% This is macro package used by OpTeX, see http://petr.olsak.net/optex % math.opm, Petr Olšák , 2022 % This file can serve as an template for other package files % See end of the file for more information \_def\_math_version {0.08, 2023-01-28} \_codedecl \replacemissingchars {Doing math more comfortably <\_math_version>} \_namespace{math} \_doc The `math` package provides options, they can be declared using the \`\mathset``{}` macro. For example `\mathset {vert, dots}`. If you create your own package with options, provide a similar `\set` macro. The \`\.kv` macro is similar to \OpTeX's `\kv`, but with specific `pkg:math` dictionary. \_cod \_def\.mathset #1{% \_edef\.restorekvdict{\_kvdict{\_the\_kvdict}}% \_kvdict{pkg:math}% \_nokvx {\_opwarning{\_the\_kvdict: unknown option "##1", ignored}}% \_kvx {vert} {\.smartvert}% sets | as math active, to do better |x| or ||x|| \_kvx {dots} {\.smartdots}% \dots behaves like \ldots or \cdots \_kvx {bfserif} {\.bfserif}% \bf, \bi select fonts with serifs \_kvx {rmchars} {\.rmchars{##1}}% does \.rmchars{} \_kvx {vargreek} {\.vargreek{##1}}% does \.vargreek{} \_kvx {text} {\.dotext{##1}}% does \.dotext{} \_readkv{#1}% \.restorekvdict } \_def\.kv #1{\_trycs{_kv:pkg:math:#1}{\_kvunknown}}% for accessing values given by \mathset \_nspublic \mathset ; \_doc \`\bigp`, \`\Bigp`, \`\biggp`, \`\Biggp`, \`\autop`, \`\normalp` are inspired from \tricklink[bigp]{0094} \_cod \_def\.bigp #1{\.fparam{#1}\_bigl\_bigr} \_def\.Bigp #1{\.fparam{#1}\_Bigl\_Bigr} \_def\.biggp#1{\.fparam{#1}\_biggl\_biggr} \_def\.Biggp#1{\.fparam{#1}\_Biggl\_Biggr} \_def\.autop#1{\.fparam{#1}\_left\_right} \_def\.normalp#1{\.fparam{#1}\_relax\_relax} \_def\.fparam#1#2#3{% \_isequal .{#1}\_iffalse #1\_fi \_let\.bigleft=#2\_let\.bigright=#3\_nospacefuturelet\.next\.fparamA} \_def\.fparamA{% \_casesof \.next ( {\.fparamB()}% [ {\.fparamB[]}% \{ {\.fparamB\{\}}% \_bgroup {\_def\.lparen{\{}\_def\.rparen{\}}\.fparamC}% \_finc {}% } \_def\.fparamB#1#2{% \_def\.lparen{#1}\_def\.rparen{#2}% \_def\.next#1##1#2{\_trick_ensurebalanced#1#2\.fparamC{##1}}% \.next } \_def\.fparamC#1{% \_ifx\.bigleft\_left \_mathopen{}\_bgroup\_fi \.bigleft\.lparen{#1}\.bigright\.rparen \_ifx\.bigright\_right \_egroup\_fi } \_nspublic \bigp \Bigp \biggp \Biggp \autop \normalp ; \_doc We need macro \`\.ensurebalanced``` for balancing nested parentheses from \tricklink[balancing]{0043}. We use `trick` namespace for these macros. \_cod \_resetnamespace{trick} \_def\.ensurebalanced#1#2#3{\_immediateassigned{% \_def\.balopen{#1}\_def\.balclose{#2}\_let\.balaction=#3% \_def\.readnextbal##1##2#2{\.ensurebalancedA{##1#2##2}}}% \.ensurebalancedA} \_def\.ensurebalancedA#1{\.isbalanced#1% \_iftrue\_afterfi{\.balaction{#1}}\_else\_afterfi{\.readnextbal{#1}}\_fi} \_def\.isbalanced#1\_iftrue{\_immediateassignment\_tmpnum=0 \.isbalancedA#1{\.isbalanced}} \_def\.isbalancedA#1#{\.countbalanced#1\.isbalanced \.isbalancedB} \_def\.isbalancedB#1{% \_ifx\.isbalanced#1\_afterfi{\_cs{ifnum}\_tmpnum=0 }\_else\_ea\.isbalancedA\_fi} \_def\.countbalanced#1{\_ea\_ifx\.balopen #1\_immediateassignment\_incr\_tmpnum\_fi \_ea\_ifx\.balclose#1\_immediateassignment\_decr\_tmpnum\_fi \_ifx\.isbalanced#1\_else\_ea\.countbalanced\_fi} \_resetnamespace{math} \_doc \`\smartdots` re-sets `\dots` to `\.dots`. The `\.dots` lets `\.next` using `\futurelet` and checks the `\.next`: It it is declared by `\_chardef` then `\.mchar` is the real Unicode character with `\chardef`ed code. If `\.next` is a real Unicode character then `\.mchar` includes it. This is done by the expandable \o`\cstochar` macro provided by \OpTeX/. If `\.next` is something else (i.e.\ `\.mchar` is empty) then print \o`\ldots` else print \o`\cdots` for Op, Bin, Rel, Open, Close math classes of the `\.next` math object or prints \o`\ldots` in other cases. \_cod \_def\.smartdots {\_let\dots=\.dots} \_def\.dots{\_relax \_ifmmode \_ea\.specdots \_else \_dots \_fi} \_def\.specdots{\_futurelet\.next\.specdotsA} \_def\.specdotsA{% \.ischardef\.next\_iftrue \_edef\.mchar{\_Uchar\.next}% \_else \_edef\.mchar{\_cstochar\.next}% \_fi \_ifx\.mchar\_empty \_ldots \_else \_Umathcharnumdef\.next=\_Umathcode\_ea`\.mchar \_relax \_ifcase \.readclass\.next \_ldots\_or \_cdots\_or \_cdots\_or \_cdots\_or \_cdots\_or \_cdots \_else \_ldots \_fi \_fi } \_def\.ischardef #1\_iftrue {\_ea\.ischardefA\_meaning#1\_fin} \_def\.ischardefA #1#2#3#4#5#6\_fin {\_def\.tmpa{#1#2#3#4#5}\_ifx\.tmpa\.stringchar} \_edef\.stringchar{\_string\char} \_def\.readclass#1{\_ea\.readclassA\_meaning#1\_fin} \_def\.readclassA#1"#2"#3\_fin{#2} \_nspublic \smartdots ; \_doc \`\smartvert` sets `|` as math-active character and declares it equal to `\.autovert` macro. This macro checks two variants: there is single `|` or there is double `||`. It runs \`\.autovertA` or \`\.autoVertA`. These macros find the closing `|` or `||` and use `|` or `‖` in context of `\left`, `\right`. The \`\singlevert` is declared here if a user want to use a single vertical bar. \_cod \_newpublic\_mathchardef \singlevert=\_mathcode`| \_def\.autovert {\_isnextchar|{\.autoVertA}{\.autovertA}} \_def\.autovertA #1|{\_mathopen{}\_mathclose{\_left|#1\_right|}} \_def\.autoVertA|#1||{\_mathopen{}\_mathclose{\_left‖#1\_right‖}} \_bgroup \_lccode`\~=`\| \_lowercase{\_egroup \_def\.smartvert{\_let~=\.autovert \_mathcode`|="8000 }} \_nspublic \smartvert ; \_doc The control sequences \`\N`, \`\Z`, \`\Q`, \`\R`, \`\C` \`\sgn`, \`\argmin`, \`\argmax`, \`\grad`, \`\rank`, \`\tr`, \`\diag`, \`\Span`, \`\Rng`, \`\Null`, \`\Ker`, \`\Res`, \`\tg`, \`\cotg`, \`\arctg`, \`\arccotg`, \`\frac`, \`\dfrac`, \`\tfrac`, \`\.` are defined directly in the user space by \o`\_newpublic`. The \`\.pdef` is a shortcut for `\protected\def`. \_cod \_def\.pdef{\_protected\_def} \_newpublic\.pdef \N {{\_bbchar N}} \_newpublic\.pdef \Z {{\_bbchar Z}} \_newpublic\.pdef \Q {{\_bbchar Q}} \_newpublic\.pdef \R {{\_bbchar R}} \_newpublic\.pdef \C {{\_bbchar C}} \_newpublic\.pdef \sgn {\_mathop{\_rm sgn}\_nolimits} \_newpublic\.pdef \argmin {\_mathop{\_rm argmin}} \_newpublic\.pdef \argmax {\_mathop{\_rm argmax}} \_newpublic\.pdef \grad {\_mathop{\_rm grad}\_nolimits} \_newpublic\.pdef \rank {\_mathop{\_rm rank}\_nolimits} \_newpublic\.pdef \tr {\_mathop{\_rm tr}\_nolimits} \_newpublic\.pdef \diag {\_mathop{\_rm diag}\_nolimits} \_newpublic\.pdef \Span {\_mathop{\_rm Span}\_nolimits} \_newpublic\.pdef \Rng {\_mathop{\_rm Rng}\_nolimits} \_newpublic\.pdef \Null {\_mathop{\_rm Null}\_nolimits} \_newpublic\.pdef \Ker {\_mathop{\_rm Ker}\_nolimits} \_newpublic\.pdef \Res {\_mathop{\_rm Res}\_nolimits} \_newpublic\.pdef \tg {\_mathop{\_rm tg}\_nolimits} \_newpublic\.pdef \cotg {\_mathop{\_rm cotg}\_nolimits} \_newpublic\.pdef \arctg {\_mathop{\_rm arctg}\_nolimits} \_newpublic\.pdef \arccotg {\_mathop{\_rm arccotg}\_nolimits} \_newpublic\.pdef \frac #1#2{{{#1}\_over#2}} \_newpublic\.pdef \dfrac #1#2{{\_displaystyle{{#1}\_over#2}}} \_newpublic\.pdef \tfrac #1#2{{\_textstyle{{#1}\_over#2}}} \_newpublic\.pdef \.#1{{\_bf#1}} \_doc \`\eqsystem``{}` saves its parameter to `\.tmpb` and does a collection of `\_replstring`s. It replaces all spaces by `&` (but ignores the optional first and last space), it removes spaces before `\cr`, it precedes `\mathord` before all `-` (but not if the minus is alone in the column) and runs `\halign`. The \n`\baselineskip` is enlarged by \O`\openup`\`\eqskip`. Each item adds 0.5\`\eqsep` around it and \`\eqfil` to the left side and `\hfil` to the right side. \_cod \_protected \_optdef\.eqsystem[]#1{\_vcenter{% \_def\.tmpb{\.bb#1\.bb}\_replstring\.tmpb{ }{&}% \_replstring\.tmpb{\.bb&}{}\_replstring\.tmpb{&\.bb}{}\_replstring\.tmpb{&\cr}{\cr}% \_replstring\.tmpb{-}{\_mathord-}\_replstring\.tmpb{&\_mathord-&}{&-&}% \_let ~=\_relax \_the\_opt \_relax \_openup\.eqskip \_halign{&\_the\.eqfil\_kern.5\.eqsep$\_displaystyle{{}##{}}$\_kern.5\.eqsep\_hfil\_cr \.tmpb\_crcr}% }} \_let\.bb=\_empty \_newdimen\.eqskip \_newdimen\.eqsep \_newtoks\.eqfil \.eqfil={\_hfill} \_nspublic \eqsystem \eqskip \eqsep \eqfil ; \_doc The \`\toright` and \`\toleft` macros are based on the \o`\setpos` and \o`\posx` macros. The printing point is shifted by `\posx` to the left (i.e.\ to the left boundary of the sheet) and then it is shifted to the desired space by `\kern\hoffset+\hsize`. This idea is moved from \tricklink[torighteq]{0028}. \_cod \_newcount \.tomarginno \_def\.toright #1{\_incr\.tomarginno {\_setpos[_math_tr:\_the\.tomarginno]% \_rlap{\_kern-\_posx[_math_tr:\_the\.tomarginno]\_kern\_hoffset\_kern\_hsize\_llap{#1}}}} \_def\.toleft #1{\_incr\.tomarginno {\_setpos[_math_tr:\_the\.tomarginno]% \_rlap{\_kern-\_posx[_math_tr:\_the\.tomarginno]\_kern\_hoffset\_rlap{#1}}}} \_nspublic \toright \toleft ; \_doc The \`\subeqmark` works because the internal \O`\_thednum` is re-defined. The \`\.dnumpost` is added here. If you want to use another format for \O`\_thednum` then you have to add the \^`\.dnumpost` to it too. \_cod \_def \_thednum {(\_the\_dnum \.dnumpost)} \_def\.dnumpost{} \_def\.subeqmark #1{\_def\.dnumpost{#1}\_lowercase{\_ifx a#1}\_else \_decr\_dnum\_fi \_eqmark} \_nspublic \subeqmark ; \_doc \`\bfserif` re-defines internal \OpTeX/ \O`\_mabf` and \O`\_mabi` macros. \_cod \_def\bfserif{% \_protected\_def\_mabf {\_inmath{\_bfvariables\_bfgreek\_bfGreek\_bfdigits}}% \_protected\_def\_mabi {\_inmath{\_bivariables\_bigreek\_bfGreek\_bfdigits}}% } \_doc \`\rmchars``{}` is implemented using \O`\foreach`. The list is expanded first because we want to expand control sequences like `\alpha` to a real character $\_rmgreek \alpha$.