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86f6a31e | 1 | % \begin{meta-comment} |
2 | % | |
4a655c6f | 3 | % $Id: mdwmath.dtx,v 1.2 2003/09/05 16:14:36 mdw Exp $ |
86f6a31e | 4 | % |
5 | % Various nicer mathematical things | |
6 | % | |
4a655c6f | 7 | % (c) 2003 Mark Wooding |
86f6a31e | 8 | % |
86f6a31e | 9 | % \end{meta-comment} |
10 | % | |
11 | % \begin{meta-comment} <general public licence> | |
12 | %% | |
13 | %% mdwmath package -- various nicer mathematical things | |
4a655c6f | 14 | %% Copyright (c) 2003 Mark Wooding |
86f6a31e | 15 | %% |
16 | %% This program is free software; you can redistribute it and/or modify | |
17 | %% it under the terms of the GNU General Public License as published by | |
18 | %% the Free Software Foundation; either version 2 of the License, or | |
19 | %% (at your option) any later version. | |
20 | %% | |
21 | %% This program is distributed in the hope that it will be useful, | |
22 | %% but WITHOUT ANY WARRANTY; without even the implied warranty of | |
23 | %% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
24 | %% GNU General Public License for more details. | |
25 | %% | |
26 | %% You should have received a copy of the GNU General Public License | |
27 | %% along with this program; if not, write to the Free Software | |
28 | %% Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
29 | %% | |
30 | % \end{meta-comment} | |
31 | % | |
32 | % \begin{meta-comment} <Package preamble> | |
33 | %<+package>\NeedsTeXFormat{LaTeX2e} | |
34 | %<+package>\ProvidesPackage{mdwmath} | |
4a655c6f | 35 | %<+package> [2003/08/25 1.3 Nice mathematical things] |
86f6a31e | 36 | %<+oldeqnarray>\NeedsTeXFormat{LaTeX2e} |
37 | %<+oldeqnarray>\ProvidesPackage{eqnarray} | |
38 | %<+oldeqnarray> [1996/04/11 1.1 Old enhanced eqnarray] | |
39 | % \end{meta-comment} | |
40 | % | |
3ba7380e | 41 | % \CheckSum{740} |
86f6a31e | 42 | %% \CharacterTable |
43 | %% {Upper-case \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z | |
44 | %% Lower-case \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z | |
45 | %% Digits \0\1\2\3\4\5\6\7\8\9 | |
46 | %% Exclamation \! Double quote \" Hash (number) \# | |
47 | %% Dollar \$ Percent \% Ampersand \& | |
48 | %% Acute accent \' Left paren \( Right paren \) | |
49 | %% Asterisk \* Plus \+ Comma \, | |
50 | %% Minus \- Point \. Solidus \/ | |
51 | %% Colon \: Semicolon \; Less than \< | |
52 | %% Equals \= Greater than \> Question mark \? | |
53 | %% Commercial at \@ Left bracket \[ Backslash \\ | |
54 | %% Right bracket \] Circumflex \^ Underscore \_ | |
55 | %% Grave accent \` Left brace \{ Vertical bar \| | |
56 | %% Right brace \} Tilde \~} | |
57 | %% | |
58 | % | |
59 | % \begin{meta-comment} | |
60 | % | |
61 | %<*driver> | |
62 | \input{mdwtools} | |
63 | \let\opmod\pmod | |
64 | \usepackage{amssymb} | |
65 | \describespackage{mdwmath} | |
4a655c6f | 66 | %\describespackage{eqnarray} |
86f6a31e | 67 | \ignoreenv{old-eqnarray} |
4a655c6f | 68 | %\unignoreenv{old-eqnarray} |
86f6a31e | 69 | \mdwdoc |
70 | %</driver> | |
71 | % | |
72 | % \end{meta-comment} | |
73 | % | |
74 | % \section{User guide} | |
75 | % | |
76 | % \subsection{Square root typesetting} | |
77 | % | |
78 | % \DescribeMacro{\sqrt} | |
79 | % The package supplies a star variant of the |\sqrt| command which omits the | |
80 | % vinculum over the operand (the line over the top). While this is most | |
81 | % useful in simple cases like $\sqrt*{2}$ it works for any size of operand. | |
82 | % The package also re-implements the standard square root command so that it | |
83 | % positions the root number rather better. | |
84 | % | |
85 | % \begin{figure} | |
86 | % \begin{demo}[w]{Examples of the new square root command} | |
87 | %\[ \sqrt*{2} \quad \mbox{rather than} \quad \sqrt{2} \] | |
88 | %\[ \sqrt*[3]{2} \quad \mbox{ rather than } \quad \sqrt[3]{2} \] | |
89 | %\[ \sqrt{x^3 + \sqrt*[y]{\alpha}} - \sqrt*[n+1]{a} \] | |
90 | %\[ x = \sqrt*[3]{\frac{3y}{7}} \] | |
91 | %\[ q = \frac{2\sqrt*{2}}{5}+\sqrt[\frac{n+1}{2}]{2x^2+3xy-y^2} \] | |
92 | % \end{demo} | |
93 | % \end{figure} | |
94 | % | |
95 | % [Note that omission of the vinculum was originally a cost-cutting exercise | |
96 | % because the radical symbol can just fit in next to its operand and | |
97 | % everything ends up being laid out along a line. However, I find that the | |
98 | % square root without vinculum is less cluttered, so I tend to use it when | |
99 | % it doesn't cause ambiguity.] | |
100 | % | |
101 | % \subsection{Modular arithmetic} | |
102 | % | |
103 | % In standard maths mode, there's too much space before the parentheses in | |
104 | % the output of the |\pmod| command. Suppose that $x \equiv y^2 \opmod n$: | |
105 | % then the spacing looks awful. Go on, admit it. | |
106 | % | |
107 | % It looks OK in a display. For example, if | |
108 | % \[ c \equiv m^e \opmod n \] | |
109 | % then it's fine. The package redefines the |\pmod| command to do something | |
110 | % more sensible. So now $c^d \equiv m^{ed} \equiv m \pmod n$ and all looks | |
111 | % fine. | |
112 | % | |
113 | % \subsection{Some maths symbols you already have} | |
114 | % | |
115 | % \DescribeMacro\bitor | |
116 | % \DescribeMacro\bitand | |
117 | % \DescribeMacro\dblor | |
118 | % \DescribeMacro\dbland | |
119 | % Having just tried to do some simple things, I've found that there are maths | |
120 | % symbols missing. Here they are, in all their glory: | |
121 | % \begin{center} \unverb\| \begin{tabular}{cl|cl|cl} | |
eafdddad MW |
122 | % $\&$ & "\&" & $\bitor$ & "\bitor" & $\dbland$ & "\dbland" \\ |
123 | % $\bitand$ & "\bitand" & $\dblor$ & "\dblor" & | |
86f6a31e | 124 | % \end{tabular} \end{center} |
125 | % | |
126 | % \DescribeMacro\xor | |
127 | % \DescribeMacro\cat | |
128 | % I also set up the |\xor| command to typeset `$\xor$', which is commonly | |
129 | % used to represent the bitsize exclusive-or operation among cryptographers. | |
130 | % The command |\cat| typesets `$\cat$', which is a common operator indicating | |
131 | % concatenation of strings. | |
132 | % | |
133 | % \DescribeMacro\lsl | |
134 | % \DescribeMacro\lsr | |
135 | % \DescribeMacro\rol | |
136 | % \DescribeMacro\ror | |
137 | % The commands |\lsl| and |\lsr| typeset binary operators `$\lsl$' and | |
138 | % `$\lsr$' respectively, and |\rol| and |\ror| typeset `$\rol$' and `$\ror$'. | |
139 | % Note that these are spaced as binary operators, rather than relations. | |
140 | % | |
141 | % \DescribeMacro\compose | |
142 | % \DescribeMacro\implies | |
143 | % \DescribeMacro\vect | |
144 | % The |\compose| command typesets `$\compose$', which is usually used to | |
145 | % denote function composition. The |\implies| command is made to typeset | |
146 | % `$\implies$'. And \syntax{"\\vect{"<x>"}"} typesets `$\vect{x}$'. | |
147 | % | |
148 | % \DescribeMacro\statclose | |
149 | % \DescribeMacro\compind | |
150 | % The |\statclose| command typesets `$\statclose$', which indicates | |
151 | % `statistical closeness' of probability distributions; |\compind| typesets | |
152 | % `$\compind$', which indicates computational indistinguishability. | |
153 | % | |
4a655c6f | 154 | % \subsection{Fractions} |
155 | % | |
156 | % \DescribeMacro\fracdef | |
157 | % We provide a general fraction system, a little tiny bit like | |
158 | % \package{amsmath}'s |\genfrac|. Say | |
159 | % \syntax{"\\fracdef{"<name>"}{"<frac-params>"}"} to define a new | |
160 | % |\frac|-like operator. The \<frac-params> are a comma-separated list of | |
161 | % parameters: | |
162 | % \begin{description} | |
163 | % \item[\lit*{line}] Include a horizontal line between the top and bottom | |
164 | % (like |\frac|). | |
165 | % \item[\lit*{line=}\<length>] Include a horizontal line with width | |
166 | % \<length>. | |
167 | % \item[\lit*{noline}] Don't include a line (like |\binom|). | |
