1`eqn(1) User Commands eqn(1)`

2`3`

`4`

## NAME

6`eqn, neqn, checkeq - typeset mathematics test`

7

## SYNOPSIS

9`eqn [-d xy] [ -f n] [-p n] [ -s n] [file]...`

10`11`

`12`

`neqn [file]...`

13`14`

`15`

`checkeq [file]...`

16`17`

## DESCRIPTION

19`eqn and neqn are language processors to assist in describing equations.`

20`eqn is a preprocessor for troff(1) and is intended for devices that can`

21`print troff's output. neqn is a preprocessor for nroff(1) and is`

22`intended for use with terminals. Usage is almost always:`

23`24`

`example% eqn file ... | troff`

25`example% neqn file ... | nroff`

26`27`

`28`

`29`

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`If no files are specified, eqn and neqn read from the standard input. A`

31`line beginning with .EQ marks the start of an equation. The end of an`

32`equation is marked by a line beginning with .EN. Neither of these lines`

33`is altered, so they may be defined in macro packages to get centering,`

34`numbering, and so on. It is also possible to set two characters as`

35```delimiters''; subsequent text between delimiters is also treated as`

36`eqn input.`

37`38`

`39`

`checkeq reports missing or unbalanced delimiters and .EQ/.EN pairs.`

40

## OPTIONS

42`The following options are supported:`

43`44`

`-dxy Sets equation delimiters set to characters x and y with the`

45`command-line argument. The more common way to do this is with`

46`delim xy between .EQ and .EN. The left and right delimiters`

47`may be identical. Delimiters are turned off by delim off`

48`appearing in the text. All text that is neither between delim‐`

49`iters nor between .EQ and .EN is passed through untouched.`

50`51`

`52`

`-fn Changes font to n globally in the document. The font can also`

53`be changed globally in the body of the document by using the`

54`gfont n directive, where n is the font specification.`

55`56`

`57`

`-pn Reduces subscripts and superscripts by n point sizes from the`

58`previous size. In the absence of the -p option, subscripts`

59`and superscripts are reduced by 3 point sizes from the previ‐`

60`ous size.`

61`62`

`63`

`-sn Changes point size to n globally in the document. The point`

64`size can also be changed globally in the body of the document`

65`by using the gsize n directive, where n is the point size.`

66`67`

## OPERANDS

69`The following operands are supported:`

70`71`

`file The nroff or troff file processed by eqn or neqn.`

72`73`

## EQN LANGUAGE

75`The nroff version of this description depicts the output of neqn to`

76`the terminal screen exactly as neqn is able to display it. To see an`

77`accurate depiction of the output, view the printed version of this`

78`page.`

79`80`

`81`

`Tokens within eqn are separated by braces, double quotes, tildes, cir‐`

82`cumflexes, SPACE, TAB, or NEWLINE characters. Braces {} are used for`

83`grouping. Generally speaking, anywhere a single character like x could`

84`appear, a complicated construction enclosed in braces may be used`

85`instead. A tilde (~) represents a full SPACE in the output; a circum‐`

86`flex (^) half as much.`

87`88`

`Subscripts and superscripts:`

89`90`

`These are produced with the keywords sub and sup.`

91`92`

`x sub i makes xi`

93`94`

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`96`

`a sub i sup 2 produces a2i`

97`98`

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`e sup {x sup 2 + y sup 2} gives e^(x^2+y^2)`

101`102`

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`Fractions:`

106`107`

`Fractions are made with over.`

108`109`

`a over b yields ab_`

110`111`

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`113`

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`Square Roots:`

115`116`

`These are made with sqrt`

117`118`

`1 over sqrt {ax sup 2 +bx+c}`

119`120`

`results in √_a_x_2_+_1b_x_+_c__`

121`122`

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`Limits:`

126`127`

`The keywords from and to introduce lower and upper limits on arbi‐`

128`trary things:`

129`130`

`lim from {n→ inf } sum from 0 to n x sub i`

131`132`

`makes nl→i∞mn0Σxi`

133`134`

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`Brackets and Braces:`

138`139`

`Left and right brackets, braces, and the like, of the right height`

140`are made with left and right.`

141`142`

`left [ x sup 2 + y sup 2 over alpha right ] ~=~1`

143`144`

`produces ⎡⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎢⎣x2+y_2α_⎤⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎥⎦=1`

