.TH STYLE 1 "@UPDATED@" "GNU" "User commands"
.SH NAME \"{{{roff}}}\"{{{
style \- analyse surface characteristics of a document
.\"}}}
.SH SYNOPSIS \"{{{
.\" Missing options:
.\" -a    displays all sentences with their length and readability index.
.\" -e    displays all sentences that begin with an expletive.
.\" -P    displays parts of speech of the words in the document.
.\" -p    displays all sentences that contain a passive verb.
.ad l
.B style
.RB [ \-L
.IR language ]
.RB [ \-l
.IR length ]
.RB [ \-r
.IR ari ]
.RI [ file ...]
.ad b
.br
.ad l
.B style
.RB [ \-\-language
.IR language ]
.RB [ \-\-print-long
.IR length ]
.RB [ \-\-print-ari
.IR ari ]
.RI [ file ...]
.ad b
.br
.ad l
.B style
.BR \-h | \-\-help 
.ad b
.br  
.ad l
.B style \-\-version
.ad b
.\"}}}
.SH DESCRIPTION \"{{{
\fBStyle\fP analyses the surface characteristics of the writing style
of a document.  It prints various readability grades, length of words,
sentences and paragraphs.
.\" sentence structure, word usage, verb type, sentence openers
It can further locate sentences with certain characteristics.
If no files are given, the document is read from standard input.
.PP
Numbers are counted as words with one syllable.
A sentence is a sequence of words, that starts with a capitalised word and
ends with a full stop, double colon, question mark or exclamation mark.
A single letter followed by a dot is considered an abbreviation, so it
does not end a sentence.  Various multi-letter abbreviations are
recognized, they do not end a sentence as well.
A paragraph
consists of two or more new line characters.
.SS "Readability grades"
\fBStyle\fP understands \fIcpp\fP(1) \fB#line\fP lines for being able to
give precise locations when printing sentences.
.IP "Kincaid formula" \"{{{ 
The Kincaid Formula was developed for U.S. Navy training manuals; it
ranges in difficulty from 5.5 to 16.3.  It is probably best applied to
technical documents, because it is based on adult training manuals
rather than school book text.  Dialogs (often found in fictional
texts) are usually a series of short sentences, which lowers the
score.  On the other hand, scientific texts with many long scientific
terms are rated higher, although they are not necessarily harder to
read for people who are familiar with those terms.
.sp
.\"{{{ Kincaid Index
.if t \{\
.RS
.EQ
italic "Kincaid" = 11.8 * syllables over words + 0.39 * words over sentences - 15.59
.EN
.RE
.\}
.if n \{\
.ad l
Kincaid = 11.8*syllables/wds+0.39*wds/sentences-15.59
.ad b
.\}
.\"}}}
.\"}}}
.IP "Automated Readability Index" \"{{{ 
The Automated Readability Index is typically higher than Kincaid and
Coleman-Liau, but lower than Flesch.
.sp
.\"{{{ Automated Readability Index
.if t \{\
.RS
.EQ
italic "ARI" = 4.71 * letters over words + 0.5 * words over sentences - 21.43
.EN
.RE
.\}
.if n \{\
.ad l
ARI = 4.71*chars/wds+0.5*wds/sentences-21.43
.ad b
.\}
.\"}}}
.\"}}}
.IP "Coleman-Liau Formula" \"{{{ 
The Coleman-Liau Formula usually gives a lower grade than Kincaid,
ARI and Flesch when applied to technical documents.
.sp
.\"{{{ Coleman-Liau Formula
.if t \{\
.RS
.EQ
italic "Coleman-Liau" = 5.88 * letters over words - { 29.5 * sentences } over words - 15.8
.EN
.RE
.\}
.if n \{\
.ad l
Coleman-Liau = 5.88*chars/wds-29.5*sent/wds-15.8
.ad b
.\}
.\"}}}
.\"}}}
.IP "Flesch Reading Ease formula" \"{{{ 
Developed by Rudolph Flesch in 1948, the Flesch Reading Ease formula
is based on school texts covering grades 3 to 12.  It is widespread,
especially in the USA, because it is computed easily and produces good
results.  The index ranges from 0 (hard) to 100 (easy).  Standard
English documents average around 60 to 70.  Applying it to German
documents gives bad results because of the different language
structure.
.sp
.\"{{{ Flesh reading easy formula
.if t \{\
.RS
.EQ
Flesch ~ Index = 206.835 - 84.6 * syllables over words - 1.015 * words over sentences
.EN
.RE
.\}
.if n \{\
.ad l
Flesch Index = 206.835-84.6*syll/wds-1.015*wds/sent
.ad b
.\}
.\"}}}
.\"}}}
.IP "Fog Index" \"{{{
The Fog index was developed by Robert Gunning.  Its value is a school
grade.  The \(lqideal\(rq Fog Index level is 7 or 8.  A level above 12
indicates the writing sample is too hard for most people to read.