168 | % \item[\lit*{leftdelim=}\<delim>] Use \<delim> as the left-hand delimiter. | |
169 | % \item[\lit*{rightdelim=}\<delim>] Use \<delim> as the right-hand delimiter. | |
170 | % \item[\lit*{nodelims}] Don't include delimiters. | |
171 | % \item[\lit*{style=}\<style>] Typeset the fraction in \<style>, which is one | |
172 | % of |display|, |text|, |script| or |scriptscript|. | |
173 | % \item[\lit*{style}] Use the prevailing style for the fraction. | |
174 | % \item[\lit*{innerstyle=}\<style>] Typeset the \emph{components} of the | |
175 | % fraction in \<style>. | |
176 | % \item[\lit*{innerstyle}] Typeset the fraction components according to the | |
177 | % prevailing style. | |
178 | % \end{description} | |
179 | % The commands created by |\fracdef| have the following syntax: | |
180 | % \syntax{<name>"["<frac-params>"]{"<top>"}{"<bottom>"}"}. Thus, you can use | |
181 | % the optional argument to `tweak' the fraction if necessary. This isn't | |
182 | % such a good idea to do often. | |
183 | % | |
184 | % \DescribeMacro\frac | |
185 | % \DescribeMacro\binom | |
86f6a31e | 186 | % \DescribeMacro\jacobi |
4a655c6f | 187 | % The macros |\frac|, |\binom| and |\jacobi| are defined using |\fracdef|. |
188 | % They typset $\frac{x}{y}$, $\binom{n}{k}$ and $\jacobi{x}{n}$ respectively. | |
189 | % (The last may be of use to number theorists talking about Jacobi or | |
190 | % Lagrange symbols.) | |
191 | % | |
192 | % By way of example, these commands were defined using | |
193 | %\begin{verbatim} | |
194 | %\fracdef\frac{nodelims, line} | |
195 | %\fracdef\binom{leftdelim = (, rightdelim = ), noline} | |
196 | %\fracdef\jacobi{leftdelim = (, rightdelim = ), line} | |
197 | %\end{verbatim} | |
86f6a31e | 198 | % |
199 | % \subsection{Rant about derivatives} | |
200 | % | |
201 | % \DescribeMacro\d | |
202 | % There is a difference between UK and US typesetting of derivatives. | |
203 | % Americans typeset | |
204 | % \[ \frac{dy}{dx} \] | |
205 | % while the British want | |
206 | % \[ \frac{\d y}{\d x}. \] | |
4a655c6f | 207 | % The command |\d| command is fixed to typeset a `$\d$'. (In text mode, |
208 | % |\d{x}| still typesets `\d{x}'.) | |
86f6a31e | 209 | % |
210 | % \subsection{New operator names} | |
211 | % | |
212 | % \DescribeMacro\keys | |
213 | % \DescribeMacro\dom | |
214 | % \DescribeMacro\ran | |
215 | % \DescribeMacro\supp | |
216 | % \DescribeMacro\lcm | |
4a655c6f | 217 | % \DescribeMacro\ord |
218 | % \DescribeMacro\poly | |
219 | % \DescribeMacro\negl | |
86f6a31e | 220 | % A few esoteric new operator names are supplied. |
221 | % \begin{center} \unverb\| \begin{tabular}{cl|cl|cl} | |
eafdddad MW |
222 | % $\keys$ & "\keys" & $\dom$ & "\dom" & $\ran$ & "\ran" \\ |
223 | % $\supp$ & "\supp" & $\lcm$ & "\lcm" & $\ord$ & "\ord" \\ | |
224 | % $\poly$ & "\poly" & $\negl$ & "\negl" | |
86f6a31e | 225 | % \end{tabular} \end{center} |
226 | % I think |\lcm| ought to be self-explanatory. The |\dom| and |\ran| | |
227 | % operators pick out the domain and range of a function, respectively; thus, | |
228 | % if $F\colon X \to Y$ is a function, then $\dom F = X$ and $\ran F = Y$. | |
229 | % The \emph{support} of a probability distribution $\mathcal{D}$ is the set | |
230 | % of objects with nonzero probability; i.e., $\supp{D} = \{\, x \in | |
4a655c6f | 231 | % \dom\mathcal{D} \mid \mathcal{D}(x) > 0 \,\}$. If $g \in G$ is a group |
232 | % element then $\ord g$ is the \emph{order} of $g$; i.e., the smallest | |
233 | % positive integer $i$ where $g^i$ is the identity element, or $0$ if there | |
234 | % is no such $i$. $\poly(n)$ is some polynomial function of $n$. A function | |
235 | % $\nu(\cdot)$ is \emph{negligible} if, for every polynomial function | |
236 | % $p(\cdot)$, there is an integer $N$ such that $\nu(n) < 1/p(n)$ for all $n | |
237 | % > N$; $\negl(n)$ is some negligible function of $n$. | |
86f6a31e | 238 | % |
239 | % \subsection{Standard set names} | |
240 | % | |
241 | % \DescribeMacro\Z | |
242 | % \DescribeMacro\Q | |
243 | % \DescribeMacro\R | |
244 | % \DescribeMacro\C | |
245 | % \DescribeMacro\N | |
246 | % \DescribeMacro\F | |
247 | % \DescribeMacro\powerset | |
4a655c6f | 248 | % \DescribeMacro\gf |
86f6a31e | 249 | % If you have a |\mathbb| command defined, the following magic is revealed: |
250 | % \begin{center} \unverb\| \begin{tabular}{cl|cl|cl} | |
251 | % $\Z$ & "\Z" & $\Q$ & "\Q" & $\R$ & "\R" \\ | |
252 | % $\N$ & "\N" & $\F$ & "\F" & $\C$ & "\C" | |
253 | % \end{tabular} \end{center} | |
254 | % which are handy for various standard sets of things. Also the |\powerset| | |
4a655c6f | 255 | % command typesets `$\powerset$', and \syntax{"\\gf{"<q>"}"}, which by default |
256 | % typesets $\gf{\syntax{<q>}}$ but you might choose to have it set | |
257 | % $\mathrm{GF}(\syntax{<q>})$ intead. | |
258 | % | |
259 | % \subsection{Biggles} | |
260 | % | |
261 | % \DescribeMacro\bbigg | |
262 | % \DescribeMacro\bbiggl | |
263 | % \DescribeMacro\bbiggr | |
264 | % \DescribeMacro\bbiggm | |
265 | % The |\bbigg| commands generalizes the Plain \TeX\ |\bigg| family of | |
266 | % macros. |\bbigg| produces an `ordinary' symbol; |\bbiggl| and |\bbiggr| | |
267 | % produce left and right delimiters; and |\bbiggm| produces a relation. They | |
268 | % produce symbols whose size is related to the prevailing text size -- so | |
269 | % they adjust correctly in chapter headings, for example. | |
270 | % | |
271 | % The syntax is straightforward: | |
272 | % \syntax{"\\"<bigop>"["$a$"]{"$n$"}{"<delim>"}"}. Describing it is a bit | |
273 | % trickier. The size is based on the current |\strut| height. If |\strut| | |
274 | % has a height of $h$ and a depth of $d$, then the delimiter produced has a | |
275 | % height of $n \times (h + d + a)$. | |
276 | % | |
277 | % The old |\big| commands have been redefined in terms of |\bbigg|. | |
86f6a31e | 278 | % |
279 | % \subsection{The `QED' symbol} | |
280 | % | |
281 | % \DescribeMacro\qed | |
282 | % \DescribeMacro\qedrule | |
283 | % For use in proofs of theorems, we provide a `QED' symbol which behaves well | |
284 | % under bizarre line-splitting conditions. To use it, just say |\qed|. The | |
285 | % little `\qedrule' symbol is available on its own, by saying |\qedrule|. | |
286 | % This also sets |\qedsymbol| if it's not set already. | |
287 | % \qed | |
288 | % | |
3ba7380e MW |
289 | % \subsection{Punctuation in displays} |
290 | % | |
291 | % It's conventional to follow displayed equations with the necessary | |
292 | % punctuation for them to fit into the surrounding prose. This isn't | |
293 | % universal: Ian Stewart says in the preface to the third edition of his | |
294 | % \emph{Galois Theory}:\footnote{^^A | |
295 | % Chapman \& Hall/CRC Mathematics, 2004; ISBN 1-58488-393-6.} ^^A | |
296 | % \begin{quote} | |
297 | % Along the way I made once change that may raise a few eyebrows. I have | |
298 | % spent much of my career telling students that written mathematics should | |
299 | % have punctuation as well as symbols. If a symbol or a formula would be | |
300 | % followed by a comma if it were replaced by a word or phrase, then it | |
301 | % should be followed by a comma; however strange the formula then looks. | |
302 | % | |
303 | % I still think that punctuation is essential for formulas in the main body | |
304 | % of the text. If the formula is $t^2 + 1$, say, then it should have its | |
305 | % terminating comma. But I have come to the conclusion that eliminating | |
306 | % visual junk from the printed page is more important than punctuatory | |
307 | % pedantry, so that when the same formula is \emph{displayed}, for example | |
308 | % \[ t^2 + 1 \] | |
309 | % then it looks silly if the comma is included, like this, | |
310 | % \[ t^2 + 1 \mpunct{,} \] | |
311 | % and everything is much cleaner and less ambiguous without punctuation. | |
312 | % | |
