simply typing {\b0\i0\scaps0\f3 $log\\theta$} would produce the incorrect result \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\i l}{\i o}{\i g}{\u920*}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 and that using {\b0\i0\scaps0\f3 $\\mbox\{log\}\\theta$} would leave us having to insert a little extra space between the log and the {{\u920*}} \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{log}{\u920*}{    }.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 So {\plain L{\up6\fs19 A}T{\dn7 E}X} provides a collection of \ldblquote log-like functions\rdblquote  defined as control sequences. Table\~{\field{\*\fldinst{\lang1024 REF BMtab_loglike \\* MERGEFORMAT }}{\fldrslt{3.10}}} shows those that are available. Here are some examples of their use:\par
{\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi0  {\par
\fs19 \i0\scaps0\b0\f3 {\pard\plain\s32\qc\sb120\sa0\keep\widctlpar\f0\fs24\sl240\slmult1 \fi0 \f3 \fs19 \par
{\trowd\cellx1263\cellx2389\cellx3447\cellx4505\cellx5768\cellx7031\cellx8089\cellx9215
{\pard\intbl\ql {\u92?arccos}\cell}
{\pard\intbl\ql {\u92?cos}\cell}
{\pard\intbl\ql {\u92?csc}\cell}
{\pard\intbl\ql {\u92?exp}\cell}
{\pard\intbl\ql {\u92?ker}\cell}
{\pard\intbl\ql {\u92?limsup}\cell}
{\pard\intbl\ql {\u92?min}\cell}
{\pard\intbl\ql {\u92?sinh}\cell}
\row}
{\trowd\cellx1263\cellx2389\cellx3447\cellx4505\cellx5768\cellx7031\cellx8089\cellx9215
{\pard\intbl\ql {\u92?arcsin}\cell}
{\pard\intbl\ql {\u92?cosh}\cell}
{\pard\intbl\ql {\u92?deg}\cell}
{\pard\intbl\ql {\u92?gcd}\cell}
{\pard\intbl\ql {\u92?lg}\cell}
{\pard\intbl\ql {\u92?ln}\cell}
{\pard\intbl\ql {\u92?Pr}\cell}
{\pard\intbl\ql {\u92?sup}\cell}
\row}
{\trowd\cellx1263\cellx2389\cellx3447\cellx4505\cellx5768\cellx7031\cellx8089\cellx9215
{\pard\intbl\ql {\u92?arctan}\cell}
{\pard\intbl\ql {\u92?cot}\cell}
{\pard\intbl\ql {\u92?det}\cell}
{\pard\intbl\ql {\u92?hom}\cell}
{\pard\intbl\ql {\u92?lim}\cell}
{\pard\intbl\ql {\u92?log}\cell}
{\pard\intbl\ql {\u92?sec}\cell}
{\pard\intbl\ql {\u92?tan}\cell}
\row}
{\trowd\cellx1263\cellx2389\cellx3447\cellx4505\cellx5768\cellx7031\cellx8089\cellx9215
{\pard\intbl\ql {\u92?arg}\cell}
{\pard\intbl\ql {\u92?coth}\cell}
{\pard\intbl\ql {\u92?dim}\cell}
{\pard\intbl\ql {\u92?inf}\cell}
{\pard\intbl\ql {\u92?liminf}\cell}
{\pard\intbl\ql {\u92?max}\cell}
{\pard\intbl\ql {\u92?sin}\cell}
{\pard\intbl\ql {\u92?tanh}\cell}
\row}
}} \par
\pard\plain\s30\ql\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \fi0 {Table {\*\bkmkstart BMtab_loglike}3.10{\*\bkmkend BMtab_loglike}: \i0\scaps0\b0\f0 Log-like functions}{\field{\*\fldinst TC "3.10 \i0\scaps0\b0\f0 Log-like functions" \\f t}{\fldrslt }}\par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb240 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $f(x)=\\sin x + \\log(x^2)$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i f}({\i x})={\plain sin}{\i x}+{\plain log}({\i x}\\s\\up4({\fs15 2}))}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\delta = \\min \\\{ \\delta_1, \\delta_2 \\\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u948*}={\plain min}\{{\u948*}\\s\\do4({\fs15 1})\\,{\u948*}\\s\\do4({\fs15 2})\}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\chi(X) = \\sup_\{x\\in X\} \\chi(x)$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u967*}({\i X})={\plain sup}\\s\\do4({\fs15 {\i x}{\f5\u8712*}{\i X}}){\u967*}({\i x})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4956\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\lim_\{n \\rightarrow \\infty\} S_n = \\gamma$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ \\a\\ac(lim,{\i n}{\u8594*}{\u8734*}){\i S}\\s\\do4({\fs15 {\i n}})={\u947*}}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 Notice how {\plain L{\up6\fs19 A}T{\dn7 E}X} does more than just set an operation like sup in roman type. It also knew where a subscript to that operator should go.\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 3.4.8  Over- and Underlining and bracing\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 The {\b0\i0\scaps0\f3 \\underline} command will place an unbroken line under its argument, and the {\b0\i0\scaps0\f3 \\overline} command will place an unbroken line over its argument. These two commands can also be used in normal paragraphing mode (but be careful: {\plain L{\up6\fs19 A}T{\dn7 E}X} will not break the line within an under- or overlined phrase, so don\rquote t go operating on large phrases).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 You can place horizontal braces above or below an expression by making that expression the argument of {\b0\i0\scaps0\f3 \\overbrace} or {\b0\i0\scaps0\f3 \\underbrace}. You can place a label on an overbrace (resp. underbrace) by superscripting (resp. subscripting the group defined by the bracing command.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx5020\cellx9220