Texts less than 100 words will not produce meaningful results.  Note
that a correct implementation would not count words of three or more
syllables that are proper names, combinations of easy words, or made
three syllables by suffixes such as \(ened, \(enes, or \(ening.
.sp
.\"{{{ Fog Index formula
.if t \{\
.RS
.EQ
Fog ~ Index = 0.4 * left ( words over sentences + 100 * { { words >= 3 ~ syllables } over words } right )
.EN
.RE
.\}
.if n \{\
.ad l
Fog Index = 0.4*(wds/sent+100*((wds >= 3 syll)/wds))
.ad b
.\}
.\"}}}
.\"}}}
.\" might be wrong
.\".IP "WSFT Index" \"{{{
.\"The first new Vienna text formula (1. neue Wiener Sachtextformel, WSTF)
.\"has been developed for German documents and its result is a school grade
.\"that could read the text.
.\".sp
.\"{{{ WSTF
.\".if t \{\
.\".RS
.\".EQ
.\"matrix {
.\"col { WSTF ~ Index = above ~ }
.\"lcol {
.\"0.1935 * { words >= 3 ~ syllables } over words + 0.1672 * words over sentences -
.\"above 
.\"down 70 { 0.1297 * { words > 6 ~ characters } over words - 0.0327 * { words = 1 ~ syllable } over words - 0.875 }
.\"}
.\"}
.\".EN
.\".RE
.\".\}
.\".if n \{\
.\".ad l
.\"WSTF Index =  0.1935*(wds >= 3 syllables)/wds
.\"             +0.1672*wds/sent
.\"             -0.1297*(wds > 6 characters)/wds
.\"             -0.0327*(wds = 1 syllable)/wds
.\"             -0.875
.\".ad b
.\".\}
.\"}}}
.\"}}}
.\" might be wrong
.\".IP "Wheeler-Smith Index" \"{{{ 
.\"The Wheeler-Smith Index is mapped to school grades using a table:
.\".sp
.\"{{{ Wheeler-Smith Index
.\".if t \{\
.\".RS
.\".EQ
.\"italic "Wheeler-Smith" ~ Index =
.\"words over sentences * 100 * { words >= 3 ~ syllables } over words
.\".EN
.\".RE
.\".\}
.\".if n \{\
.\".ad l
.\"Wheeler-Smith Index = wds/sent*100*((wds >= 3 syll)/wds)
.\".ad b
.\".\}
.\"}}}
.\".sp
.\".RS
.\".TS
.\"tab(#);
.\"l c c c c c c c c c c c c c.
.\"Index#16##20##24##29##34##38##42
.\"School year##5##6##7##8##9##10
.\".TE
.\".RE
.\"}}}
.IP "Lix formula" \"{{{
The Lix formula developed by Bj\(:ornsson from Sweden is very simple and
employs a mapping table as well:
.sp
.\"{{{ Lix
.if t \{\
.RS
.EQ
Lix =
words over sentences + 100 * { words > 6 ~ characters } over words
.EN
.RE
.\}
.if n \{\
.ad l
Lix = wds/sent+100*(wds >= 6 char)/wds
.ad b
.\}
.\"}}}
.sp
.RS
.ne 2
.TS
tab(#);
l c1 c1 c1 c1 c1 c1 c1 c1 c1 c1 c1 c1 c1 c1 c.
Index#34##38##41##44##48##51##54##57
School year##5##6##7##8##9##10##11
.TE
.RE
.\"}}}
.IP "SMOG Grading" \"{{{
The SMOG Grading for English texts was developed by McLaughlin in
1969.  Its result is a school grade.
.sp
.\"{{{ SMOG
.if t \{\
.RS
.EQ
italic "SMOG-Grading" = sqrt { { (words >= 3 ~ syllables) } over sentences * 30 } + 3
.EN
.RE
.\}
.if n \{\
.ad l
SMOG Grading = square root of (((wds >= 3 syll)/sent)*30) + 3
.ad b
.\}
.\"}}}
.sp
It was adapted to German by Bamberger and Vanecek in 1984, who changed
the constant +3 to \-2.
.\"}}}
.SS "Word usage"
The word usage counts are intended to help identify excessive use of particular
parts of speech.
.IP "Verb Phrases" \"{{{
The category of verbs labeled "to be" identifies phrases using the passive
voice.  Use the passive voice sparingly, in favor of more direct verb forms.
The flag \fB-p\fP causes \fBstyle\fP to list all occurrences of the passive
voice.