313 | % Purists will hate this, though many of them would not have noticed had I | |
314 | % not pointed it out here. Until recently, I would have agreed. But I | |
315 | % think it is time we accepted that the act of displaying a formula equips | |
316 | % it with \emph{implicit} (invisible) punctuation. This is the 21st | |
317 | % century, and typography has moved on. | |
318 | % \end{quote}% | |
319 | % | |
320 | % \DescribeMacro\mpunct | |
321 | % I tended to agree with Prof.\ Stewart, even before I read his preface; but | |
322 | % now I'm not so sure, and it's clear that we're in the minority. Therefore, | |
323 | % the command |\mpunct| sets its argument as text, a little distance from | |
324 | % the preceding mathematics. | |
325 | % | |
86f6a31e | 326 | % \begin{ignore} |
327 | % There used to be an eqnarray here, but that's migrated its way into the | |
328 | % \package{mdwtab} package. Maybe the original version, without dependency | |
329 | % on \package{mdwtab} ought to be releasable separately. I'll keep it around | |
330 | % just in case. | |
331 | % | |
332 | % The following is the documentation for the original version. There's an | |
333 | % updated edition in \package{mdwtab}. | |
334 | % \end{ignore} | |
335 | % | |
336 | % \begin{old-eqnarray} | |
337 | % | |
338 | % \subsection{A new \env{eqnarray} environment} | |
339 | % | |
340 | % \LaTeX's built-in \env{eqnarray} is horrible -- it puts far too much space | |
341 | % between the items in the array. This environment is rather nearer to the | |
342 | % \env{amsmath} \env{align} environments, although rather less capable. | |
343 | % | |
344 | % \bigskip | |
345 | % \DescribeEnv{eqnarray} | |
346 | % {\synshorts | |
347 | % \setbox0\hbox{"\\begin{eqnarray}["<preamble>"]" \dots "\\end{eqnarray}"} | |
348 | % \leavevmode \hskip-\parindent \fbox{\box0} | |
349 | % } | |
350 | % \smallskip | |
351 | % | |
352 | % The new version of \env{eqnarray} tries to do everything which you really | |
353 | % want it to. The \synt{preamble} string allows you to define the column | |
354 | % types in a vaguely similar way to the wonderful \env{tabular} environment. | |
355 | % The types provided (and it's easy-ish to add more) are: | |
356 | % | |
357 | % \def\ch{\char`} | |
78cdb9cc | 358 | % \begin{description} \setdescriptionlabel{\normalfont\ttfamily#1} |
86f6a31e | 359 | % \item [r] Right aligned equation |
360 | % \item [c] Centre-aligned equation | |
361 | % \item [l] Left aligned equation | |
362 | % \item [\textrm{\texttt{Tr}, \texttt{Tc} and \texttt{Tl}}] Right, centre and | |
363 | % left aligned text (not maths) | |
364 | % \item [L] Left aligned zero-width equation | |
365 | % \item [x] Centred entire equation | |
366 | % \item [:] Big gap separating sets of equations | |
367 | % \item [q] Quad space | |
368 | % \item [>\ch\{\synt{text}\ch\}] Insert text before column | |
369 | % \item [<\ch\{\synt{text}\ch\}] Insert text after column | |
370 | % \end{description} | |
371 | % | |
372 | % Some others are also defined: don't use them because they do complicated | |
373 | % things which are hard to explain and they aren't much use anyway. | |
374 | % | |
375 | % The default preamble, if you don't supply one of your own, is \lit{rcl}. | |
376 | % Most of the time, \lit{rl} is sufficient, although compatibility is more | |
377 | % important to me. | |
378 | % | |
379 | % By default, there is no space between columns, which makes formul\ae\ in an | |
380 | % \env{eqnarray} environment look just like formul\ae\ typeset on their own, | |
381 | % except that things get aligned in columns. This is where the default | |
382 | % \env{eqnarray} falls down: it leaves |\arraycolsep| space between each | |
383 | % column making the thing look horrible. | |
384 | % | |
385 | % An example would be good here, I think. This one's from exercise 22.9 of | |
386 | % the \textit{\TeX book}. | |
387 | % | |
388 | % \begin{demo}[w]{Simultaneous equations} | |
389 | %\begin{eqnarray}[rcrcrcrl] | |
390 | % 10w & + & 3x & + & 3y & + & 18z & = 1 \\ | |
391 | % 6w & - & 17x & & & - & 5z & = 2 | |
392 | %\end{eqnarray} | |
393 | % \end{demo} | |
394 | % | |
395 | % Choosing a more up-to-date example, here's one demonstrating the \lit{:} | |
396 | % column specifier from the \textit{\LaTeX\ Companion}. | |
397 | % | |
398 | % \begin{demo}[w]{Lots of equations} | |
399 | %\begin{eqnarray}[rl:rl:l] | |
eafdddad | 400 | % V_i &= v_i - q_i v_j, & X_i &= x_i - q_i x_j, & |
86f6a31e | 401 | % U_i = u_i, \qquad \mbox{for $i \ne j$} \label{eq:A} \\ |
402 | % V_j &= v_j, & X_j &= x_j & | |
403 | % U_j u_j + \sum_{i \ne j} q_i u_i. | |
404 | %\end{eqnarray} | |
405 | % \end{demo} | |
406 | % | |
407 | % We can make things more interesting by adding a plain text column. Here we | |
408 | % go: | |
409 | % | |
410 | % \begin{demo}[w]{Plain text column} | |
411 | %\begin{eqnarray}[rlqqTl] | |
412 | % x &= y & by (\ref{eq:A}) \\ | |
413 | % x' &= y' & by definition \\ | |
414 | % x + x' &= y + y' & by Axiom~1 | |
415 | %\end{eqnarray} | |
416 | % \end{demo} | |
417 | % | |
418 | % The new features also mean that you don't need to mess about with | |
419 | % |\lefteqn| any more. This is handled by the \lit{L} column type: | |
420 | % | |
421 | % \begin{demo}{Splitting example} | |
422 | %\begin{eqnarray*}[Ll] | |
423 | % w+x+y+z = \\ | |
4a655c6f | 424 | % & a+b+c+d+e+{} \\ |
86f6a31e | 425 | % & f+g+h+i+j |
426 | %\end{eqnarray*} | |
427 | % \end{demo} | |
428 | % | |
429 | % Finally, just to prove that the spacing's right at last, here's another one | |
430 | % from the \textit{Companion}. | |
431 | % | |
432 | % \begin{demo}{Spacing demonstration} | |
433 | %\begin{equation} | |
434 | % x^2 + y^2 = z^2 | |
435 | %\end{equation} | |
436 | %\begin{eqnarray}[rl] | |
437 | % x^2 + y^2 &= z^2 \\ | |
438 | % y^2 &< z^2 | |
439 | %\end{eqnarray} | |
440 | % \end{demo} | |
441 | % | |
442 | % Well, that was easy enough. Now on to numbering. As you've noticed, the | |
443 | % equations above are numbered. You can use the \env{eqnarray$*$} | |
444 | % environment to turn off the numbering in the whole environment, or say | |
445 | % |\nonumber| on a line to suppress numbering of that one in particular. | |
446 | % More excitingly, you can say \syntax{"\\nonumber["<text>"]"} to choose | |
447 | % what text to display. | |
448 | % | |
449 | % A note for cheats: you can use the sparkly new \env{eqnarray} for simple | |
450 | % equations simply by specifying \lit{x} as the column description. Who | |
451 | % needs \AmSTeX? |;-)| | |
452 | % | |
453 | % \end{old-eqnarray} | |
454 | % | |
455 | % \implementation | |
456 | % | |
457 | % \section{Implementation} | |
458 | % | |
459 | % This isn't really complicated (honest) although it is a lot hairier than I | |
460 | % think it ought to be. | |
461 | % | |
462 | % \begin{macrocode} | |
463 | %<*package> | |
4a655c6f | 464 | \RequirePackage{amssymb} |
465 | \RequirePackage{mdwkey} | |
86f6a31e | 466 | % \end{macrocode} |
467 | % | |
468 | % \subsection{Square roots} | |
469 | % | |
470 | % \subsubsection{Where is the square root sign?} | |
471 | % | |
472 | % \LaTeX\ hides the square root sign away somewhere without telling anyone | |
473 | % where it is. I extract it forcibly by peeking inside the |\sqrtsign| macro | |
474 | % and scrutinising the contents. Here we go: prepare for yukkiness. | |
475 | % | |
476 | % \begin{macrocode} | |
477 | \newcount\sq@sqrt \begingroup \catcode`\|0 \catcode`\\12 | |
478 | |def|sq@readrad#1"#2\#3|relax{|global|sq@sqrt"#2|relax} | |
479 | |expandafter|sq@readrad|meaning|sqrtsign|relax |endgroup | |
480 | \def\sq@delim{\delimiter\sq@sqrt\relax} | |
481 | % \end{macrocode} | |
482 | % | |
483 | % \subsubsection{Drawing fake square root signs} | |
484 | % | |
485 | % \TeX\ absolutely insists on drawing square root signs with a vinculum over | |