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx5020\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\overline\{a+bi\} = a- bi$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\x\\to( {\i a}+{\i b}{\i i}) ={\i a}\u8722?{\i b}{\i i}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx5020\cellx9220
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\overline\{\\overline\{a+bi\}\} = a+bi$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\x\\to(  \\x\\to( {\i a}+{\i b}{\i i}) ) ={\i a}+{\i b}{\i i}}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 And some examples of horizontal bracing:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par $A^n=\\overbrace\{A \\times A \\times \\ldots \\times A\}^\{\\mbox\{$n$ terms\}\}$
\par 
\par $\\forall x \\underbrace\{\\exists y (y \\succ x)\}_\{\\mbox\{scope of $\\forall$\}\}$
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will produce \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ {\i A}\\s\\up6({\fs20 {\i n}})={{\i A}{\u215*}{\i A}{\u215*}\u8230?{\u215*}{\i A}}\\s\\up6({\fs20 {{{\i n}} terms}})}}{\fldrslt }}
\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi0 and \par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ {\f5\u8704*}{\i x}{{\f5\u8707*}{\i y}({\i y}{\u8827*}{\i x})}\\s\\do6({\fs20 {scope\~of\~{{\f5\u8704*}}}})}}{\fldrslt }}
\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 3.4.9  Stacking symbols\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\plain L{\up6\fs19 A}T{\dn7 E}X} allows you to set one symbol above another through the {\b0\i0\scaps0\f3 \\stackrel} command. This command accepts two arguments, and sets the first centrally above the second.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4990\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4990\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $X \\stackrel\{f^*\}\{\\rightarrow\}Y$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i X} \\a ({\fs15 {\i f}\\s\\up3({\fs12 *})},{\u8594*}) {\i Y}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4990\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $f(x) \\stackrel\{\\triangle\}\{=\} x^2 + 1$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\i f}({\i x}) \\a ({\fs15 {\u9653*}},=) {\i x}\\s\\up4({\fs15 2})+1}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 3.4.10  Operators; Sums, Integrals, etc.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Each of the operation symbols in table\~{\field{\*\fldinst{\lang1024 REF BMtab_bigops \\* MERGEFORMAT }}{\fldrslt{3.8}}} can occur with limits. They are specified as sub- and superscripts to the operator, and {\plain L{\up6\fs19 A}T{\dn7 E}X} will position them appropriately. In an in-text formula they will appear in more-or-less the usual scripting positions; but in a displayed formula they will be set below and above the symbol (which will also be a little larger). The following should give you an idea of how to use them:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4870\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4870\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\sum_\{i=1\}^\{N\} a_i$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\i \\su({\i i}=1,{\i N}, ){\i a}\\s\\do4({\fs15 {\i i}})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4870\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\int_a^b f$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\i ({\i a},{\i b}, ){\i f}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4870\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\oint_\{\\cal C\}f(x)\\,dx$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\f5\u8750*}\\s\\do4({\fs15 {\i C}}){\i f}({\i x}){\charscalex50\~}{\i d}{\i x}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4870\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\prod_\{\\alpha \\in A\} X_\\alpha$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\i \\pr({\u945*}{\f5\u8712*}{\i A},, ){\i X}\\s\\do4({\fs15 {\u945*}})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4870\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\lim_\{N\\rightarrow\\infty\}\\sum_\{i=1\}^\{N\}f(x_i)\\Delta x_i$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ \\a\\ac(lim,{\i N}{\u8594*}{\u8734*}) \\i \\su({\i i}=1,{\i N}, ){\i f}({\i x}\\s\\do4({\fs15 {\i i}})){\u916*}{\i x}\\s\\do4({\fs15 {\i i}})}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 We\rquote ll have more to say about the use of {\b0\i0\scaps0\f3 \\,} in section\~{\field{\*\fldinst{\lang1024 REF BMsec_mathspace \\* MERGEFORMAT }}{\fldrslt{3.4.12}}}. Let\rquote s have a look at each of those expressions when displayed:\par
