| 1 | .SC "A Large Example" |
| 2 | .PP |
| 3 | Here is the complete source for the three display equations |
| 4 | in the abstract of this guide. |
| 5 | .sp |
| 6 | .nf |
| 7 | .ps -2 |
| 8 | .vs -2 |
| 9 | .EQ I |
| 10 | G(z)~mark =~ e sup { ln ~ G(z) } |
| 11 | ~=~ exp left ( |
| 12 | sum from k>=1 {S sub k z sup k} over k right ) |
| 13 | ~=~ prod from k>=1 e sup {S sub k z sup k /k} |
| 14 | .EN |
| 15 | .EQ I |
| 16 | lineup = left ( 1 + S sub 1 z + |
| 17 | { S sub 1 sup 2 z sup 2 } over 2! + ... right ) |
| 18 | left ( 1+ { S sub 2 z sup 2 } over 2 |
| 19 | + { S sub 2 sup 2 z sup 4 } over { 2 sup 2 cdot 2! } |
| 20 | + ... right ) ... |
| 21 | .EN |
| 22 | .EQ I |
| 23 | lineup = sum from m>=0 left ( |
| 24 | sum from |
| 25 | pile { k sub 1 ,k sub 2 ,..., k sub m >=0 |
| 26 | above |
| 27 | k sub 1 +2k sub 2 + ... +mk sub m =m} |
| 28 | { S sub 1 sup {k sub 1} } over {1 sup k sub 1 k sub 1 ! } ~ |
| 29 | { S sub 2 sup {k sub 2} } over {2 sup k sub 2 k sub 2 ! } ~ |
| 30 | ... |
| 31 | { S sub m sup {k sub m} } over {m sup k sub m k sub m ! } |
| 32 | right ) z sup m |
| 33 | .EN |
| 34 | .sp |
| 35 | .fi |
| 36 | .ps +2 |
| 37 | .vs +2 |
| 38 | .SC "Keywords, Precedences, Etc." |
| 39 | .PP |
| 40 | If you don't use braces, |
| 41 | .UC EQN |
| 42 | will |
| 43 | do operations in the order shown in this list. |
| 44 | .P1 3 |
| 45 | .ft I |
| 46 | dyad vec under bar tilde hat dot dotdot |
| 47 | fwd back down up |
| 48 | fat roman italic bold size |
| 49 | sub sup sqrt over |
| 50 | from to |
| 51 | .ft R |
| 52 | .P2 |
| 53 | These operations group to the left: |
| 54 | .P1 |
| 55 | .ft I |
| 56 | over sqrt left right |
| 57 | .ft R |
| 58 | .P2 |
| 59 | All others group to the right. |
| 60 | .PP |
| 61 | Digits, parentheses, brackets, punctuation marks, and these mathematical words |
| 62 | are converted |
| 63 | to Roman font when encountered: |
| 64 | .P1 |
| 65 | sin cos tan sinh cosh tanh arc |
| 66 | max min lim log ln exp |
| 67 | Re Im and if for det |
| 68 | .P2 |
| 69 | These character sequences are recognized and translated as shown. |
| 70 | .sp |
| 71 | .nf |
| 72 | .tr -\(mi |
| 73 | .in .5i |
| 74 | .ta 1i |
| 75 | >= $>=$ |
| 76 | <= $<=$ |
| 77 | == $==$ |
| 78 | != $!=$ |
| 79 | +- $+-$ |
| 80 | -> $->$ |
| 81 | <- $<-$ |
| 82 | << $<<$ |
| 83 | >> $>>$ |
| 84 | inf $inf$ |
| 85 | partial $partial$ |
| 86 | half $half$ |
| 87 | prime $prime$ |
| 88 | approx $approx$ |
| 89 | nothing $nothing$ |
| 90 | cdot $cdot$ |
| 91 | times $times$ |
| 92 | del $del$ |
| 93 | grad $grad$ |
| 94 | \&... $...$ |
| 95 | ,..., $,...,$ |
| 96 | sum $sum$ |
| 97 | .sp 3p |
| 98 | int $int$ |
| 99 | .sp 2p |
| 100 | prod $prod$ |
| 101 | union $union$ |
| 102 | inter $inter$ |
| 103 | .sp |
| 104 | .in |
| 105 | .fi |
| 106 | .tr -- |
| 107 | .PP |
| 108 | To obtain Greek letters, |
| 109 | simply spell them out in whatever case you want: |
| 110 | .sp |
| 111 | .nf |
| 112 | .in .2i |
| 113 | .ta .7i 1.4i 2.1i |
| 114 | DELTA $DELTA$ iota $iota$ |
| 115 | GAMMA $GAMMA$ kappa $kappa$ |
| 116 | LAMBDA $LAMBDA$ lambda $lambda$ |
| 117 | OMEGA $OMEGA$ mu $mu$ |
| 118 | PHI $PHI$ nu $nu$ |
| 119 | PI $PI$ omega $omega$ |
| 120 | PSI $PSI$ omicron $omicron$ |
| 121 | SIGMA $SIGMA$ phi $phi$ |
| 122 | THETA $THETA$ pi $pi$ |
| 123 | UPSILON $UPSILON$ psi $psi$ |
| 124 | XI $XI$ rho $rho$ |
| 125 | alpha $alpha$ sigma $sigma$ |
| 126 | beta $beta$ tau $tau$ |
| 127 | chi $chi$ theta $theta$ |
| 128 | delta $delta$ upsilon $upsilon$ |
| 129 | epsilon $epsilon$ xi $xi$ |
| 130 | eta $eta$ zeta $zeta$ |