486 | % the top. In order to get the same effect, we have to attempt to emulate | |
487 | % \TeX's behaviour. | |
488 | % | |
489 | % \begin{macro}{\sqrtdel} | |
490 | % | |
491 | % This does the main job of typesetting a vinculum-free radical.\footnote{^^A | |
492 | % Note for chemists: this is nothing to do with short-lived things which | |
493 | % don't have their normal numbers of electrons. And it won't reduce the | |
494 | % appearance of wrinkles either.} | |
495 | % It's more or less a duplicate of what \TeX\ does internally, so it might be | |
496 | % a good plan to have a copy of Appendix~G open while you examine this. | |
497 | % | |
498 | % We start off by using |\mathpalette| to help decide how big things should | |
499 | % be. | |
500 | % | |
501 | % \begin{macrocode} | |
502 | \def\sqrtdel{\mathpalette\sqrtdel@i} | |
503 | % \end{macrocode} | |
504 | % | |
505 | % Read the contents of the radical into a box, so we can measure it. | |
506 | % | |
507 | % \begin{macrocode} | |
508 | \def\sqrtdel@i#1#2{% | |
509 | \setbox\z@\hbox{$\m@th#1#2$}% %%% Bzzzt -- uncramps the mathstyle | |
510 | % \end{macrocode} | |
511 | % | |
512 | % Now try and sort out the values needed in this calculation. We'll assume | |
513 | % that $\xi_8$ is 0.6\,pt, the way it usually is. Next try to work out the | |
514 | % value of $\varphi$. | |
515 | % | |
516 | % \begin{macrocode} | |
517 | \ifx#1\displaystyle% | |
518 | \@tempdima1ex% | |
519 | \else% | |
520 | \@tempdima.6\p@% | |
521 | \fi% | |
522 | % \end{macrocode} | |
523 | % | |
524 | % That was easy. Now for $\psi$. | |
525 | % | |
526 | % \begin{macrocode} | |
527 | \@tempdimb.6\p@% | |
528 | \advance\@tempdimb.25\@tempdima% | |
529 | % \end{macrocode} | |
530 | % | |
531 | % Build the `delimiter' in a box of height $h(x)+d(x)+\psi+\xi_8$, as | |
532 | % requested. Box~2 will do well for this purpose. | |
533 | % | |
534 | % \begin{macrocode} | |
535 | \dimen@.6\p@% | |
536 | \advance\dimen@\@tempdimb% | |
537 | \advance\dimen@\ht\z@% | |
538 | \advance\dimen@\dp\z@% | |
539 | \setbox\tw@\hbox{% | |
540 | $\left\sq@delim\vcenter to\dimen@{}\right.\n@space$% | |
541 | }% | |
542 | % \end{macrocode} | |
543 | % | |
544 | % Now we need to do some more calculating (don't you hate it?). As far as | |
545 | % Appendix~G is concerned, $\theta=h(y)=0$, because we want no rule over the | |
e8e9e5d8 | 546 | % top. |
86f6a31e | 547 | % |
548 | % \begin{macrocode} | |
549 | \@tempdima\ht\tw@% | |
550 | \advance\@tempdima\dp\tw@% | |
551 | \advance\@tempdima-\ht\z@% | |
552 | \advance\@tempdima-\dp\z@% | |
553 | \ifdim\@tempdima>\@tempdimb% | |
554 | \advance\@tempdima\@tempdimb% | |
555 | \@tempdimb.5\@tempdima% | |
556 | \fi% | |
557 | % \end{macrocode} | |
558 | % | |
559 | % Work out how high to raise the radical symbol. Remember that Appendix~G | |
560 | % thinks that the box has a very small height, although this is untrue here. | |
561 | % | |
562 | % \begin{macrocode} | |
563 | \@tempdima\ht\z@% | |
564 | \advance\@tempdima\@tempdimb% | |
565 | \advance\@tempdima-\ht\tw@% | |
566 | % \end{macrocode} | |
567 | % | |
568 | % Build the output (finally). The brace group is there to turn the output | |
569 | % into a mathord, one of the few times that this is actually desirable. | |
570 | % | |
571 | % \begin{macrocode} | |
572 | {\raise\@tempdima\box\tw@\vbox{\kern\@tempdimb\box\z@}}% | |
573 | } | |
574 | % \end{macrocode} | |
575 | % | |
576 | % \end{macro} | |
577 | % | |
578 | % \subsubsection{The new square root command} | |
579 | % | |
580 | % This is where we reimplement all the square root stuff. Most of this stuff | |
581 | % comes from the \PlainTeX\ macros, although some is influenced by \AmSTeX\ | |
582 | % and \LaTeXe, and some is original. I've tried to make the spacing vaguely | |
583 | % automatic, so although it's not configurable like \AmSTeX's version, the | |
584 | % output should look nice more of the time. Maybe. | |
585 | % | |
586 | % \begin{macro}{\sqrt} | |
587 | % | |
588 | % \LaTeX\ says this must be robust, so we make it robust. The first thing to | |
589 | % do is to see if there's a star and pass the appropriate squareroot-drawing | |
590 | % command on to the rest of the code. | |
591 | % | |
592 | % \begin{macrocode} | |
593 | \DeclareRobustCommand\sqrt{\@ifstar{\sqrt@i\sqrtdel}{\sqrt@i\sqrtsign}} | |
594 | % \end{macrocode} | |
595 | % | |
596 | % Now we can sort out an optional argument to be displayed on the root. | |
597 | % | |
598 | % \begin{macrocode} | |
599 | \def\sqrt@i#1{\@ifnextchar[{\sqrt@ii{#1}}{\sqrt@iv{#1}}} | |
600 | % \end{macrocode} | |
601 | % | |
602 | % Stages~2 and~3 below are essentially equivalents of \PlainTeX's | |
603 | % |\root|\dots|\of| and |\r@@t|. Here we also find the first wrinkle: the | |
604 | % |\rootbox| used to store the number is spaced out on the left if necessary. | |
605 | % There's a backspace after the end so that the root can slip underneath, and | |
606 | % everything works out nicely. Unfortunately size is fixed here, although | |
607 | % doesn't actually seem to matter. | |
608 | % | |
609 | % \begin{macrocode} | |
610 | \def\sqrt@ii#1[#2]{% | |
611 | \setbox\rootbox\hbox{$\m@th\scriptscriptstyle{#2}$}% | |
612 | \ifdim\wd\rootbox<6\p@% | |
613 | \setbox\rootbox\hb@xt@6\p@{\hfil\unhbox\rootbox}% | |
614 | \fi% | |
615 | \mathpalette{\sqrt@iii{#1}}% | |
616 | } | |
617 | % \end{macrocode} | |
618 | % | |
619 | % Now we can actually build everything. Note that the root is raised by its | |
620 | % depth -- this prevents a common problem with letters with descenders. | |
621 | % | |
622 | % \begin{macrocode} | |
623 | \def\sqrt@iii#1#2#3{% | |
624 | \setbox\z@\hbox{$\m@th#2#1{#3}$}% | |
625 | \dimen@\ht\z@% | |
626 | \advance\dimen@-\dp\z@% | |
627 | \dimen@.6\dimen@% | |
628 | \advance\dimen@\dp\rootbox% | |
629 | \mkern-3mu% | |
630 | \raise\dimen@\copy\rootbox% | |
631 | \mkern-10mu% | |
632 | \box\z@% | |
633 | } | |
634 | % \end{macrocode} | |
635 | % | |
636 | % Finally handle a non-numbered root. We read the rooted text in as an | |
637 | % argument, to stop problems when people omit the braces. (\AmSTeX\ does | |
638 | % this too.) | |
639 | % | |
640 | % \begin{macrocode} | |
641 | \def\sqrt@iv#1#2{#1{#2}} | |
642 | % \end{macrocode} | |
643 | % | |
644 | % \end{macro} | |
645 | % | |
646 | % \begin{macro}{\root} | |
647 | % | |
648 | % We also re-implement \PlainTeX's |\root| command, just in case someone uses | |
649 | % it, and supply a star-variant. This is all very trivial. | |
650 | % | |
651 | % \begin{macrocode} | |
652 | \def\root{\@ifstar{\root@i\sqrtdel}{\root@i\sqrtsign}} | |
653 | \def\root@i#1#2\of{\sqrt@ii{#1}[#2]} | |
654 | % \end{macrocode} | |
655 | % | |
656 | % \end{macro} | |
657 | % | |
658 | % \subsection{Modular programming} | |
659 | % | |
660 | % \begin{macro}{\pmod} | |
661 | % | |
662 | % Do some hacking if not |\ifouter|. | |
663 | % | |
664 | % \begin{macrocode} | |
665 | \def\pmod#1{% | |
666 | \ifinner\;\else\allowbreak\mkern18mu\fi% | |
667 | ({\operator@font mod}\,\,#1)% | |
668 | } | |
669 | % \end{macrocode} | |
670 | % | |
671 | % \end{macro} | |
672 | % | |
673 | % \subsection{Some magic new maths characters} | |
674 | % | |
675 | % \begin{macro}{\bitor} | |
676 | % \begin{macro}{\bitand} | |
677 | % \begin{macro}{\dblor} | |
678 | % \begin{macro}{\dbland} | |
679 | % \begin{macro}{\xor} | |
680 | % \begin{macro}{\lor} | |
681 | % \begin{macro}{\ror} | |
682 | % \begin{macro}{\lsl} | |
683 | % \begin{macro}{\lsr} | |
684 | % | |
685 | % The new boolean operators. | |
686 | % | |
687 | % \begin{macrocode} | |
688 | \DeclareMathSymbol{&}{\mathbin}{operators}{`\&} | |
689 | \DeclareMathSymbol{\bitand}{\mathbin}{operators}{`\&} | |
690 | \def\bitor{\mathbin\mid} | |
691 | \def\dblor{\mathbin{\mid\mid}} | |
692 | \def\dbland{\mathbin{\mathrel\bitand\mathrel\bitand}} | |
693 | \let\xor\oplus | |