\pard\plain\s11\ql\sb120\sa120\keep\widctlpar\f0\tqc\tx4610\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ  \\i \\su({\i i}=1,{\i N}, ){\i a}\\s\\do6({\fs20 {\i i}}){    }\\,{    } \\i ({\i a},{\i b}, ){\i f}{    }\\,{    }{\f5\u8750*}\\s\\do6({\fs20 {\i C}}){\i f}({\i x}){\charscalex50\~}{\i d}{\i x}{    }\\,{    } \\i \\pr({\u945*}{\f5\u8712*}{\i A},, ){\i X}\\s\\do6({\fs20 {\u945*}}){    }\\,{    }\\a\\ac(lim,{\i N}{\u8594*}{\u8734*}) \\i \\su({\i i}=1,{\i N}, ){\i f}({\i x}\\s\\do6({\fs20 {\i i}})){\u916*}{\i x}\\s\\do6({\fs20 {\i i}})}}{\fldrslt }}
\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb120 \fi0 {\*\bkmkstart BMsec_arrays}3.4.11{\*\bkmkend BMsec_arrays}  Arrays\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 The {\b0\i0\scaps0\f3 array} environment is provided for typesetting arrays and array-like material. It accepts two arguments, one optional and one mandatory. The optional argument specifies the vertical alignment of the array\emdash use {\b0\i0\scaps0\f3 t}, {\b0\i0\scaps0\f3 b}, or {\b0\i0\scaps0\f3 c} to align the top, bottom, or centre of the array with the centreline of the line it occurs on (the default being {\b0\i0\scaps0\f3 c}). The second argument is as for the {\b0\i0\scaps0\f3 tabular} environment: a series of {\b0\i0\scaps0\f3 l}, {\b0\i0\scaps0\f3 r}, and {\b0\i0\scaps0\f3 c}\rquote s that specify the number of columns and the justification of these columns. The body of the {\b0\i0\scaps0\f3 array} environment uses the same syntax as the {\b0\i0\scaps0\f3 tabular} environment to specify the individual entries of the array.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 For instance the input\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par ... let $A = \\begin\{array\}\{rrr\}
\par 12 & 3 & 4\\\\
\par -2 & 1 & 0\\\\
\par 3 & 7 & 9
\par \\end\{array\}$ ...
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will produce the output\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 let {{\field{\*\fldinst{ EQ {\i A}= \\b \\bc\\[ ({ \\a \\ar \\co3 (12,3,4,\u8722?2,1,0,3,7,9)})}}{\fldrslt }}
}}}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Note that we had to choose and supply the enclosing brackets ourselves (they are not placed for us so that we can use the {\b0\i0\scaps0\f3 array} environment for array-like material; also, we get to choose what type of brackets we want this way). As in the {\b0\i0\scaps0\f3 tabular} environment, the scope of a command given inside a matrix entry is restricted to that entry.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 We can use ellipsis within arrays as in the following example:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\det A = \\left| \\begin\{array\}\{cccc\}
\par a_\{11\} & a_\{12\} & \\cdots & a_\{1n\}\\\\
\par a_\{21\} & a_\{22\} & \\cdots & a_\{2n\}\\\\
\par \\vdots & \\vdots & \\ddots & \\vdots\\\\
\par a_\{m1\} & a_\{m2\} & \\cdots & a_\{mn\}
\par \\end\{array\} \\right|
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which produces\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {{\field{\*\fldinst{ EQ {\plain det}{\i A}= \\b \\lc\\|\\rc\\| ({ \\a \\ac \\co4 ({\i a}\\s\\do4({\fs15 11}),{\i a}\\s\\do4({\fs15 12}),{\u8943*},{\i a}\\s\\do4({\fs15 1{\i n}}),{\i a}\\s\\do4({\fs15 21}),{\i a}\\s\\do4({\fs15 22}),{\u8943*},{\i a}\\s\\do4({\fs15 2{\i n}}),{\u8942*},{\u8942*},{\u8945*},{\u8942*},{\i a}\\s\\do4({\fs15 {\i m}1}),{\i a}\\s\\do4({\fs15 {\i m}2}),{\u8943*},{\i a}\\s\\do4({\fs15 {\i m}{\i n}}))})}}{\fldrslt }}
} }}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 The {\b0\i0\scaps0\f3 array} environment is often used to typeset material that is not, strictly speaking, an array:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par f(x) = \\left\\\{ \\begin\{array\}\{ll\}
\par   x & \\mbox\{for $x<1$\}\\\\
\par x^2 & \\mbox\{for $x \\geq 1$\}  
\par \\end\{array\} \\right.