.PP
The verb category "aux" measures the use of modal auxiliary verbs, such as
"can", "could", and "should".  Modal auxiliary verbs modify the mood of a verb.
.\"}}}
.IP "Conjunctions" \"{{{
The conjunctions counted by style are coordinating and subordinating.
Coordinating conjunctions join grammatically equal sentence fragments, such as
a noun with a noun, a phrase with a phrase, or a clause to a clause.
Coordinating conjunctions are "and," "but," "or," "yet," and "nor."
.PP
Subordinating conjunctions connect clauses of unequal status.  A subordinating
conjunction links a subordinate clause, which is unable to stand alone, to an
independent clause.  Examples of subordinating conjunctions are "because,"
"although," and "even if."
.\"}}}
.IP "Pronouns" \"{{{
Pronouns are contextual references to nouns and noun phrases.  Documents with
few pronouns generally lack cohesiveness and fluidity.  Too many pronouns may
indicate ambiguity.
.\"}}}
.IP "Nominalizations" \"{{{
Nominalizations are verbs that are changed to nouns.  Style recognizes words
that end in "ment," "ance," "ence," or "ion" as nominalizations.
Examples are "endowment," "admittance," and "nominalization."  Too much
nominalization in a document can sound abstract and be difficult to understand.
The flag \fB-N\fP causes \fBstyle\fP to list all nominalizations.  The
flag \fB-n\fP prints all sentences with either the passive voice or a
nominalization.
.\"}}}
.\"}}}
.SH OPTIONS \"{{{
.IP "\fB\-L\fP \fIlanguage\fP, \fB\-\-language\fP \fIlanguage\fP"
set the document language (\fBde\fP, \fBen\fP, \fBnl\fP).
.IP "\fB\-l\fP \fIlength\fP, \fB\-\-print-long\fP \fIlength\fP"
print all sentences longer than \fIlength\fP words.
.IP "\fB\-r\fP \fIari\fP, \fB\-\-print-ari\fP \fIari\fP"
print all sentences whose readability index (ARI) is greater than \fIari\fP.
.IP "\fB\-p\fP \fIpassive\fP, \fB\-\-print-passive\fP"
print all sentences phrased in the passive voice.
.IP "\fB\-N\fP \fInominalizations\fP, \fB\-\-print-nom\fP"
print all sentences containing nominalizations.
.IP "\fB\-n\fP \fInominalizations-passive\fP, \fB\-\-print-nom-passive\fP"
print all sentences  phrased in the passive voice or containing nominalizations.
.IP "\fB\-h\fP, \fB\-\-help\fP"
Print a short usage message.
.IP \fB\-\-version\fP
Print the version.
.\"}}}
.SH ERRORS \"{{{
On usage errors, 1 is returned.  Termination caused by lack of memory is
signalled by exit code 2.
.\"}}}
.SH ENVIRONMENT \"{{{
.IP "\fBLC_MESSAGES\fP=\fBde\fP\^|\^\fBen\fP\^|\^\fBnl\fP"
specifies the default document language.  The default language is \fBen\fP.
.IP "\fBLC_CTYPE\fP=\fBiso-8859-1\fP"
specifies the document character set.  The default character set is ASCII.
.\"}}}
.SH AUTHOR \"{{{
This program is GNU software, copyright 1997\(en2007 Michael Haardt <michael@moria.de>.
.PP
It contains contributions by Jason Petrone <jpetrone@acm.org>,
Uschi Stegemeier <uschi@morwain.de> and Hans Lodder.
.PP
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
.PP
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
.PP
You should have received a copy of the GNU General Public License along
with this program.  If not, write to the Free Software Foundation, Inc.,
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
.\"}}}
.SH HISTORY \"{{{
There has been a style command on old UNIX systems, which is now part
of the AT&T DWB package.  The original version was bound to roff by
enforcing a call to deroff.
.\"}}}
.SH "SEE ALSO" \"{{{
deroff(1), diction(1)
.P
Cherry, L.L.; Vesterman, W.: \fIWriting Tools\(emThe STYLE and DICTION
programs\fP, Computer Science Technical Report 91, Bell Laboratories,
Murray Hill, N.J. (1981), republished as part of the 4.4BSD User's
Supplementary Documents by O'Reilly.
.P
Coleman, M. and Liau,T.L. (1975). 'A computer readability formula designed for  
machine scoring', Journal of Applied Psychology, 60(2), 283-284.
.\"
.\" De Vries, Hugo: \fIReading Ease@WWW\fP, http://www.shlrc.mq.edu.au/~hdevries/RE.html
.\"
.\" Norbert Groeben: Leserpsychologie: Textverst�ndnis - Textverst�ndlichkeit
.\" M�nster, 1982.
.\"}}}