694 | \def\lsl{\mathbin{<\!\!<}} | |
695 | \def\lsr{\mathbin{>\!\!>}} | |
696 | \def\rol{\mathbin{<\!\!<\!\!<}} | |
697 | \def\ror{\mathbin{>\!\!>\!\!>}} | |
698 | \AtBeginDocument{\ifx\lll\@@undefined\else | |
699 | \def\lsl{\mathbin{\ll}} | |
700 | \def\lsr{\mathbin{\gg}} | |
701 | \def\rol{\mathbin{\lll}} | |
702 | \def\ror{\mathbin{\ggg}} | |
703 | \fi} | |
704 | % \end{macrocode} | |
705 | % | |
706 | % \end{macro} | |
707 | % \end{macro} | |
708 | % \end{macro} | |
709 | % \end{macro} | |
710 | % \end{macro} | |
711 | % \end{macro} | |
712 | % \end{macro} | |
713 | % \end{macro} | |
714 | % \end{macro} | |
715 | % | |
716 | % \begin{macro}{\cat} | |
717 | % \begin{macro}{\compose} | |
718 | % \begin{macro}{\implies} | |
719 | % \begin{macro}{\vect} | |
720 | % \begin{macro}{\d} | |
721 | % \begin{macro}{\jacobi} | |
722 | % | |
723 | % A mixed bag of stuff. | |
724 | % | |
725 | % \begin{macrocode} | |
726 | \def\cat{\mathbin{\|}} | |
727 | \let\compose\circ | |
728 | \def\implies{\Rightarrow} | |
729 | \def\vect#1{\mathord{\mathbf{#1}}} | |
4a655c6f | 730 | \def\d{% |
731 | \ifmmode\mathord{\operator@font d}% | |
732 | \else\expandafter\a\expandafter d\fi% | |
733 | } | |
86f6a31e | 734 | \def\jacobi#1#2{{{#1}\overwithdelims()#2}} |
735 | % \end{macrocode} | |
736 | % | |
737 | % \end{macro} | |
738 | % \end{macro} | |
739 | % \end{macro} | |
740 | % \end{macro} | |
741 | % \end{macro} | |
742 | % \end{macro} | |
743 | % | |
744 | % \begin{macro}{\statclose} | |
745 | % \begin{macro}{\compind} | |
746 | % | |
747 | % Fancy new relations for probability distributions. | |
748 | % | |
749 | % \begin{macrocode} | |
750 | \def\statclose{\mathrel{\mathop{=}\limits^{\scriptscriptstyle s}}} | |
751 | \def\compind{\mathrel{\mathop{\approx}\limits^{\scriptscriptstyle c}}} | |
752 | % \end{macrocode} | |
753 | % | |
754 | % \end{macro} | |
755 | % \end{macro} | |
756 | % | |
757 | % \begin{macro}{\keys} | |
758 | % \begin{macro}{\dom} | |
759 | % \begin{macro}{\ran} | |
760 | % \begin{macro}{\supp} | |
761 | % \begin{macro}{\lcm} | |
4a655c6f | 762 | % \begin{macro}{\poly} |
763 | % \begin{macro}{\negl} | |
764 | % \begin{macro}{\ord} | |
86f6a31e | 765 | % |
766 | % And the new operator names. | |
767 | % | |
768 | % \begin{macrocode} | |
769 | \def\keys{\mathop{\operator@font keys}\nolimits} | |
770 | \def\dom{\mathop{\operator@font dom}\nolimits} | |
771 | \def\ran{\mathop{\operator@font ran}\nolimits} | |
772 | \def\supp{\mathop{\operator@font supp}\nolimits} | |
773 | \def\lcm{\mathop{\operator@font lcm}\nolimits} | |
4a655c6f | 774 | \def\poly{\mathop{\operator@font poly}\nolimits} |
775 | \def\negl{\mathop{\operator@font negl}\nolimits} | |
776 | \def\ord{\mathop{\operator@font ord}\nolimits} | |
86f6a31e | 777 | % \end{macrocode} |
778 | % | |
779 | % \end{macro} | |
780 | % \end{macro} | |
781 | % \end{macro} | |
782 | % \end{macro} | |
783 | % \end{macro} | |
4a655c6f | 784 | % \end{macro} |
785 | % \end{macro} | |
786 | % \end{macro} | |
787 | % | |
788 | % \subsection{Fractions} | |
789 | % | |
790 | % \begin{macro}{\@frac@parse} | |
791 | % | |
792 | % \syntax{"\\@frac@parse{"<stuff>"}{"<frac-params>"}"} -- run \<stuff> | |
793 | % passing it three arguments: an infix fraction-making command, the `outer' | |
794 | % style, and the `inner' style. | |
795 | % | |
796 | % This is rather tricky. We clear a load of parameters, parse the parameter | |
797 | % list, and then build a token list containing the right stuff. Without the | |
798 | % token list fiddling, we end up expanding things at the wrong times -- for | |
799 | % example, |\{| expands to something terribly unpleasant in a document | |
800 | % preamble. | |
801 | % | |
802 | % All of the nastiness is contained in a group. | |
803 | % | |
804 | % \begin{macrocode} | |
805 | \def\@frac@parse#1#2{% | |
806 | \begingroup% | |
807 | \let\@wd\@empty\def\@ldel{.}\def\@rdel{.}% | |
808 | \def\@op{over}\let\@dim\@empty\@tempswafalse% | |
809 | \let\@is\@empty\let\@os\@empty% | |
810 | \mkparse{mdwmath:frac}{#2}% | |
811 | \toks\tw@{\endgroup#1}% | |
812 | \toks@\expandafter{\csname @@\@op\@wd\endcsname}% | |
813 | \if@tempswa% | |
814 | \toks@\expandafter{\the\expandafter\toks@\@ldel}% | |
815 | \toks@\expandafter{\the\expandafter\toks@\@rdel}% | |
816 | \fi% | |
817 | \expandafter\toks@\expandafter{\the\expandafter\toks@\@dim}% | |
818 | \toks@\expandafter{\the\toks\expandafter\tw@\expandafter{\the\toks@}} | |
819 | \toks@\expandafter{\the\expandafter\toks@\expandafter{\@os}} | |
820 | \toks@\expandafter{\the\expandafter\toks@\expandafter{\@is}} | |
821 | \the\toks@% | |
822 | } | |
823 | % \end{macrocode} | |
824 | % | |
825 | % The keyword definitions are relatively straightforward now. The error | |
826 | % handling for \textsf{style} and \textsf{innerstyle} could do with | |
827 | % improvement. | |
828 | % | |
829 | % \begin{macrocode} | |
830 | \def\@frac@del#1#2{\def\@wd{withdelims}\@tempswatrue\def#1{#2}} | |
831 | \mkdef{mdwmath:frac}{leftdelim}{\@frac@del\@ldel{#1}} | |
832 | \mkdef{mdwmath:frac}{rightdelim}{\@frac@del\@rdel{#1}} | |
833 | \mkdef{mdwmath:frac}{nodelims}*{\let\@wd\@empty\@tempswafalse} | |
834 | \mkdef{mdwmath:frac}{line}{% | |
835 | \def\@op{above}\setlength\dimen@{#1}\edef\@dim{\the\dimen@\space}% | |
836 | } | |
837 | \mkdef{mdwmath:frac}{line}*{\def\@op{over}\let\@dim\@empty} | |
838 | \mkdef{mdwmath:frac}{noline}*{\def\@op{atop}\let\@dim\@empty} | |
839 | \def\@frac@style#1#2{% | |
840 | \ifx\q@delim#2\q@delim\let#1\@empty% | |
841 | \else% | |
842 | \expandafter\ifx\csname #2style\endcsname\relax% | |
843 | \PackageError{mdwmath}{Bad maths style `#2'}\@ehc% | |
844 | \else% | |
845 | \edef#1{\csname#2style\endcsname}% | |
846 | \fi% | |
847 | \fi% | |
848 | } | |
849 | \mkdef{mdwmath:frac}{style}[]{\@frac@style\@os{#1}} | |
850 | \mkdef{mdwmath:frac}{innerstyle}[]{\@frac@style\@is{#1}} | |
851 | % \end{macrocode} | |
852 | % | |
853 | % \end{macro} | |
854 | % | |
855 | % \begin{macro}{\fracdef} | |
856 | % | |
857 | % Here's where the rest of the pain is. We do a preliminary parse of the | |
858 | % parameters and `compile' the result into the output macro. If there's no | |
859 | % optional argument, then we don't need to do any really tedious formatting | |
860 | % at the point of use. | |
861 | % | |
862 | % \begin{macrocode} | |
863 | \def\fracdef#1#2{\@frac@parse{\fracdef@i{#1}{#2}}{#2}} | |
864 | \def\fracdef@i#1#2#3#4#5{\def#1{\@frac@do{#2}{#3}{#4}{#5}}} | |
865 | \def\@frac@do#1#2#3#4{% | |
866 | \@ifnextchar[{\@frac@complex{#1}}{\@frac@simple{#2}{#3}{#4}}% | |
867 | } | |
868 | \def\@frac@complex#1[#2]{\@frac@parse\@frac@simple{#1,#2}} | |
869 | \def\@frac@simple#1#2#3#4#5{{#2{{#3#4}#1{#3#5}}}} | |
870 | % \end{macrocode} | |
871 | % | |
872 | % \end{macro} | |
873 | % | |
874 | % \begin{macro}{\frac@fix} | |
875 | % \begin{macro}{\@@over} | |
876 | % \begin{macro}{\@@atop} | |
877 | % \begin{macro}{\@@above} | |
878 | % \begin{macro}{\@@overwithdelims} | |
879 | % \begin{macro}{\@@atopwithdelims} | |
880 | % \begin{macro}{\@@abovewithdelims} | |
881 | % | |
882 | % Finally, we need to fix up |\@@over| and friends. Maybe \package{amsmath} | |
883 | % has hidden the commands away somewhere unhelpful. If not, we make the | |
884 | % requisite copies. | |
885 | % | |
886 | % \begin{macrocode} | |
887 | \def\q@delim{\q@delim} | |
888 | \def\frac@fix#1{\expandafter\frac@fix@i\string#1\q@delim} | |
889 | \def\frac@fix@i#1#2\q@delim{\frac@fix@ii{#2}\frac@fix@ii{#2withdelims}} | |
890 | \def\frac@fix@ii#1{% | |
891 | \expandafter\ifx\csname @@#1\endcsname\relax% | |
892 | \expandafter\let\csname @@#1\expandafter\endcsname\csname#1\endcsname% | |
893 | \fi% | |
894 | } | |
895 | \frac@fix\over \frac@fix\atop \frac@fix\above | |
896 | % \end{macrocode} | |
897 | % | |
898 | % \end{macro} | |
899 | % \end{macro} | |
900 | % \end{macro} | |