145`146`

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`The right clause is optional. Legal characters after left and`

148`right are braces, brackets, bars, c and f for ceiling and`

149`floor, and "" for nothing at all (useful for a right-side-only`

150`bracket).`

151`152`

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`Vertical piles:`

155`156`

`Vertical piles of things are made with pile, lpile, cpile, and`

157`rpile.`

158`a`

159`pile {a above b above c} produces b`

160`c`

161`162`

`163`

`There can be an arbitrary number of`

164`elements in a pile. lpile left-justi‐`

165`fies, pile and cpile center, with dif‐`

166`ferent vertical spacing, and rpile`

167`right justifies.`

168`169`

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`Matrices:`

172`173`

`Matrices are made with matrix.`

174`175`

`matrix { lcol { x sub i above y sub 2 } ccol { 1 above 2 } }`

176`177`

`produces xi 1`

178`y2 2`

179`180`

`In addition, there is rcol for a right-justified column.`

181`182`

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`184`

`Diacritical marks:`

185`186`

`Diacritical marks are made with dot, dotdot, hat, tilde, bar, vec,`

187`dyad, and under.`

188`189`

`x dot = f(t) bar is ˙x=_f_(_t_)`

190`191`

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`y dotdot bar ~=~ n under is _¨y=_n`

194`195`

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`x vec ~=~ y dyad is →x=↔y`

198`199`

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`Sizes and Fonts:`

203`204`

`Sizes and font can be changed with size n or size ±n, roman,`

205`italic, bold, and font n. Size and fonts can be changed globally in`

206`a document by gsize n and gfont n, or by the command-line arguments`

207`-sn and -fn.`

208`209`

`210`

`Successive display arguments:`

211`212`

`Successive display arguments can be lined up. Place mark before`

213`the desired lineup point in the first equation; place lineup at the`

214`place that is to line up vertically in subsequent equations.`

215`216`

`217`

`Shorthands:`

218`219`

`Shorthands may be defined or existing keywords redefined with`

220`define:`

221`222`

`define thing % replacement %`

223`224`

`Defines a new token called thing which will be replaced by`

225`replacement whenever it appears thereafter. The % may be any`

226`character that does not occur in replacement.`

227`228`

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`Keywords and Shorthands:`

231`232`

`Keywords like sum int inf and shorthands like >= → and != are rec‐`

233`ognized.`

234`235`

`236`

`Greek letters:`

237`238`

`Greek letters are spelled out in the desired case, as in alpha or`

239`GAMMA.`

240`241`

`242`

`Mathematical words:`

243`244`

`Mathematical words like sin, cos, and log are made Roman automat‐`

245`ically.`

246`247`

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`249`

`troff(1) four-character escapes like · (·) can be used anywhere.`

250`Strings enclosed in double quotes "..." are passed through untouched;`

251`this permits keywords to be entered as text, and can be used to commu‐`

252`nicate with troff when all else fails.`

253

## ATTRIBUTES

255`See attributes(5) for descriptions of the following attributes:`

256`257`

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`┌─────────────────────────────┬─────────────────────────────┐`

261`│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │`

262`├─────────────────────────────┼─────────────────────────────┤`

263`│Availability │SUNWdoc │`

264`└─────────────────────────────┴─────────────────────────────┘`

265

## SEE ALSO

267`nroff(1), tbl(1), troff(1), attributes(5), ms(5)`

268

## BUGS

270`To embolden characters such as digits and parentheses, it is necessary`

271`to quote them, as in `bold "12.3"'.`

272`273`

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`SunOS 5.11 12 Jul 2002 eqn(1)`