isomath
*******
Mathematical style for science and technology
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

:Date:      2012-09-10
:Copyright: © 2008, 2012 Günter Milde
:Licence:   This work may be distributed and/or modified under the
            conditions of the `LaTeX Project Public License`_, either
            version 1.3 of this license or (at your option) any later version.

:Abstract: The `isomath` package provides tools for a mathematical style
           that conforms to the International Standard ISO 80000-2 and is
           common in science and technology. It changes the default shape of
           capital Greek letters to italic, sets up bold italic and
           sans-serif bold italic math alphabets with Latin and Greek
           characters, and defines macros for markup of vector, matrix and
           tensor symbols.

:Identification:
 ::

  \NeedsTeXFormat{LaTeX2e}
  \ProvidesPackage{isomath}
  [2012/09/04 v0.6.1 ISO math style]
  
.. contents::

History
=======

.. class:: borderless

===== ===========  ========================================================
0.1   2008-09-25   first public version.
0.2   2008-10-02   bugfix: a usage example was uncommented;
\                  updated documentation;
\                  define \mathsans only if OMLmathsans is true;
\                  option reuseMathalphabets -> reuseMathAlphabets.
0.3   2009-06-19   documentation update;
\                  fix OMLmathrm and OMLmathsans definitions;
\                  switch license to LPP.
0.4   2010-08-23   split user documentation from literate source;
\                  option ``scaled``;
\                  documentation update.
0.5   2011-01-04   math alphabet names matching Unicode;
\                  documentation review and extension;
\                  bold alphabet variants in ``bold`` math version;
\                  upright numbers with ``\vectorsym``.
0.6   2012-09-10   Scaling for Kepler Sans (``sfdefault=jkpss``);
\                  documentation update, new caption and abstract.
===== ===========  ========================================================


Requirements
============

fixmath.sty
-----------
The package fixmath_ by Walter Schmidt defines Greek letters as symbols
of type ``\mathalpha`` and takes them from the ``letters`` symbol font in
``\mathnormal`` (as opposed to ``operators`` in ``fontmath.ltx``).

`fixmath` also defines the ``\mathbold`` alphabet, setting it to ``cmm``.
`isomath` overwrites this definition with a configurable value for
the font family. ::

  \RequirePackage{fixmath}
  
  
kvoptions.sty
-------------
The kvoptions_ package in the oberdiek_ bundle facilitates the setup of
package options and provides a key=value interface (based on keyval_)::

  \RequirePackage{kvoptions}
  
  
Options
=======

rmdefault
---------
Family for roman math fonts. Must be available in OML
encoding. The default is to use the corresponding text font family
(``\rmdefault``). ::

  \DeclareStringOption[\rmdefault]{rmdefault}
  
sfdefault
---------
Family for sans-serif math fonts. The default selects `CM Bright`, as
most sans serif fonts are not available in OML encoding::

  \DeclareStringOption[cmbr]{sfdefault}
  
scaled
------
The sans-serif fonts, ``fav`` (Arev), ``llcmss`` (LX Fonts), 
``jkpss`` (Kepler Serif) and ``iwona`` can be scaled 
with the ``scaled`` option. ::

  \DeclareStringOption[1.0]{scaled}
  
reuseMathAlphabets
------------------
The definition of new `math alphabets`_ can lead to a “too many math
alphabets used in version normal” error.

As a workaround, this option tells `isomath` to re-use the existing
``\mathbf`` and ``\mathsf`` alphabets for *italic* bold and sans-serif
bold. ::

  \DeclareBoolOption{reuseMathAlphabets}
  
OMLmath*
--------
The following options cause `isomath` to (re)define the corresponding
`math alphabets`_ in OML encoding::

  \DeclareBoolOption{OMLmathrm}
  \DeclareBoolOption{OMLmathbf}
  \DeclareBoolOption{OMLmathsf}
  \DeclareBoolOption{OMLmathsfit}
  \DeclareBoolOption{OMLmathtt}
  % backwards compatibility option alias
  \DeclareVoidOption{OMLmathsans}{\isomath@OMLmathsfittrue}
  
Setting these options enables access to small Greek letters in different
shapes with e.g. ``\mathrm{\pi}`` but only *if an OML encoded font is
available*. Currently, only the mathdesign_ fonts support roman in OML
encoding.

With some packages, these options can result in a “too many math alphabets
used in version normal” error.

--------------------------------------------------------

Process the options with ``kvoptions`` extensions::

  \ProcessKeyvalOptions*
  
  
Declarations
============

Math alphabets
--------------

In math, LaTeX uses “absolute” fontnames instead of a selection by
family, shape, and weight because typefaces have a semantic meaning
[fntguide]_.

`isomath` defines a math alphabet for every required font variant and
optionally re-defines the standard math alphabets in `OML` font encoding.