901 | % \end{macro} | |
902 | % \end{macro} | |
903 | % \end{macro} | |
904 | % \end{macro} | |
905 | % | |
906 | % \begin{macro}{\frac} | |
907 | % \begin{macro}{\binom} | |
908 | % \begin{macro}{\jacobi} | |
909 | % | |
910 | % And finally, we define the fraction-making commands. | |
911 | % | |
912 | % \begin{macrocode} | |
913 | \fracdef\frac{nodelims, line} | |
914 | \fracdef\binom{leftdelim = (, rightdelim = ), noline} | |
915 | \fracdef\jacobi{leftdelim = (, rightdelim = ), line} | |
916 | % \end{macrocode} | |
917 | % | |
918 | % \end{macro} | |
919 | % \end{macro} | |
920 | % \end{macro} | |
86f6a31e | 921 | % |
922 | % \subsection{Blackboard bold stuff} | |
923 | % | |
924 | % \begin{macro}{\Z} | |
925 | % \begin{macro}{\Q} | |
926 | % \begin{macro}{\R} | |
927 | % \begin{macro}{\C} | |
928 | % \begin{macro}{\N} | |
929 | % \begin{macro}{\F} | |
930 | % \begin{macro}{\powerset} | |
4a655c6f | 931 | % \begin{macro}{\gf} |
86f6a31e | 932 | % |
933 | % First of all, the signs. | |
934 | % | |
935 | % \begin{macrocode} | |
936 | \def\Z{\mathbb{Z}} | |
937 | \def\Q{\mathbb{Q}} | |
938 | \def\R{\mathbb{R}} | |
939 | \def\C{\mathbb{C}} | |
940 | \def\N{\mathbb{N}} | |
941 | \def\F{\mathbb{F}} | |
942 | \def\powerset{\mathbb{P}} | |
4a655c6f | 943 | \def\gf#1{\F_{#1}} |
944 | %\def\gf#1{\mathrm{GF}({#1})} | |
86f6a31e | 945 | % \end{macrocode} |
946 | % | |
947 | % \end{macro} | |
948 | % \end{macro} | |
949 | % \end{macro} | |
950 | % \end{macro} | |
951 | % \end{macro} | |
952 | % \end{macro} | |
953 | % \end{macro} | |
4a655c6f | 954 | % \end{macro} |
86f6a31e | 955 | % |
956 | % And now, define |\mathbb| if it's not there already. | |
957 | % | |
958 | % \begin{macrocode} | |
959 | \AtBeginDocument{\ifx\mathbb\@@undefined\let\mathbb\mathbf\fi} | |
960 | % \end{macrocode} | |
961 | % | |
962 | % \subsection{Biggles} | |
963 | % | |
964 | % Now for some user-controlled delimiter sizing. The standard bigness of | |
965 | % plain \TeX's delimiters are all right, but it's a little limiting. | |
966 | % | |
967 | % The biggness of delimiters is based on the size of the current |\strut|, | |
968 | % which \LaTeX\ keeps up to date all the time. This will make the various | |
969 | % delimiters grow in proportion when the text gets bigger. Actually, I'm | |
970 | % not sure that this is exactly right -- maybe it should be nonlinear, | |
971 | % | |
972 | % \begin{macro}{\bbigg} | |
973 | % \begin{macro}{\bbiggl} | |
974 | % \begin{macro}{\bbiggr} | |
975 | % \begin{macro}{\bbiggm} | |
976 | % | |
977 | % This is where the bigness is done. This is more similar to the plain \TeX\ | |
978 | % big delimiter stuff than to the \package{amsmath} stuff, although there's | |
979 | % not really a lot of difference. | |
980 | % | |
981 | % The two arguments are a multiplier for the delimiter size, and a small | |
982 | % increment applied \emph{before} the multiplication (which is optional). | |
983 | % | |
984 | % This is actually a front for a low-level interface which can be called | |
985 | % directly for efficiency. | |
986 | % | |
987 | % \begin{macrocode} | |
988 | \def\bbigg{\@bbigg\mathord} \def\bbiggl{\@bbigg\mathopen} | |
989 | \def\bbiggr{\@bbigg\mathclose} \def\bbiggm{\@bbigg\mathrel} | |
990 | % \end{macrocode} | |
991 | % | |
992 | % \end{macro} | |
993 | % \end{macro} | |
994 | % \end{macro} | |
995 | % \end{macro} | |
996 | % | |
997 | % \begin{macro}{\@bbigg} | |
998 | % | |
999 | % This is an optional argument parser providing a front end for the main | |
1000 | % macro |\bbigg@|. | |
1001 | % | |
1002 | % \begin{macrocode} | |
1003 | \def\@bbigg#1{\@ifnextchar[{\@bigg@i{#1}}{\@bigg@i{#1}[\z@]}} | |
1004 | \def\@bigg@i#1[#2]#3#4{#1{\bbigg@{#2}{#3}{#4}}} | |
1005 | % \end{macrocode} | |
1006 | % | |
1007 | % \end{macro} | |
1008 | % | |
1009 | % \begin{macro}{\bbigg@} | |
1010 | % | |
1011 | % This is it, at last. The arguments are as described above: an addition | |
1012 | % to be made to the strut height, and a multiplier. Oh, and the delimiter, | |
1013 | % of course. | |
1014 | % | |
1015 | % This is a bit messy. The smallest `big' delimiter, |\big|, is the same | |
1016 | % height as the current strut box. Other delimiters are~$1\frac12$, $2$ | |
1017 | % and~$2\frac12$ times this height. I'll set the height of the delimiter by | |
1018 | % putting in a |\vcenter| of the appropriate size. | |
1019 | % | |
1020 | % Given an extra height~$x$, a multiplication factor~$f$ and a strut | |
1021 | % height~$h$ and depth~$d$, I'll create a vcenter with total height | |
1022 | % $f(h+d+x)$. Easy, isn't it? | |
1023 | % | |
1024 | % \begin{macrocode} | |
1025 | \def\bbigg@#1#2#3{% | |
1026 | {\hbox{$% | |
1027 | \dimen@\ht\strutbox\advance\dimen@\dp\strutbox% | |
1028 | \advance\dimen@#1% | |
1029 | \dimen@#2\dimen@% | |
1030 | \left#3\vcenter to\dimen@{}\right.\n@space% | |
1031 | $}}% | |
1032 | } | |
1033 | % \end{macrocode} | |
1034 | % | |
1035 | % \end{macro} | |
1036 | % | |
1037 | % \begin{macro}{\big} | |
1038 | % \begin{macro}{\Big} | |
1039 | % \begin{macro}{\bigg} | |
1040 | % \begin{macro}{\Bigg} | |
1041 | % | |
1042 | % Now for the easy macros. | |
1043 | % | |
1044 | % \begin{macrocode} | |
1045 | \def\big{\bbigg@\z@\@ne} | |
1046 | \def\Big{\bbigg@\z@{1.5}} | |
1047 | \def\bigg{\bbigg@\z@\tw@} | |
1048 | \def\Bigg{\bbigg@\z@{2.5}} | |
1049 | % \end{macrocode} | |
1050 | % | |
1051 | % \end{macro} | |
1052 | % \end{macro} | |
1053 | % \end{macro} | |
1054 | % \end{macro} | |
1055 | % | |
1056 | % \subsection{The `QED' symbol} | |
1057 | % | |
1058 | % \begin{macro}{\qed} | |
1059 | % \begin{macro}{\qedrule} | |
1060 | % \begin{macro}{\qedsymbol} | |
1061 | % | |
1062 | % This is fairly simple. Just be careful will the glue and penalties. The | |
1063 | % size of the little box is based on the current font size. | |
1064 | % | |
1065 | % The horizontal list constructed by the macro is like this: | |
1066 | % | |
1067 | % \begin{itemize} | |
1068 | % \item A |\quad| of space. This might get eaten if there's a break here or | |
1069 | % before. That's OK, though. | |
1070 | % \item An empty box, to break a run of discardable items. | |
1071 | % \item A |\penalty 10000| to ensure that the spacing glue isn't discarded. | |
1072 | % \item |\hfill| glue to push the little rule to the end of the line. | |
1073 | % \item A little square rule `\qedrule', with some small kerns around it. | |
1074 | % \item A glue item to counter the effect of glue added at the paragraph | |
e8e9e5d8 | 1075 | % boundary. |
86f6a31e | 1076 | % \end{itemize} |
1077 | % | |
4a655c6f | 1078 | % The vertical mode case is simpler, but less universal. It copes with |
1079 | % relatively simple cases only. | |
1080 | % | |
86f6a31e | 1081 | % A |\qed| commend ends the paragraph. |
1082 | % | |
1083 | % \begin{macrocode} | |
4a655c6f | 1084 | \def\qed{% |
1085 | \ifvmode% | |
1086 | \unskip% | |
1087 | \setbox\z@\hb@xt@\linewidth{\hfil\strut\qedsymbol}% | |
1088 | \prevdepth-\@m\p@% | |
1089 | \ifdim\prevdepth>\dp\strutbox% | |
1090 | \dimen@\prevdepth\advance\dimen@-\dp\strutbox% | |
1091 | \kern-\dimen@% | |
1092 | \fi% | |
1093 | \penalty\@M\vskip-\baselineskip\box\z@% | |
1094 | \else% | |
1095 | \unskip% | |
1096 | \penalty\@M\hfill% | |
1097 | \hbox{}\penalty200\quad% | |
1098 | \hbox{}\penalty\@M\hfill\qedsymbol\hskip-\parfillskip\par% | |
1099 | \fi% | |
86f6a31e | 1100 | } |
1101 | \def\qedrule{{% | |
1102 | \dimen@\ht\strutbox% | |
4a655c6f | 1103 | \advance\dimen@\dp\strutbox% |
86f6a31e | 1104 | \dimen@ii1ex% |
1105 | \advance\dimen@-\dimen@ii% | |
1106 | \divide\dimen@\tw@% | |
1107 | \advance\dimen@-\dp\strutbox% | |
1108 | \advance\dimen@\dimen@ii% | |
1109 | \advance\dimen@ii-\dimen@% | |
1110 | \kern\p@% | |
1111 | \vrule\@width1ex\@height\dimen@\@depth\dimen@ii% | |
1112 | \kern\p@% | |
1113 | }} | |
1114 | \providecommand\qedsymbol{\qedrule} | |