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which will yield\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\fs19 {{\field{\*\fldinst{ EQ {\i f}({\i x})= \\b \\lc\\\{ ({ \\a \\al \\co2 ({\i x},{for\~{{\i x}<1}},x\\s\\up4({\fs15 2}), {for\~{{\i x}{\u8805*}1}} )})}}{\fldrslt }}
} }}\par
\pard\plain\s4\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb180 \fi0 {\*\bkmkstart BMsec_mathspace}3.4.12{\*\bkmkend BMsec_mathspace}  Changes to spacing\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Sometimes {\plain L{\up6\fs19 A}T{\dn7 E}X} needs a little help in spacing an expression, or perhaps you think that the default spacing needs adjusting. For these purposes we have the following spacing commands:\par
{\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi0 \par
{\trowd\cellx1760\cellx4489\cellx4727\cellx6626\cellx9217
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\,}}\cell}
{\pard\intbl\ql {thin space}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\:}}\cell}
{\pard\intbl\ql {medium space}\cell}
\row}
{\trowd\cellx1760\cellx4489\cellx4727\cellx6626\cellx9217
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\!}}\cell}
{\pard\intbl\ql {negative thin space}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\;}}\cell}
{\pard\intbl\ql {thick space}\cell}
\row}
{\trowd\cellx1760\cellx4489\cellx4727\cellx6626\cellx9217
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\quad}}\cell}
{\pard\intbl\ql {a quad of space}\cell}
{\pard\intbl\ql {}\cell}
{\pard\intbl\ql {{\b0\i0\scaps0\f3 \\qquad}}\cell}
{\pard\intbl\ql {two quads of space}\cell}
\row}
}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi360 The spacing commands {\b0\i0\scaps0\f3 \\,}, {\b0\i0\scaps0\f3 \\quad}, and {\b0\i0\scaps0\f3 \\qquad} can be used in paragraphing mode, too. Here are some examples of these spacing commands used to make subtle modifications to some expressions.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 {\par
\fs19 {{\pard\plain\s9\qc\sb120\sa120\keep\widctlpar\f0\sl240\slmult1 \sb120 \fi0 \fs19 \par
{\trowd\cellx4999\cellx9219
{\pard\intbl\ql {\scaps0\b0\i {Type}}\cell}
{\pard\intbl\ql {\scaps0\b0\i To produce}\cell}
\row}
{\trowd\cellx4999\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\sqrt\{2\} \\, x$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\R(,2){\charscalex50\~}{\i x}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4999\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\int_a^b f(x)\\,dx$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\i ({\i a},{\i b}, ){\i f}({\i x}){\charscalex50\~}{\i d}{\i x}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4999\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\Gamma_\{\\!2\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ {\u915*}\\s\\do4({\fs15 2})}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4999\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\int_a^b \\! \\int_c^d f(x,y)\\,dx\\,dy$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\i ({\i a},{\i b}, ) \\i ({\i c},{\i d}, ){\i f}({\i x}\\,{\i y}){\charscalex50\~}{\i d}{\i x}{\charscalex50\~}{\i d}{\i y}}}{\fldrslt }}
}}\cell}
\row}
{\trowd\cellx4999\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $x / \\! \\sin x$}}\cell}
{\pard\intbl\ql {{{\i x}/{\plain sin}{\i x}}}\cell}
\row}
{\trowd\cellx4999\cellx9219
{\pard\intbl\ql {{\b0\i0\scaps0\f3 $\\sqrt\{\\,\\sin x\}$}}\cell}
{\pard\intbl\ql {{{\field{\*\fldinst{ EQ  \\R(,{\charscalex50\~}{\plain sin}{\i x})}}{\fldrslt }}
}}\cell}
\row}
}\par
}}\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb360 \fi0 3.5  Alignment\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Recall that the {\b0\i0\scaps0\f3 $equation$} environment can be used to display and automatically number a single- line equation{\cs62\super\chftn}
{\*\footnote\pard \s65\ql\fi-113\li397\lin397\f0\fs24{\cs62\super\chftn} See section {\field{\*\fldinst{\lang1024 REF BMsec_display \\* MERGEFORMAT }}{\fldrslt{3.2}}}}