Unfortunately, the number of math alphabets in one math version is
limited to 16, so we have to be careful not to exceed this. The
``reuseMathAlphabets`` option reduces the number of math alphabet
definitions by two, with the side effect of italic shape with
``\mathbf`` and ``\mathsf`` commands::

  \ifisomath@reuseMathAlphabets
    \PackageWarningNoLine{isomath}{%
      Re-using math alphabet `mathsf' for \protect \mathsfbfit
      \MessageBreak and `mathbf' for \protect \mathbfit
    }
  \fi
  
mathbfit
~~~~~~~~
The *bold italic* math alphabet is named ``\mathbfit`` like in
unicode-math_ (with an alias ``\mathbold`` like in fixmath_ and
related packages). With the reuseMathAlphabets_ option, the roman bold
math alphabet ``\mathbf`` is redefined and ``\mathbfit`` made an
alias. The series selector ``bx`` (bold extended) is used, because it
is better supported than ``b``. (Is there any LaTeX math font
distinguishing between ``b`` and ``bx``?) ::

  \ifisomath@reuseMathAlphabets
    \DeclareMathAlphabet{\mathbf}{OML}{\isomath@rmdefault}{bx}{it}
    \def\mathbfit{\mathbf}
  \else
    \DeclareMathAlphabet{\mathbfit}{OML}{\isomath@rmdefault}{bx}{it}
  \fi
  
alias (overwriting the definition from fixmath)::

  \renewcommand*{\mathbold}{\mathbfit}
  
mathsfit
~~~~~~~~
For *sans-serif italic*, we define a new alphabet ``\mathsfit`` (with
the alias ``\mathsans`` in analogy to ``\mathbold``). As this typeface
is not required by ISO 80000-2 and TeX limits the number of math alphabets
to 16 per math version, it is only defined if the ``OMLmathsfit`` or
``OMLmathsans`` option is set::

  \ifisomath@OMLmathsfit
    \DeclareMathAlphabet{\mathsfit}{OML}{\isomath@sfdefault}{m}{it}
    \SetMathAlphabet{\mathsfit}{bold}{OML}{\isomath@sfdefault}{bx}{it}
    \def\mathsans{\mathsfit}
  \fi
  
mathsfbfit
~~~~~~~~~~~~
The *sans serif bold italic* alphabet is used for tensor symbols.
Following the Unicode naming scheme it is called
``\mathsfbfit``(with the backwards compatibility alias ``\mathboldsans``).
With the reuseMathAlphabets_ option, the upright sans serif math
alphabet ``\mathsf`` is redefined and ``\mathsfbfit`` made an
alias to it::

  \ifisomath@reuseMathAlphabets
    \DeclareMathAlphabet{\mathsf}{OML}{\isomath@sfdefault}{bx}{it}
    \def\mathsfbfit{\mathsf}
  \else
    \DeclareMathAlphabet{\mathsfbfit}{OML}{\isomath@sfdefault}{bx}{it}
  \fi
  \def\mathboldsans{\mathsfbfit}
  
Redefine standard alphabets
~~~~~~~~~~~~~~~~~~~~~~~~~~~

Redefine standard alphabets in `OML` font encoding
if the corresponding `OMLmath*`_ option is true::

  \ifisomath@OMLmathrm
    \SetMathAlphabet{\mathrm}{normal}{OML}{\isomath@rmdefault}{m}{n}
    \SetMathAlphabet{\mathrm}{bold}{OML}{\isomath@rmdefault}{bx}{n}
  \fi
  \ifisomath@OMLmathbf
    \SetMathAlphabet{\mathbf}{normal}{OML}{\isomath@rmdefault}{bx}{n}
  \fi
  \ifisomath@OMLmathsf
    \SetMathAlphabet{\mathsf}{normal}{OML}{\isomath@sfdefault}{m}{n}
    \SetMathAlphabet{\mathsf}{bold}{OML}{\isomath@sfdefault}{bx}{n}
  \fi
  \ifisomath@OMLmathtt
    \SetMathAlphabet{\mathtt}{normal}{OML}{\ttdefault}{m}{n}
    \SetMathAlphabet{\mathtt}{bold}{OML}{\ttdefault}{bx}{n}
  \fi
  
Command aliases
---------------

The following macros allow semantic markup of mathematical symbols.
The argument is typeset as proposed by ISO 80000-2 and
`Typefaces for Symbols in Scientific Manuscripts`_.

\\vectorsym
~~~~~~~~~~~
Alphabetic vectors symbols are typeset *boldface italic* while numeric
ones (e.g. zero vector) are typeset *boldface upright*. The number
test is a simplified version from the LaTeX FAQ "`Is the argument a number?`__"
It fails if a number is followed by a non-number, e.g. ``\vectorsym{1a}``,
but this is no valid vector symbol and would look strange with the
``\vec`` accent, too. ::

  \providecommand*{\vectorsym}[1]{%
    \ifnum9<1#1%
      \mathbf{#1}%
    \else%
      \mathbfit{#1}%
    \fi}
  
For easier writing or to make existing documents conform to the standard,
you might want to re-define the standard ``\vec`` command after loading this
package.

__ http://www.tex.ac.uk/cgi-bin/texfaq2html?label=isitanum

\\matrixsym
~~~~~~~~~~~
Symbols for matrices are typeset *boldface italic*, i. e. in the same face
as vectors. ::