1115 | % \end{macrocode} | |
1116 | % | |
1117 | % \end{macro} | |
1118 | % \end{macro} | |
1119 | % \end{macro} | |
1120 | % | |
3ba7380e MW |
1121 | % \subsection{Punctuation in displays} |
1122 | % | |
1123 | % \begin{macro}{\mpunct} | |
1124 | % | |
1125 | % This is actually a little more subtle than you'd expect. If the | |
1126 | % \package{amstext} package is loaded, or something else has defined the | |
1127 | % |\text| command, then we should use that; otherwise, just drop a box in and | |
1128 | % hope for the best. | |
1129 | % | |
1130 | % \begin{macrocode} | |
1131 | \def\mpunct#1{% | |
1132 | \,% | |
1133 | \ifx\text\@@undefined\hbox% | |
1134 | \else\expandafter\text\fi% | |
1135 | {#1}% | |
1136 | } | |
1137 | % \end{macrocode} | |
1138 | % | |
1139 | %\end{macro} | |
1140 | % | |
86f6a31e | 1141 | % \begin{ignore} |
1142 | % The following is the original definition of the enhanced eqnarray | |
1143 | % environment. It's not supported, although if you can figure out how to | |
1144 | % extract it, it's all yours. | |
1145 | % \end{ignore} | |
1146 | % | |
1147 | % \begin{old-eqnarray} | |
1148 | % | |
1149 | % \subsection{The sparkly new \env{eqnarray}} | |
1150 | % | |
1151 | % Start off by writing a different package. | |
1152 | % | |
1153 | % \begin{macrocode} | |
1154 | %</package> | |
1155 | %<*oldeqnarray> | |
1156 | % \end{macrocode} | |
1157 | % | |
1158 | % \subsubsection{Options handling} | |
1159 | % | |
1160 | % We need to be able to cope with \textsf{fleqn} and \textsf{leqno} options. | |
1161 | % This will adjust our magic modified \env{eqnarray} environment | |
1162 | % appropriately. | |
1163 | % | |
1164 | % \begin{macrocode} | |
1165 | \newif\if@fleqn | |
1166 | \newif\if@leqno | |
1167 | \DeclareOption{fleqn}{\@fleqntrue} | |
1168 | \DeclareOption{leqno}{\@leqnotrue} | |
1169 | \ProcessOptions | |
1170 | % \end{macrocode} | |
1171 | % | |
1172 | % This is all really different to the \LaTeX\ version. I've looked at the | |
1173 | % various \env{tabular} implementations, the original \env{eqnarray} and the | |
1174 | % \textit{\TeX book} to see how best to do this, and then went my own way. | |
1175 | % If it doesn't work it's all my fault. | |
1176 | % | |
1177 | % \subsubsection{Some useful registers} | |
1178 | % | |
1179 | % The old \LaTeX\ version puts the equation numbers in by keeping a count of | |
1180 | % where it is in the alignment. Since I don't know how may columns there are | |
1181 | % going to be, I'll just use a switch in the preamble to tell me to stop | |
1182 | % tabbing. | |
1183 | % | |
1184 | % \begin{macrocode} | |
1185 | \newif\if@eqalast | |
1186 | % \end{macrocode} | |
1187 | % | |
1188 | % Now define some useful length parameters. First allocate them: | |
1189 | % | |
1190 | % \begin{macrocode} | |
1191 | \newskip\eqaopenskip | |
1192 | \newskip\eqacloseskip | |
1193 | \newskip\eqacolskip | |
1194 | \newskip\eqainskip | |
1195 | % \end{macrocode} | |
1196 | % | |
1197 | % Now assign some default values. Users can play with these if they really | |
1198 | % want although I can't see the point myself. | |
1199 | % | |
1200 | % \begin{macrocode} | |
1201 | \if@fleqn | |
1202 | \AtBeginDocument{\eqaopenskip\leftmargini} | |
1203 | \else | |
1204 | \eqaopenskip\@centering | |
1205 | \fi | |
1206 | \eqacloseskip\@centering | |
1207 | \eqacolskip\@centering | |
1208 | \eqainskip\z@ | |
1209 | % \end{macrocode} | |
1210 | % | |
1211 | % We allow the user to play with the style if this is really wanted. I dunno | |
1212 | % why, really. Maybe someone wants very small alignments. | |
1213 | % | |
1214 | % \begin{macrocode} | |
1215 | \let\eqa@style\displaystyle | |
1216 | % \end{macrocode} | |
1217 | % | |
1218 | % \subsubsection{The main environments} | |
1219 | % | |
1220 | % We define the toplevel commands here. They just add in default arguments | |
1221 | % and then call |\@eqnarray| with a preamble string. The only difference is | |
1222 | % the last column they add in -- \env{eqnarray$*$} throws away the last | |
1223 | % column by sticking it in box~0. (I used to |\@gobble| it but that caused | |
1224 | % the |\cr| to be lost.) | |
1225 | % | |
1226 | % \begin{macrocode} | |
1227 | \def\eqnarray{\@ifnextchar[\eqnarray@i{\eqnarray@i[rcl]}} | |
1228 | \def\eqnarray@i[#1]{% | |
1229 | \@eqnarray{#1!{\hb@xt@\z@{\hss##}\tabskip\z@}} | |
1230 | } | |
1231 | \@namedef{eqnarray*}{\@ifnextchar[\eqnarray@s@i{\eqnarray@s@i[rcl]}} | |
1232 | \def\eqnarray@s@i[#1]{% | |
1233 | \@eqnarray{#1!{\nonumber\setbox\z@\hbox{##}\tabskip\z@}}% | |
1234 | } | |
1235 | % \end{macrocode} | |
1236 | % | |
1237 | % \subsubsection{Set up the initial display} | |
1238 | % | |
1239 | % \begin{macro}{\@eqnarray} | |
1240 | % | |
1241 | % The |\@eqnarray| command does most of the initial work. It sets up some | |
1242 | % flags and things, builds the |\halign| preamble, and returns. | |
1243 | % | |
1244 | % \begin{macrocode} | |
1245 | \def\@eqnarray#1{% | |
1246 | % \end{macrocode} | |
1247 | % | |
1248 | % Start playing with the counter here. The original does some icky internal | |
1249 | % playing, which isn't necessary. The |\if@eqnsw| switch is |true| if the | |
1250 | % user hasn't supplied an equation number. The |\if@eqalast| switch is | |
1251 | % |true| in the final equation-number column. | |
1252 | % | |
1253 | % \begin{macrocode} | |
1254 | \refstepcounter{equation}% | |
1255 | \@eqalastfalse% | |
1256 | \global\@eqnswtrue% | |
1257 | \m@th% | |
1258 | % \end{macrocode} | |
1259 | % | |
1260 | % Set things up for the |\halign| which is coming up. | |
1261 | % | |
1262 | % \begin{macrocode} | |
1263 | \openup\jot% | |
1264 | \tabskip\eqaopenskip% | |
1265 | \let\\\@eqncr% | |
1266 | \everycr{}% | |
1267 | $$% | |
1268 | % \end{macrocode} | |
1269 | % | |
1270 | % We'll build the real |\halign| and preamble in a token register. All we | |
1271 | % need to do is stuff the header in the token register, clear a switch | |
1272 | % (that'll be explained later), parse the preamble and then expand the | |
1273 | % tokens we collected. Easy, no? | |
1274 | % | |
1275 | % \begin{macrocode} | |
1276 | \toks@{\halign to\displaywidth\bgroup}% | |
1277 | \@tempswafalse% | |
1278 | \eqa@preamble#1\end% | |
1279 | \the\toks@\cr% | |
1280 | } | |
1281 | % \end{macrocode} | |
1282 | % | |
1283 | % \end{macro} | |
1284 | % | |
1285 | % \subsubsection{Parsing the preamble} | |
1286 | % | |
1287 | % All this actually involves is reading the next character and building a | |
1288 | % command from it. That can pull off an argument if it needs it. Just make | |
1289 | % sure we don't fall off the end and we'll be OK. | |
1290 | % | |
1291 | % \begin{macrocode} | |
1292 | \def\eqa@preamble#1{% | |
1293 | \ifx\end#1\else\csname eqa@char@#1\expandafter\endcsname\fi% | |
1294 | } | |
1295 | % \end{macrocode} | |
1296 | % | |
1297 | % Adding stuff to the preamble tokens is a simple matter of using | |
1298 | % |\expandafter| in the correct way.\footnote{^^A | |
1299 | % I have no idea why \LaTeX\ uses \cmd\edef\ for building its preamble. It | |
1300 | % seems utterly insane to me -- the amount of bodgery that \env{tabular} | |
1301 | % has to go through to make everything expand at the appropriate times is | |
1302 | % scary. Maybe Messrs~Lamport and Mittelbach just forgot about token | |
1303 | % registers when they were writing the code. Maybe I ought to rewrite the | |
1304 | % thing properly some time. Sigh. | |
1305 | % | |
1306 | % As a sort of postscript to the above, I \emph{have} rewritten the | |
1307 | % \env{tabular} environment, and made a damned fine job of it, in my | |
1308 | % oh-so-humble opinion. All this \env{eqnarray} stuff has been remoulded | |
1309 | % in terms of the generic column-defining things in \package{mdwtab}. | |
1310 | % You're reading the documentation of the old version, which isn't | |
