| 1 | .EQ |
| 2 | delim $$ |
| 3 | .EN |
| 4 | .TH EQN 1 2/22/74 |
| 5 | .SH NAME |
| 6 | eqn, neqn, checkeq \- typeset mathematics |
| 7 | .SH SYNOPSIS |
| 8 | .B eqn |
| 9 | [ |
| 10 | .BR \-d xy |
| 11 | ] [ |
| 12 | .BR \-p n |
| 13 | ] [ |
| 14 | .BR \-s n |
| 15 | ] [ |
| 16 | .BR \-f n |
| 17 | ] |
| 18 | [ file ] ... |
| 19 | .br |
| 20 | .B checkeq |
| 21 | [ file ] ... |
| 22 | .SH DESCRIPTION |
| 23 | .I Eqn |
| 24 | is a |
| 25 | troff(1) |
| 26 | preprocessor |
| 27 | for typesetting mathematics |
| 28 | on a Graphic Systems phototypesetter, |
| 29 | .I neqn |
| 30 | on terminals. |
| 31 | Usage is almost always |
| 32 | .PP |
| 33 | eqn file ... | troff |
| 34 | .br |
| 35 | neqn file ... | nroff |
| 36 | .PP |
| 37 | If no files are specified, |
| 38 | these programs |
| 39 | reads from the standard input. |
| 40 | A line beginning with `.EQ' marks the start of an equation; |
| 41 | the end of an equation |
| 42 | is marked by a line beginning with `.EN'. |
| 43 | Neither of these lines is altered, |
| 44 | so they may be defined in macro packages |
| 45 | to get |
| 46 | centering, numbering, etc. |
| 47 | It is also possible to set two characters as `delimiters'; |
| 48 | subsequent text between delimiters is also treated as |
| 49 | .ul |
| 50 | eqn |
| 51 | input. |
| 52 | Delimiters may be set to characters |
| 53 | .I x |
| 54 | and |
| 55 | .I y |
| 56 | with the command-line argument |
| 57 | .BI \-d xy |
| 58 | or (more commonly) with |
| 59 | `delim |
| 60 | .IR xy ' |
| 61 | between .EQ and .EN. |
| 62 | The left and right delimiters may be identical. |
| 63 | Delimiters are turned off by `delim off'. |
| 64 | All text that is neither between delimiters nor between .EQ and .EN |
| 65 | is passed through untouched. |
| 66 | .PP |
| 67 | The program |
| 68 | .I checkeq |
| 69 | reports missing or unbalanced delimiters and .EQ/.EN pairs. |
| 70 | .PP |
| 71 | Tokens within |
| 72 | .I eqn |
| 73 | are separated by |
| 74 | spaces, tabs, newlines, braces, double quotes, |
| 75 | tildes or circumflexes. |
| 76 | Braces {} are used for grouping; |
| 77 | generally speaking, |
| 78 | anywhere a single character like |
| 79 | .I x |
| 80 | could appear, a complicated construction |
| 81 | enclosed in braces may be used instead. |
| 82 | Tilde ~ represents a full space in the output, |
| 83 | circumflex ^ half as much. |
| 84 | .PP |
| 85 | .vs 13p |
| 86 | Subscripts and superscripts are produced with the keywords |
| 87 | .B sub |
| 88 | and |
| 89 | .B sup. |
| 90 | Thus |
| 91 | .I "x sub i" |
| 92 | makes |
| 93 | $x sub i$, |
| 94 | .I "a sub i sup 2" |
| 95 | produces |
| 96 | $a sub i sup 2$, |
| 97 | and |
| 98 | .I "e sup {x sup 2 + y sup 2}" |
| 99 | gives |
| 100 | $e sup {x sup 2 + y sup 2}$. |
| 101 | .PP |
| 102 | Fractions are made with |
| 103 | .BR over : |
| 104 | .I "a over b" |
| 105 | yields $a over b$. |
| 106 | .PP |
| 107 | .B sqrt |
| 108 | makes square roots: |
| 109 | .I "1 over sqrt {ax sup 2 +bx+c}" |
| 110 | results in |
| 111 | $1 over sqrt {ax sup 2 +bx+c}$ . |
| 112 | .PP |
| 113 | The keywords |
| 114 | .B from |
| 115 | and |
| 116 | .B to |
| 117 | introduce lower and upper |
| 118 | limits on arbitrary things: |
| 119 | $lim from {n-> inf} sum from 0 to n x sub i$ |
| 120 | is made with |
| 121 | .I "lim from {n\-> inf } sum from 0 to n x sub i." |
| 122 | .PP |
| 123 | Left and right brackets, braces, etc., of the right height are made with |
| 124 | .B left |
| 125 | and |
| 126 | .B right: |
| 127 | .I "left [ x sup 2 + y sup 2 over alpha right ] ~=~1" |
| 128 | produces |
| 129 | $left [ x sup 2 + y sup 2 over alpha right ] ~=~1$. |
| 130 | The |
| 131 | .B right |
| 132 | clause is optional. |
| 133 | Legal characters after |
| 134 | .B left |
| 135 | and |
| 136 | .B right |
| 137 | are braces, brackets, bars, |
| 138 | .B c |
| 139 | and |
| 140 | .B f |
| 141 | for ceiling and floor, |
| 142 | and "" for nothing at all (useful for a right-side-only bracket). |
| 143 | .PP |
| 144 | Vertical piles of things are made with |
| 145 | .BR pile , |
| 146 | .BR lpile , |
| 147 | .BR cpile , |
| 148 | and |