| 131 | gamma $gamma$ |
| 132 | .sp |
| 133 | .in |
| 134 | .fi |
| 135 | .PP |
| 136 | These are all the words known to |
| 137 | .UC EQN |
| 138 | (except for characters with names), |
| 139 | together with the section where they are discussed. |
| 140 | .sp |
| 141 | .nf |
| 142 | .in .2i |
| 143 | .ta .7i 1.4i 2.1i |
| 144 | above 17, 18 lpile 17 |
| 145 | back 21 mark 15 |
| 146 | bar 13 matrix 18 |
| 147 | bold 12 ndefine 20 |
| 148 | ccol 18 over 9 |
| 149 | col 18 pile 17 |
| 150 | cpile 17 rcol 18 |
| 151 | define 20 right 16 |
| 152 | delim 19 roman 12 |
| 153 | dot 13 rpile 17 |
| 154 | dotdot 13 size 12 |
| 155 | down 21 sqrt 10 |
| 156 | dyad 13 sub 7 |
| 157 | fat 12 sup 7 |
| 158 | font 12 tdefine 20 |
| 159 | from 11 tilde 13 |
| 160 | fwd 21 to 11 |
| 161 | gfont 12 under 13 |
| 162 | gsize 12 up 21 |
| 163 | hat 13 vec 13 |
| 164 | italic 12 ~, ^ 4, 6 |
| 165 | lcol 18 { } 8 |
| 166 | left 16 "..." 8, 14 |
| 167 | lineup 15 |
| 168 | .sp |
| 169 | .in 0 |
| 170 | .fi |
| 171 | .SC Troubleshooting |
| 172 | .PP |
| 173 | If you make a mistake in an equation, |
| 174 | like leaving out a brace (very common) |
| 175 | or having one too many (very common) |
| 176 | or having a |
| 177 | .ul |
| 178 | sup |
| 179 | with nothing before it (common), |
| 180 | .UC EQN |
| 181 | will tell you with the message |
| 182 | .P1 2 |
| 183 | .ft I |
| 184 | syntax error between lines x and y, file z |
| 185 | .ft R |
| 186 | .P2 |
| 187 | where |
| 188 | .ul |
| 189 | x |
| 190 | and |
| 191 | .ul |
| 192 | y |
| 193 | are approximately the lines |
| 194 | between which the trouble occurred, and |
| 195 | .ul |
| 196 | z |
| 197 | is the name |
| 198 | of the file in question. |
| 199 | The line numbers are approximate _ look nearby as well. |
| 200 | There are also self-explanatory messages that arise if you leave out a quote |
| 201 | or try to run |
| 202 | .UC EQN |
| 203 | on a non-existent file. |
| 204 | .PP |
| 205 | If you want to check a document before actually printing it |
| 206 | (on |
| 207 | .UC UNIX |
| 208 | only), |
| 209 | .P1 |
| 210 | eqn files >/dev/null |
| 211 | .P2 |
| 212 | will |
| 213 | throw away the output but print the messages. |
| 214 | .PP |
| 215 | If you use something like dollar signs as delimiters, |
| 216 | it is easy to leave one out. |
| 217 | This causes very strange troubles. |
| 218 | The program |
| 219 | .ul |
| 220 | checkeq |
| 221 | (on |
| 222 | .UC GCOS , |
| 223 | use |
| 224 | .ul |
| 225 | \&./checkeq |
| 226 | instead) |
| 227 | checks for misplaced or missing dollar signs |
| 228 | and similar troubles. |
| 229 | .PP |
| 230 | In-line equations can only be so big |
| 231 | because of an internal buffer in |
| 232 | .UC TROFF . |
| 233 | If you get a message |
| 234 | ``word overflow'', |
| 235 | you have exceeded this limit. |
| 236 | If you print the equation as a displayed equation |
| 237 | this message will usually go away. |
| 238 | The message |
| 239 | ``line overflow'' |
| 240 | indicates you have exceeded an even bigger buffer. |
| 241 | The only cure for this is to break the equation into two separate ones. |
| 242 | .PP |
| 243 | On a related topic, |
| 244 | .UC EQN |
| 245 | does not break equations by itself _ |
| 246 | you must split long equations up across multiple lines |
| 247 | by yourself, |
| 248 | marking each by a separate |
| 249 | .UC .EQ |
| 250 | \&...\& |
| 251 | .UC .EN |
| 252 | sequence. |
| 253 | .UC EQN |
| 254 | does warn about equations that are too long |
| 255 | to fit on one line. |