1311 | % supported any more, so any bugs here are your own problem.} | |
1312 | % | |
1313 | % \begin{macrocode} | |
1314 | \def\eqa@addraw#1{\expandafter\toks@\expandafter{\the\toks@#1}} | |
1315 | % \end{macrocode} | |
1316 | % | |
1317 | % Now for some cleverness again. In order to put all the right bits of | |
1318 | % |\tabskip| glue in the right places we must \emph{not} terminate each | |
1319 | % column until we know what the next one is. We set |\if@tempswa| to be | |
1320 | % |true| if there's a column waiting to be closed (so it's initially | |
1321 | % |false|). The following macro adds a column correctly, assuming we're in | |
1322 | % a formula. Other column types make their own arrangements. | |
1323 | % | |
1324 | % \begin{macrocode} | |
1325 | \def\eqa@add#1{% | |
1326 | \if@tempswa% | |
1327 | \eqa@addraw{\tabskip\eqainskip}% | |
1328 | \else% | |
1329 | \eqa@addraw{#1}% | |
1330 | \fi% | |
1331 | \@tempswatrue% | |
1332 | } | |
1333 | % \end{macrocode} | |
1334 | % | |
1335 | % Now to defining column types. Let's define a macro which allows us to | |
1336 | % define column types: | |
1337 | % | |
1338 | % \begin{macrocode} | |
1339 | \def\eqa@def#1{\expandafter\def\csname eqa@char@#1\endcsname} | |
1340 | % \end{macrocode} | |
1341 | % | |
1342 | % Now we can define the column types. Each column type must loop back to | |
1343 | % |\eqa@preamble| once it's finished, to read the rest of the preamble | |
1344 | % string. Note the positioning of ord atoms in the stuff below. This will | |
1345 | % space out relations and binops correctly when they occur at the edges of | |
1346 | % columns, and won't affect ord atoms at the edges, because ords pack | |
1347 | % closely. | |
1348 | % | |
1349 | % First the easy onces. Just stick |\hfil| in the right places and | |
1350 | % everything will be all right. | |
1351 | % | |
1352 | % \begin{macrocode} | |
1353 | \eqa@def r{\eqa@add{\hfil$\eqa@style##{}$}\eqa@preamble} | |
1354 | \eqa@def c{\eqa@add{\hfil$\eqa@style{}##{}$\hfil}\eqa@preamble} | |
1355 | \eqa@def l{\eqa@add{$\eqa@style{}##$\hfil}\eqa@preamble} | |
1356 | \eqa@def x{\eqa@add{\hfil$\eqa@style##$\hfil}\eqa@preamble} | |
1357 | % \end{macrocode} | |
1358 | % | |
1359 | % Now for the textual ones. This is also fairly easy. | |
1360 | % | |
1361 | % \begin{macrocode} | |
1362 | \eqa@def T#1{% | |
1363 | \eqa@add{}% | |
1364 | \if#1l\else\eqa@addraw{\hfil}\fi% | |
1365 | \eqa@addraw{##}% | |
1366 | \if#1r\else\eqa@addraw{\hfil}\fi% | |
1367 | \eqa@preamble% | |
1368 | } | |
1369 | % \end{macrocode} | |
1370 | % | |
1371 | % Sort of split types of equations. I mustn't use |\rlap| here, or | |
1372 | % everything goes wrong -- |\\| doesn't get noticed by \TeX\ in the same way | |
1373 | % as |\cr| does. | |
1374 | % | |
1375 | % \begin{macrocode} | |
1376 | \eqa@def L{\eqa@add{\hb@xt@\z@{$\eqa@style##$\hss}\qquad}\eqa@preamble} | |
1377 | % \end{macrocode} | |
1378 | % | |
1379 | % The \lit{:} column type is fairly simple. We set |\tabskip| up to make | |
1380 | % lots of space and close the current column, because there must be one.^^A | |
1381 | % \footnote{This is an assumption.} | |
1382 | % | |
1383 | % \begin{macrocode} | |
1384 | \eqa@def :{% | |
1385 | \eqa@addraw{\tabskip\eqacolskip&}\@tempswafalse\eqa@preamble% | |
1386 | } | |
1387 | \eqa@def q{\eqa@add{\quad}\@tempswafalse\eqa@preamble} | |
1388 | % \end{macrocode} | |
1389 | % | |
1390 | % The other column types just insert given text in an appropriate way. | |
1391 | % | |
1392 | % \begin{macrocode} | |
1393 | \eqa@def >#1{\eqa@add{#1}\@tempswafalse\eqa@preamble} | |
1394 | \eqa@def <#1{\eqa@addraw{#1}\eqa@preamble} | |
1395 | % \end{macrocode} | |
1396 | % | |
1397 | % Finally, the magical \lit{!} column type, which sets the equation number. | |
1398 | % We set up the |\tabskip| glue properly, tab on, and set the flag which | |
1399 | % marks the final column. | |
1400 | % | |
1401 | % \begin{macrocode} | |
1402 | \eqa@def !#1{% | |
1403 | \eqa@addraw{\tabskip\eqacloseskip&\@eqalasttrue#1}\eqa@preamble% | |
1404 | } | |
1405 | % \end{macrocode} | |
1406 | % | |
1407 | % \subsubsection{Newline codes} | |
1408 | % | |
1409 | % Newline sequences (|\\|) get turned into calls of |\@eqncr|. The job is | |
1410 | % fairly simple, really. However, to avoid reading `|&|' characters | |
1411 | % prematurely, we set up a magic brace (from the \package{array} package -- | |
1412 | % this avoids creating ord atoms and other nastyness). | |
1413 | % | |
1414 | % \begin{macrocode} | |
1415 | \def\@eqncr{% | |
1416 | \iffalse{\fi\ifnum0=`}\fi% | |
1417 | \@ifstar{\eqacr@i{\@M}}{\eqacr@i{\interdisplaylinepenalty}}% | |
1418 | } | |
1419 | \def\eqacr@i#1{\@ifnextchar[{\eqacr@ii{#1}}{\eqacr@ii{#1}[\z@]}} | |
1420 | \def\eqacr@ii#1[#2]{% | |
1421 | \ifnum0=`{}\fi% | |
1422 | \eqa@eqnum% | |
1423 | \noalign{\penalty#1\vskip#2\relax}% | |
1424 | } | |
1425 | % \end{macrocode} | |
1426 | % | |
1427 | % \subsubsection{Setting equation numbers} | |
1428 | % | |
1429 | % Before we start, we need to generalise the flush-left number handling bits. | |
1430 | % The macro |\eqa@eqpos| will put its argument in the right place. | |
1431 | % | |
1432 | % \begin{macrocode} | |
1433 | \if@leqno | |
1434 | \def\eqa@eqpos#1{% | |
1435 | \hb@xt@.01\p@{}\rlap{\normalfont\normalcolor\hskip-\displaywidth#1}% | |
1436 | } | |
1437 | \else | |
1438 | \def\eqa@eqpos#1{\normalfont\normalcolor#1} | |
1439 | \fi | |
1440 | % \end{macrocode} | |
1441 | % | |
1442 | % First we need to move into the right column. Then we just set the equation | |
1443 | % number appropriately. There is some subtlety here, ish. The |\relax| is | |
1444 | % important, to delay expansion of the |\if|\dots\ until the new column has | |
1445 | % been started. The two helper macros are important too, to hide `|&|'s and | |
1446 | % `|\cr|'s from \TeX's scanner until the right time. | |
1447 | % | |
1448 | % \begin{macrocode} | |
1449 | \def\eqa@eqnum{% | |
1450 | \relax% | |
1451 | \if@eqalast\expandafter\eqa@eqnum@i\else\expandafter\eqa@eqnum@ii\fi% | |
1452 | } | |
1453 | \def\eqa@eqnum@i{% | |
1454 | \if@eqnsw% | |
1455 | \eqa@eqpos{(\theequation)}\stepcounter{equation}% | |
1456 | \else% | |
1457 | \eqa@eqpos\eqa@number% | |
1458 | \fi% | |
1459 | \global\@eqnswtrue% | |
1460 | \cr% | |
1461 | } | |
1462 | \def\eqa@eqnum@ii{&\eqa@eqnum} | |
1463 | % \end{macrocode} | |
1464 | % | |
1465 | % \subsubsection{Numbering control} | |
1466 | % | |
1467 | % This is trivial. We set the |\if@eqnsw| flag to be |false| and store the | |
1468 | % text in a macro. | |
1469 | % | |
1470 | % \begin{macrocode} | |
1471 | \let\nonumber\relax | |
1472 | \newcommand\nonumber[1][]{\global\@eqnswfalse\global\def\eqa@number{#1}} | |
1473 | % \end{macrocode} | |
1474 | % | |
1475 | % \subsubsection{Closing the environments off} | |
1476 | % | |
1477 | % This is really easy. Set the final equation number, close the |\halign|, | |
1478 | % tidy up the equation counter (it's been stepped once too many times) and | |
1479 | % close the display. | |
1480 | % | |
1481 | % \begin{macrocode} | |
1482 | \def\endeqnarray{% | |
1483 | \eqa@eqnum% | |
1484 | \egroup% | |
1485 | \global\advance\c@equation\m@ne% | |
1486 | $$% | |
1487 | \global\@ignoretrue% | |
1488 | } | |
1489 | \expandafter\let\csname endeqnarray*\endcsname\endeqnarray | |
1490 | % \end{macrocode} | |
1491 | % | |
1492 | % Now start up the other package again. | |
1493 | % | |
1494 | % \begin{macrocode} | |
1495 | %</oldeqnarray> | |
1496 | %<*package> | |
1497 | % \end{macrocode} | |
1498 | % | |
1499 | % \end{old-eqnarray} | |
1500 | % | |
1501 | % That's all there is. Byebye. | |
1502 | % | |
1503 | % \begin{macrocode} | |
1504 | %</package> | |
1505 | % \end{macrocode} | |
1506 | % | |
1507 | % \hfill Mark Wooding, \today | |
1508 | % | |
1509 | % \Finale | |
1510 | \endinput |