.TH typo "" "" Command
.PC "Detect possible typographical and spelling errors"
\fBtypo [\-nrs][\fIfile ...\^\fB]\fR
.PP
.HS
.SH Options:
.IC "\fB\-n\fR"
Do not use built-in English statistics or dictionary
.IC "\fB\-r\fR"
Raw; do not remove nroff commands from the input
.IC "\fB\-s\fR"
Produce \fIdigrams\fR and \fItrigrams\fR files (maintenance only)
.HE
.B typo
proofreads an English-language document for typographical errors.
It conducts a statistical test of letter digrams and trigrams
in each input word against digram and trigram
frequencies throughout the entire document.
From this test,
.B typo
computes an index of peculiarity for each
word in the document.
A high index indicates a word less like other
words in the document than does a low index.
Built-in frequency tables ensure reasonable results
even for relatively short documents.
.PP
.B typo
reads each input
.I file
(or the standard input if none),
and removes punctuation and non-alphabetic characters
to produce a list of the words in the document.
To reduce the volume of the output,
.B typo
compares each word against a small dictionary of technical words and
discards it if found.
The output consists of a list of unique non-dictionary
words with associated index of peculiarity,
most peculiar first.
An index higher than ten indicates
that the word almost certainly occurs only once in the document.
.PP
.B typo
recognizes the following arguments:
.RS
.IP \fB\-n\fR
Inhibit use of the built-in English digram and trigram statistics,
and inhibit dictionary screening of words.
More words will be output and the indices of peculiarity will
be less useful for short documents.
.IP \fB\-r\fR
Inhibit the default stripping of
.B nroff
escape sequences.
Normally,
.B typo
strips lines beginning with `.'
and removes the
.B nroff
escape sequences `\e'.
.IP \fB\-s\fR
Produce output files
.B digrams
and
.B trigrams
that contain, respectively, the digram and trigram frequency
statistics for the given document.
No indices of peculiarity are calculated or printed.
If desired, these files may be installed in
directory
.BR /usr/dict .
.SH Files
\fB/tmp/typo*\fR \(em Intermediate files
.br
\fB/usr/dict/dict\fR \(em Limited dictionary
.br
\fB/usr/dict/digrams\fR \(em Digram frequency statistics
.br
\fB/usr/dict/trigrams\fR \(em Trigram frequency statistics
.SH "See Also"
.Xr "commands," commands
.Xr "nroff," nroff
.Xr "sort," sort
.Xr "spell" spell