  \providecommand*{\matrixsym}{\vectorsym}
  
\\tensorsym
~~~~~~~~~~~
Symbols for tensors are *sans-serif bold italic*::

  \providecommand*{\tensorsym}{\mathsfbfit}
  
  
Font setup fixes
----------------

Substitutions needed for the math alphabet definitions and setup for
scaled fonts. For details about the font definition macros see
[fntguide]_.

Unknown makro in font definition file
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The `Kepler Sans` font definition file ``omljkpss.fd`` contains a boolean
that is defined in ``kpfonts.sty``. This leads to errors if the fonts are
used from another package. Provide a dummy definition::

  \newif\ifkp@upRm
  
  
Common family name for text and math fonts
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Some font packages provide matching text and math font but do not
define a substitution in their ``*.fd`` files. Ideally, the following
mappings should be moved there.

Mathpazo (Palatino) ppl ↔ zplm ::

  \DeclareFontFamily{OML}{ppl}{\skewchar\font127}
  \DeclareFontShape{OML}{ppl}{m}{it}{<-> ssub * zplm/m/it}{}
  \DeclareFontShape{OML}{ppl}{bx}{it}{<-> ssub * zplm/b/it}{}
  
  
Scaling
~~~~~~~
Scale the ``fav`` (Arev), ``iwona``, ``jkpss`` (Kepler Sans) and
``llcmss`` (LX Fonts) sans serif fonts by the value of the scaled_ option.

To get scaled versions of a font, you cannot use the ``ssub``
`size function`, but must use the empty function or ``s`` with the font
file as argument [found by experiment, GM 2010-01-28].

Arev (see ``omlzavm.fd``) fav ↔ zavm::

  \DeclareFontFamily{OML}{fav}{\skewchar\font127}
  \DeclareFontShape{OML}{fav}{m}{it}{<-> s * [\isomath@scaled] zavmri7m}{}
  \DeclareFontShape{OML}{fav}{bx}{it}{<-> s * [\isomath@scaled] zavmbi7m}{}
  
Iwona (see ``omliwona.fd``) iwona ↔ mi-iwona::

  \DeclareFontFamily{OML}{iwona}{}
  \DeclareFontShape{OML}{iwona}{m}{it}{<-> s * [\isomath@scaled] mi-iwonari}{}
  \DeclareFontShape{OML}{iwona}{bx}{it}{<-> s * [\isomath@scaled] mi-iwonabi}{}
  
Kepler Serif (see ``omljkpss.fd``)::

  \DeclareFontFamily{OML}{jkpss}{\skewchar\font127 }
  \DeclareFontShape{OML}{jkpss}{m}{it}{<-> s * [\isomath@scaled] jkpssmi}{}
  \DeclareFontShape{OML}{jkpss}{bx}{it}{<-> s * [\isomath@scaled] jkpssbmi}{}
  
LX Fonts (see ``lxfonts.sty``) llcmss ↔ llcmm::

  \DeclareFontFamily{OML}{llcmss}{\skewchar\font'177}
  \DeclareFontShape{OML}{llcmss}{m}{it}{<-> s * [\isomath@scaled] lcmmi8}{}
  \DeclareFontShape{OML}{llcmss}{bx}{it}{<-> s * [\isomath@scaled] lcmmib8}{}
  
  
References
==========

.. [fntguide] `LaTeX 2e font selection`:
   http://mirror.ctan.org/macros/latex/doc/fntguide.pdf.

.. _LaTeX Project Public License: http://www.latex-project.org/lppl.txt
.. _arev: http://mirror.ctan.org/help/Catalogue/entries/arev.html
.. _cmbright: http://mirror.ctan.org/help/Catalogue/entries/cmbright.html
.. _fixmath: http://mirror.ctan.org/help/Catalogue/entries/fixmath.html
.. _hvmath: http://mirror.ctan.org/help/Catalogue/entries/hvmath.html
.. _iwona: http://mirror.ctan.org/help/Catalogue/entries/iwona.html
.. _keyval: http://mirror.ctan.org/help/Catalogue/entries/keyval.html
.. _kvoptions: http://mirror.ctan.org/help/Catalogue/entries/kvoptions.html
.. _lxfonts: http://mirror.ctan.org/help/Catalogue/entries/lxfonts.html
.. _mathdesign: http://mirror.ctan.org/help/Catalogue/entries/mathdesign.html
.. _mathematical alphanumeric symbols:
    http://www.unicode.org/charts/PDF/U1D400.pdf
.. _oberdiek: http://mirror.ctan.org/help/Catalogue/entries/oberdiek.html
.. _`Typefaces for Symbols in Scientific Manuscripts`:
   http://physics.nist.gov/cuu/pdf/typefaces.pdf
.. _unicode-math:
   http://mirror.ctan.org/help/Catalogue/entries/unicode-math.html