. The {\b0\i0\scaps0\f3 eqnarray} environment is used for displaying and automatically numbering either a single expression that spreads over several lines or multiple expressions, while taking care of alignment for us. The syntax is similar to that of the {\b0\i0\scaps0\f3 tabular} and {\b0\i0\scaps0\f3 array} environments, except that no argument is necessary to declare the number and justification of columns. The {\b0\i0\scaps0\f3 eqnarray*} environment does this without numbering any equations.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{eqnarray\}
\par (a+b)(a+b) & = & a^2 + 2ab + b^2\\\\
\par (a+b)(a-b) & = & a^2 - b^2
\par \\end\{eqnarray\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 will give\par
{\pard\plain\s16\ql\sb120\sa120\keep\widctlpar\f0\tqr\tx4149\tqc\tx4610\tql\tx5071\tqr\tx9220\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ ({\i a}+{\i b})({\i a}+{\i b})}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ =}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ {\i a}\\s\\up6({\fs20 2})+2{\i a}{\i b}+{\i b}\\s\\up6({\fs20 2})}}{\fldrslt }}
\tab{\b0 (1)}\par
\pard\plain\s16\ql\sb120\sa120\keep\widctlpar\f0\tqr\tx4149\tqc\tx4610\tql\tx5071\tqr\tx9220\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ ({\i a}+{\i b})({\i a}\u8722?{\i b})}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ =}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ {\i a}\\s\\up6({\fs20 2})\u8722?{\i b}\\s\\up6({\fs20 2})}}{\fldrslt }}
\tab{\b0 (3.2)}\par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 See how we identify the columns so as to line the {=} signs up. We can also leave entries empty, to obtain effect like the following:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{eqnarray*\}
\par \\frac\{d\}\{dx\} \\sin x & = & \\lim_\{h\\rightarrow0\}\\frac\{\\sin(x+h)-\\sin x\}\{h\}\\\\
\par & = & \\lim_\{h\\rightarrow0\}\\frac\{\\sin x\\cos h + \\cos x\\sinh - \\sin x\}\{h\}\\\\ 
\par & = & \\lim_\{h\\rightarrow0\}\\frac\{\\sin x(\\cos h-1)\}\{h\} + \\cos x\\frac\{\\sin h\}\{h\}\\\\
\par & = & \\cos x
\par \\end\{eqnarray*\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which produces\par
{\pard\plain\s15\ql\sb120\sa120\keep\widctlpar\f0\tqr\tx4149\tqc\tx4610\tql\tx5071\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ  \\F({\i d},{\i d}{\i x}){\plain sin}{\i x}}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ =}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ \\a\\ac(lim,{\i h}{\u8594*}0) \\F({\plain sin}({\i x}+{\i h})\u8722?{\plain sin}{\i x},{\i h})}}{\fldrslt }}
\par
\pard\plain\s15\ql\sb120\sa120\keep\widctlpar\f0\tqr\tx4149\tqc\tx4610\tql\tx5071\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ }}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ =}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ \\a\\ac(lim,{\i h}{\u8594*}0) \\F({\plain sin}{\i x}{\plain cos}{\i h}+{\plain cos}{\i x}{\plain sinh}\u8722?{\plain sin}{\i x},{\i h})}}{\fldrslt }}
\par
\pard\plain\s15\ql\sb120\sa120\keep\widctlpar\f0\tqr\tx4149\tqc\tx4610\tql\tx5071\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ }}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ =}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ \\a\\ac(lim,{\i h}{\u8594*}0) \\b \\bc\\\{ ( \\F({\plain sin}{\i x}({\plain cos}{\i h}\u8722?1),{\i h})+{\plain cos}{\i x} \\F({\plain sin}{\i h},{\i h}))}}{\fldrslt }}
\par
\pard\plain\s15\ql\sb120\sa120\keep\widctlpar\f0\tqr\tx4149\tqc\tx4610\tql\tx5071\sl240\slmult1 \fi0 \tab
{\field{\*\fldinst{ EQ }}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ =}}{\fldrslt }}
\tab
{\field{\*\fldinst{ EQ {\plain cos}{\i x}}}{\fldrslt }}
\par
}\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 3.6  Theorems, Propositions, Lemmas, {\u8230?}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Suppose you document contains four kinds of theorem-like structures: \ldblquote theorems\rdblquote , \ldblquote propositions\rdblquote , \ldblquote conjectures\rdblquote , and \ldblquote wild guesses\rdblquote . Then near the beginning of the document you should have something like the following:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19  
\par \\newtheorem\{thm\}\{Theorem\}