| 149 | .BR rpile : |
| 150 | .I "pile {a above b above c}" |
| 151 | produces |
| 152 | $pile {a above b above c}$. |
| 153 | There can be an arbitrary number of elements in a pile. |
| 154 | .B lpile |
| 155 | left-justifies, |
| 156 | .B pile |
| 157 | and |
| 158 | .B cpile |
| 159 | center, with different vertical spacing, |
| 160 | and |
| 161 | .B rpile |
| 162 | right justifies. |
| 163 | .PP |
| 164 | Matrices are made with |
| 165 | .BR matrix : |
| 166 | .I "matrix { lcol { x sub i above y sub 2 } ccol { 1 above 2 } }" |
| 167 | produces |
| 168 | $matrix { lcol { x sub i above y sub 2 } ccol { 1 above 2 } }$. |
| 169 | In addition, there is |
| 170 | .B rcol |
| 171 | for a right-justified column. |
| 172 | .PP |
| 173 | .vs 12p |
| 174 | Diacritical marks are made with |
| 175 | .BR dot , |
| 176 | .BR dotdot , |
| 177 | .BR hat , |
| 178 | .BR tilde , |
| 179 | .BR bar , |
| 180 | .BR vec , |
| 181 | .BR dyad , |
| 182 | and |
| 183 | .BR under : |
| 184 | .I "x dot = f(t) bar" |
| 185 | is |
| 186 | $x dot = f(t) bar$, |
| 187 | .I "y dotdot bar ~=~ n under" |
| 188 | is |
| 189 | $y dotdot bar ~=~ n under$, |
| 190 | and |
| 191 | .I "x vec ~=~ y dyad" |
| 192 | is |
| 193 | $x vec ~=~ y dyad$. |
| 194 | .PP |
| 195 | Sizes and font can be changed with |
| 196 | .B size |
| 197 | .I n |
| 198 | or |
| 199 | .B size |
| 200 | .BI \(+- n, |
| 201 | .BR roman , |
| 202 | .BR italic , |
| 203 | .BR bold , |
| 204 | and |
| 205 | .BR font |
| 206 | .I n. |
| 207 | Size and fonts can be changed globally in a document by |
| 208 | .B gsize |
| 209 | .I n |
| 210 | and |
| 211 | .B gfont |
| 212 | .IR n , |
| 213 | or by the command-line arguments |
| 214 | .BI \-s n |
| 215 | and |
| 216 | .BI \-f n. |
| 217 | .PP |
| 218 | Normally subscripts and superscripts are reduced by |
| 219 | 3 point sizes from the previous size; |
| 220 | this may be changed by the command-line argument |
| 221 | .BI \-p n. |
| 222 | .PP |
| 223 | Successive display arguments can be lined up. |
| 224 | Place |
| 225 | .B mark |
| 226 | before the desired lineup point in the first equation; |
| 227 | place |
| 228 | .B lineup |
| 229 | at the place that is to line up vertically in subsequent equations. |
| 230 | .PP |
| 231 | Shorthands may be defined |
| 232 | or existing keywords redefined with |
| 233 | .BI define : |
| 234 | .I "define thing % replacement %" |
| 235 | defines a new token called |
| 236 | .I thing |
| 237 | which will be replaced by |
| 238 | .I replacement |
| 239 | whenever it appears thereafter. |
| 240 | The |
| 241 | .I % |
| 242 | may be any character that does not occur in |
| 243 | .I replacement. |
| 244 | .PP |
| 245 | Keywords like |
| 246 | .I sum |
| 247 | .EQ |
| 248 | ( sum ) |
| 249 | .EN |
| 250 | .I int |
| 251 | .EQ |
| 252 | ( int ) |
| 253 | .EN |
| 254 | .I inf |
| 255 | .EQ |
| 256 | ( inf ) |
| 257 | .EN |
| 258 | and shorthands like |
| 259 | >= |
| 260 | .EQ |
| 261 | (>=) |
| 262 | .EN |
| 263 | \-> |
| 264 | .EQ |
| 265 | (->), |
| 266 | .EN |
| 267 | and |
| 268 | != |
| 269 | .EQ |
| 270 | ( != ) |
| 271 | .EN |
| 272 | are recognized. |
| 273 | Greek letters are spelled out in the desired case, as in |
| 274 | .I alpha |
| 275 | or |
| 276 | .I GAMMA. |
| 277 | Mathematical words like sin, cos, log are made Roman automatically. |
| 278 | .IR Troff (1) |
| 279 | four-character escapes like \e(bs (\(bs) |
| 280 | can be used anywhere. |
| 281 | Strings enclosed in double quotes "..." |
| 282 | are passed through untouched; |
| 283 | this permits keywords to be entered as text, |
| 284 | and can be used to communicate |
| 285 | with |
| 286 | .I troff |
| 287 | when all else fails. |
| 288 | .SH "SEE ALSO" |
| 289 | .PP |
| 290 | troff(1), tbl(1), ms(7), eqnchar(7) |
| 291 | .br |
| 292 | B. W. Kernighan and L. L. Cherry, |
| 293 | .ul |
| 294 | Typesetting Mathematics\(emUser's Guide |
| 295 | .br |
| 296 | J. F. Ossanna, |
| 297 | .ul |
| 298 | NROFF/TROFF User's Manual |
| 299 | .SH BUGS |
| 300 | .PP |
| 301 | To embolden digits, parens, etc., |
| 302 | it is necessary to quote them, |
| 303 | as in `bold "12.3"'. |