eqn, neqn, checkeq - (BSD) typeset mathematics

Synopsis

Description

See Also

Notes

/usr/ucb/eqn[-dxy] [-fn] [-sn] [file] ...

/usr/ucb/neqn[file] ...

/usr/ucb/checkeq

Eqnis a troff(1B) preprocessor for typesetting mathematics on a phototypesetter,neqnon terminals. Usage is almost alwayseqn file ... | troff

neqn file ... | nroffIf no files are specified, these programs read from the standard input. A line beginning with '.EQ' marks the start of an equation; the end of an equation is marked by a line beginning with '.EN'. Neither of these lines is altered, so they may be defined in macro packages to get centering, numbering, etc. It is also possible to set two characters as 'delimiters'; subsequent text between delimiters is also treated as eqn input. Delimiters may be set to characters

xandywith the command-line argument-dxyor (more commonly) with 'delimxy' between .EQ and .EN. The left and right delimiters may be identical. Delimiters are turned off by 'delim off'. All text that is neither between delimiters nor between .EQ and .EN is passed through untouched.The program

checkeqreports missing or unbalanced delimiters and .EQ/.EN pairs.Tokens within

eqnare separated by spaces, tabs, newlines, braces, double quotes, tildes or circumflexes. Braces {} are used for grouping; generally speaking, anywhere a single character likexcould appear, a complicated construction enclosed in braces may be used instead. Tilde ~ represents a full space in the output, circumflex ^ half as much.Subscripts and superscripts are produced with the keywords

subandsup.Thusx sub imakesx_{i},a sub i sup 2producesa_{i}^{2}, ande sup {x sup 2 + y sup 2}givese^{x}^{2}^{+y}^{2}^{}.Fractions are made with

over:a over byieldsa/b.

sqrtmakes square roots:1 over sqrt {ax sup 2 +bx+c}results in 1 / sqrtax^{2}+bx+c .The keywords

fromandtointroduce lower and upper limits on arbitrary things:

lim_{n->oo}sum_{0}^{n}x_{i}is made withlim from {n-> inf } sum from 0 to n x sub i.Left and right brackets, braces, etc., of the right height are made with

leftandright:left [ x sup 2 + y sup 2 over alpha right ] ~=~1produces [x^{2}+y^{2}/alpha] = 1. Therightclause is optional. Legal characters afterleftandrightare braces, brackets, bars,candffor ceiling and floor, and "" for nothing at all (useful for a right-side-only bracket).Vertical piles of things are made with

pile,lpile,cpile, andrpile:pile {a above b above c}produces

pileabc. There can be an arbitrary number of elements in a pile.lpileleft-justifies,pileandcpilecenter, with different vertical spacing, andrpileright justifies.Matrices are made with

matrix:matrix { lcol { x sub i above y sub 2 } ccol { 1 above 2 } }produces matrix (x_{i}y_{2}1 2 ). In addition, there isrcolfor a right-justified column.Diacritical marks are made with

dot,dotdot,hat,tilde,bar,vec,dyad, andunder:x dot = f(t) barisx^{.}=f(t)^{–},y dotdot bar ~=~ n underisy^{..}^{–}=n_ , andx vec ~=~ y dyadisx^{–}=ydyad.Sizes and font can be changed with

sizenorsize±n,roman,italic,bold, andfontn.Size and fonts can be changed globally in a document bygsizenandgfontn, or by the command-line arguments-snand-fn.Normally subscripts and superscripts are reduced by 3 point sizes from the previous size; this may be changed by the command-line argument

-pn.Successive display arguments can be lined up. Place

markbefore the desired lineup point in the first equation; placelineupat the place that is to line up vertically in subsequent equations.Shorthands may be defined or existing keywords redefined with

define:define thing % replacement %defines a new token calledthingwhich will be replaced byreplacementwhenever it appears thereafter. The%may be any character that does not occur inreplacement.Keywords like

sum( sum )int( int )inf(oo) and shorthands like >= (>=) -> (->), and != (!=) are recognized. Greek letters are spelled out in the desired case, as inalphaorGAMMA.Mathematical words like sin, cos, log are made Roman automatically.Troff(1B) four-character escapes like \(bs () can be used anywhere. Strings enclosed in double quotes "..." are passed through untouched; this permits keywords to be entered as text, and can be used to communicate withtroffwhen all else fails.

troff(1B), tbl(1B), ms(7), eqnchar(7B)

B. W. Kernighan and L. L. Cherry, Typesetting Mathematics—User's Guide

J. F. Ossanna, NROFF/TROFF User's Manual

To embolden digits, parens, etc., it is necessary to quote them, as in 'bold "12.3"'.

Heirloom Documentation Tools | EQN (1B) | 12/12/05 |