\par \\newtheorem\{prop\}\{Proposition\}
\par \\newtheorm\{conjec\}\{Conjecture\}
\par \\newtheorem\{wildshot\}\{Hypothesis\} % make it sound good!
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 The first argument to {\b0\i0\scaps0\f3 \\newtheorem} defines a new theorem-like environment name of your own choosing. The second argument contains the text that you want inserted when your theorem is proclaimed:\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\begin\{thm\} $X$ is normal if, and only if, each pair of disjoint
\par closed sets in $X$ is completely separated.
\par \\end\{thm\}
\par 
\par \\begin\{wildshot\} % remember, we chose the name 'wildshot'
\par The property of Moore extends to all objects of the class $\\Sigma$.
\par \\end\{wildshot\}
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 which will produce the following:\par
{\pard\plain\s17\ql\sb120\sa120\keep\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 {\b Theorem 1} {\i {{\i X}} is normal if, and only if, each pair of disjoint closed sets in {{\i X}} is completely separated. }\par
}{\pard\plain\s17\ql\sb120\sa120\keep\widctlpar\f0\fs24\sl240\slmult1 \sb120 \fi0 {\b Hypothesis 1} {\i The property of Moore extends to all objects of the class {{\u931*}}. }\par
}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi360 Notice that {\plain L{\up6\fs19 A}T{\dn7 E}X} italicises the theorem statement, and that you still have to shift in to maths mode when you want to set symbols and expression. Typically, it is the style file that determines what a theorem will appear like\emdash so don\rquote t go changing this if you are preparing for submission for publication (because the journal staff want to substitute their production style for your document style choice, and not be over-ridden by other commands).\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 3.7  Where to from here?\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 We have covered a good deal of {\plain L{\up6\fs19 A}T{\dn7 E}X}\rquote s mathematical abilities, albeit rather superficial coverage here and there. There is much that has been impressive, but there is clearly a lot more to {{\plain T{\dn7 E}X}}nical typesetting than we have covered here\emdash it is not difficult to think of an expression that we don\rquote t yet know how to typeset. Also, there are places where {\plain L{\up6\fs19 A}T{\dn7 E}X} is a little weak and it leaves us to do somewhat more work than the spirit of {\plain T{\dn7 E}X} would suggest.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Of course, we cannot criticise {\plain L{\up6\fs19 A}T{\dn7 E}X} until we know its full capability. So the first place to go from here is the {\i {\plain L{\up6\fs19 A}T{\dn7 E}X} User\rquote s Guide & Reference Manual}. Particularly, the command reference guide in Appendix C of that book is an invaluable source of {\plain L{\up6\fs19 A}T{\dn7 E}X} information that few can afford to do without. With good knowledge of the {\plain L{\up6\fs19 A}T{\dn7 E}X} environments and their options (and we\rquote ve left out many here) one can accomplish a good deal of most typesetting problems. A little imagination (say putting an environment to a slightly non-standard use) can often solve more difficult problems. Lastly, of course, much of raw {\plain T{\dn7 E}X} still sits underneath {\plain L{\up6\fs19 A}T{\dn7 E}X} and so it is true to say that you can do {\i anything} with {\plain L{\up6\fs19 A}T{\dn7 E}X}\emdash but you may need some divine inspiration from time to time (ask your local {\plain T{\dn7 E}X} guru).\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 In the next chapter we will look, very briefly, at a number of {\plain L{\up6\fs19 A}T{\dn7 E}X} commands that we have not yet considered. Nothing exciting on the mathematical front, but there is some other important material (e.g. cross-referencing and page-sizing). For now, let\rquote s look at the \ldblquote way forward\rdblquote  with respect to mathematical typesetting.\par
