- Eqn
Part of the
troff suite ofUnix document layout tools, eqn is apreprocessor that formats equations for printing. A similar program, neqn, accepted the same input as eqn, but produced output tuned to look better innroff . The eqn program was created in 1974 byBrian Kernighan andLorinda Cherry .The input language used by eqn allows the user to write mathematical expressions in much the same way as they would be spoken aloud. The eqn language is similar to the mathematical component of
TeX , which appeared several years later, but is simpler and less complete.An independent compatible implementation of the eqn preprocessor has been developed by
GNU as part ofgroff , the GNU version of troff.Syntax examples
Here is how some of the examples from [http://meta.wikimedia.org/wiki/Help:Formula] would be written in eqn (with equivalents in TeX for comparison):
See also
*
troff References
*Brian W. Kernighan and Lorinda L. Cherry. "A System for Typesetting Mathematics", Communications of the ACM 18 (1975), 151–157.
External links
* [http://www.kohala.com/start/troff/v7man/eqn/eqn2e.ps Typesetting Mathematics, User's Guide (Second Edition)]
* [http://www.uwm.edu/cgi-bin/IMT/wwwman?topic=neqn(1)&msection= UNIX man page for neqn(1)]
Wikimedia Foundation. 2010.