\pard\plain\s3\ql\sb240\sa120\keepn\f0\b\fs32\sl240\slmult1 \sb240 \fi0 3.8  {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X}\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 Back in the introduction we said that {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} was just a big macro package, the result of a marriage of {\plain L{\up6\fs19 A}T{\dn7 E}X} and {\plain {\i AmS}-T{\dn7 E}X} designed to endow the powerful general-purpose {\plain L{\up6\fs19 A}T{\dn7 E}X} package with the mathematical prowess of {\plain {\i AmS}-T{\dn7 E}X} without compromising the {\plain L{\up6\fs19 A}T{\dn7 E}X} syntax. Most of that is true, except that {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} is really just a document-style option (like {\b0\i0\scaps0\f3 12pt}) that can be used within a \ldblquote tweaked {\plain L{\up6\fs19 A}T{\dn7 E}X}\rdblquote . The most visible part of this tweak is the {\i new font selection scheme of Mittelbach and Sch\'f6pf}, discussed more fully in the next chapter. Almost every {\plain L{\up6\fs19 A}T{\dn7 E}X} command and environment survived the transition to {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X}, the exceptions being those that were considered redundant or under-used (space is at a premium with such a big package). The tweaked {\plain L{\up6\fs19 A}T{\dn7 E}X} package is therefore able to deal with practically every existing {\plain L{\up6\fs19 A}T{\dn7 E}X} document, giving just a few (often pleasant) surprises.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 With the {\b0\i0\scaps0\f3 amstex} style option, one can just start a {\plain L{\up6\fs19 A}T{\dn7 E}X} document with\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 { \fs19 {\par
\pard\plain\s38\ql\widctlpar\f3\fs24\sl240\slmult1 \fi0 \fs19 
\par \\documentstyle[amstex]\{article\} % or report, book, etc
\par \par
}}\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \sb60 \fi0 to gain access to the {{\plain T{\dn7 E}X}}nical excellence of the AMS technical staff. It is not necessary to have read {\i The Joy of {\plain T{\dn7 E}X}} (the {\plain {\i AmS}-T{\dn7 E}X} reference guide) to be able to use the {\b0\i0\scaps0\f3 amstex} option, for {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} comes with its own reference guide. Even so, {\i The Joy of TeX} is still highly recommended reading. The syntax of {\plain {\i AmS}-T{\dn7 E}X} has been changed to that of {\plain L{\up6\fs19 A}T{\dn7 E}X}, but one can perform that transformation as you read \ldblquote {\i Joy}\rdblquote  and still learn much of the art of technical typesetting. Nowhere else will you find so comprehensive a coverage of the conventions and pitfalls of mathematical typesetting. In addition, {\i Joy} lists all the extra symbols that are available through the {\b0\i0\scaps0\f3 amstex} option (if you thought {\plain L{\up6\fs19 A}T{\dn7 E}X} had a fair selection of esoteric symbols, just wait \rquote til you see those!) and provides in-depth accounts where the {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} documentation is brief.\par
\pard\plain\s0\qj\widctlpar\f0\fs24\sl240\slmult1 \fi360 Just as {\plain {\i AmS}-T{\dn7 E}X} comes with the AMS preprint style ({\b0\i0\scaps0\f3 amsppt}), {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} comes with a specialist style file for preparation of articles with {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} for submission to journals: {\b0\i0\scaps0\f3 amsart}. The {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X} User\rquote s Guide is quite short and very terse in its explanations (assuming you to be competent in {\plain L{\up6\fs19 A}T{\dn7 E}X}), but is supplemented by a large body of examples and a comprehensive sample article that is a showcase of the abilities of the {\b0\i0\scaps0\f3 amsart} style. You must read both these documents to really learn {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X}. The AMS also distributes a guide to authors who wish to submit using {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X}, and this is a must-read once you are familiar with some of {\plain {\i AmS}-L{\up6\fs19 A}T{\dn7 E}X}. \par
}}
}}}