\nl \`\vargreek``{}` is implemented using \O`\foreach`. The parameter is not expanded because we want to keep control sequences like `\alpha` unchanged. \_cod \_def\.rmchars#1{\_ea\_foreach \_expanded{#1}\_do{\_ifx,##1\_else\.rmchar##1\_fi}} \_def\.rmchar#1{\_Umathcode`#1=0 1 `#1 } \_def\.vargreek#1{\_foreach#1\_do{\_ifx,##1\_else \.vargreekchar##1\_fi}} \_def\.vargreekchar#1{% \_ifcsname var\_csstring#1\_endcsname \_slet{\_csstring#1}{var\_csstring#1}% \_else \_opwarning{\_string\vargreek: the \_bslash var\_csstring#1\_space doesn't exists}% \_fi } \_nspublic \rmchars \vargreek ; \_doc \`\textvariables`, \`\textdigits`, \`\textmoremath` initialize new two families 5, 6 using `\.textmathini` and sets `\mathcode`s of given characters to these families. Moreover, `\textvariables` adds `\fam` register setting to `\rm` and `\it` selectors and re-set Greek variables to use only math font (because we are not sure if Greek letters are in the current text fonts).\nl \`\.dotext``{}` runs `\.text` for each in the list. It is used when the option `text={}` is used. \_cod \_def\.textmathini{% \_fontdef\.mathrm{\_rm}\_fontdef\.mathit{\_it}% \_fontdef\.mathbf{\_bf}\_fontdef\.mathbi{\_bi}% \_addto\_normalmath{% \_setmathfamily 5 \.mathrm \_setmathfamily 6 \.mathit }% \_addto\_boldmath{% \_setmathfamily 5 \.mathbf \_setmathfamily 6 \.mathbi }% \_normalmath \_let\.textmathini=\_relax } \_def\.textvariables {\.textmathini \_mathcodes 6 {7{\_Urange a-z \_Urange A-Z}}% \_addto\_marm {\_fam5 }\_addto\_mait{\_fam6 }% \_protected\_def\_itgreek {\_umathrangegreek01\_greekita}% \_protected\_def\_rmgreek {\_umathrangegreek01\_greekrma}% \_protected\_def\_itGreek {\_umathrangeGREEK01\_greekitA} \_protected\_def\_rmGreek {\_umathrangeGREEK01\_greekrmA} \_itgreek \_rmGreek } \_def\.textdigits {\.textmathini \_mathcodes 5 {7{\_Urange 0-9}}} \_def\.textmoremath {\.textmathini \_mathcodes 5 {5{!?} 2{*+-} 3{=<>} 6{,:;} 0{./|} 4{([\{} 5{\})]}}% \_Umathcode `- = 2 5 "2212 % hyphen behaves like minus in math mode } \_def\.dotext#1{\_foreach #1 \_do ##1 {\_trycs{_math_text##1}{\_opwarning{text option: "##1" unknown}}}} \_nspublic \textvariables \textdigits \textmoremath ; \_doc \`\replacemissingchars``` defines `\UnicodeMathSymbol` and reads `unimath-table.opm`, i.e.\ it does for each math character following if the character is missing in main math font and if it is present in added font and if it is not already replaced character then apply new math code or `\Umathaccent` definition. Its name is added to `\.alist` or `\.clist`. The new codes are declared by `\matchars{\clist}`. The `\.rlist` is the list of characters already replaced. They are not replaced again if a new `\replacemissingchars` is used. \_cod \_def\.rlist{\sqrt\cuberoot\fourthroot} % they cannot be replaced by \mathchars \_def\.replacemissingchars#1{% \_def\.alist{}\_def\.clist{} \_def\UnicodeMathSymbol##1##2##3##4{% \_iffontchar\_textfont1##1 \_else % not in main math font \_iffontchar\_textfont#1 ##1 % is presnet in added font \_isinlist\.rlist{##2}\_iffalse % not already replaced \_ifx##3\_mathaccent \_protected\_def##2{\_Umathaccent fixed 7 #1 ##1 }% \_addto\.alist{##2}% \_else \_addto\.clist{##2}% \_fi\_fi\_fi\_fi } \_input unimath-table.opm \_wlog{^^J\_string\replacemissingchars: From \_string\fam=\_string#1 is printed now:^^J% CHARACTERS: \_unexpanded\_ea{\.clist}^^JACCENTS: \_unexpanded\_ea{\.alist}^^J}% \_def\.tmp{\_mathchars #1}\_ea\.tmp\_ea{\.clist}% \_ea\_addto \_ea\.rlist \_ea{\.clist}\_ea\_addto \_ea\.rlist \_ea{\.alist}% \_def\.alist{}\_def\.clist{}\_let\UnicodeMathSymbol=\_undefined } \_nspublic \replacemissingchars ; \_doc \`\scriptspaces``{}{}{}{}` sets internal \LuaTeX/ registers represented by appropriate primitives, see section 7.5 in the \LuaTeX/ manual. \_cod \_def\.scriptspaces #1#2#3#4{% \_Umathordrelspacing\_scriptstyle=\.orzeromu{#1}\_relax \_Umathrelordspacing\_scriptstyle=\.orzeromu{#1}\_relax \_Umathrelopspacing \_scriptstyle=\.orzeromu{#1}\_relax \_Umathordrelspacing\_crampedscriptstyle=\.orzeromu{#1}\_relax \_Umathrelordspacing\_crampedscriptstyle=\.orzeromu{#1}\_relax \_Umathrelopspacing \_crampedscriptstyle=\.orzeromu{#1}\_relax \_Umathordbinspacing\_scriptstyle=\.orzeromu{#2}\_relax \_Umathbinordspacing\_scriptstyle=\.orzeromu{#2}\_relax \_Umathbinopspacing \_scriptstyle=\.orzeromu{#2}\_relax \_Umathordbinspacing\_crampedscriptstyle=\.orzeromu{#2}\_relax \_Umathbinordspacing\_crampedscriptstyle=\.orzeromu{#2}\_relax \_Umathbinopspacing \_crampedscriptstyle=\.orzeromu{#2}\_relax \_Umathordrelspacing\_scriptscriptstyle=\.orzeromu{#3}\_relax \_Umathrelordspacing\_scriptscriptstyle=\.orzeromu{#3}\_relax \_Umathrelopspacing \_scriptscriptstyle=\.orzeromu{#3}\_relax \_Umathordrelspacing\_crampedscriptscriptstyle=\.orzeromu{#3}\_relax \_Umathrelordspacing\_crampedscriptscriptstyle=\.orzeromu{#3}\_relax \_Umathrelopspacing \_crampedscriptscriptstyle=\.orzeromu{#3}\_relax \_Umathordbinspacing\_scriptscriptstyle=\.orzeromu{#4}\_relax \_Umathbinordspacing\_scriptscriptstyle=\.orzeromu{#4}\_relax \_Umathbinopspacing \_scriptscriptstyle=\.orzeromu{#4}\_relax \_Umathordbinspacing\_crampedscriptscriptstyle=\.orzeromu{#4}\_relax \_Umathbinordspacing\_crampedscriptscriptstyle=\.orzeromu{#4}\_relax \_Umathbinopspacing \_crampedscriptscriptstyle=\.orzeromu{#4}\_relax } \_def\.orzeromu#1{\_ifx^#1^0mu\_else#1\_fi} \_nspublic \scriptspaces ; \_endnamespace \_endcode \sec Summary This package provides various extensions usable for math typesetting. Mostly of them are inspired from \ulink[http://petr.olsak.net/optex/optex-tricks.html]{\OpTeX/ tricks} www page. The following macros are defined in this package: \begitems * \~`\bigp`, \~`\Bigp`, \~`\biggp`, \~`\Biggp`, \~`\autop`, \~`\normalp` gives better controlling of sizes of parentheses. * \~`\smartdots` declares `\dots` macro more intelligent. \~`\smartvert` declares \"`|`" for better spacing. * There are many common math macros for sets or for operators, for example \~`\R` or \~`\sgn`. * \~`\eqsystem` enables to write systems of equations comfortably, * \~`\toright`, \~`\toleft` puts the \o`\eqmark` to desired position, \~`\subeqmark` prints the given suffix as a part of the equation mark. * \~`\scriptspaces` sets more spaces around rel, bin in script and scripscript styles. * \~`\bfserif` sets `\bf` and `\bi` for math typesetting as for bold-serif, bold-italic-serif. * \~`\rmchars` sets selected characters printed as `\rm`, \~`\vargreek` sets Greek leters to their variants. * \~`\textvariables`, \~`\textdigits`, \~`\textmoremath` enables characters from used text font in math mode (variables, digits, more characters). * \~`\replacemissingchars` allows to re-declare all characters missing in math font for printing them from additional math font. \enditems Six options are provided by the `math` package. You can set them by \^`\mathset``{}` after `\load[math]`, for example `\mathset{dots, vert, vargreek={\epsilon,\rho}}`. The options are: \begitems * `dots` sets more inteligent `\dots`, the same as \~`\smartdots`. * `vert` sets more inteligent `|`, the same as \~`\smartvert`. * `bfserif` sets bold-serif, bold-italic-serif, the same as \~`\bfserif`. * `rmchars={}` sets `\rm` for selected characters, the same as \~`\rmchars`, see section~\ref[rmchars]. * `vargreek={}` sets variants for Greek letetters, the same as \~`\vargreek`, see section~\ref[rmchars]. * `text={}` sets \~`\textvariables`, \~`\textdigits`, or \~`\textmoremath`, see section~\ref[textvars]. \enditems This package is not definitive. I plan to add more features in new versions if needed. Moreover, this package gives an example for package writers how to write their own packages, see section~\ref[pkgtemplate]. \sec Controlled sizes of parentheses If you write `$f(x(y+z))$` then the outer parentheses should be bigger. Classical Plain \TeX/ provides macros \O`\bigl`, \O`\bigr`, etc., they can be used in this manner: `$f\bigl(x(y+z)\bigr)$`. But the source file looks bad with such markup. Better is to say that parentheses have to be bigger using a single prefix before functional symbol, i.e. `$\bigp f(x(y+z))$`. This should be print the same as previous example with \O`\bigl`, \O`\bigr`. The prefixes \^`\bigp` (big pair), \^`\Bigp` (Big pair), \^`\biggp` (bigg pair) and \^`\Biggp` (Bigg pair) are provided, they can be used before a functional symbol. The scaled parentheses surrounding the functional parameter can be (...) or [...] or `\{`...`\}` or \{...\}. I.e.\ `\Bigp\Gamma [x]` is the same as `\Gamma \Bigl[x\bigr]`. Moreover, the functional parameter gets its own \TeX/ group, so `\Bigp G(a\over2)` results to `G\Bigl({a\over2}\bigr)`. There are two more prefixes \^`\autop` and \^`\normalp`. First one applies `\left`, `\right` to the parentheses of the parameter, second one keeps the parentheses unscaled. If you want to scale the parentheses without preceding functional symbol then use dot instead this symbol, for example `\Bigp.(a)` is equal to `\Bigl(a\Bigr)`. Examples: \begtt $$ \displaylines{ \Biggp F (1+\biggp g (1+\Bigp f(1+\bigp f(1+f(x))))) \cr f(x(y+z)),\quad \bigp f(x(y+z)),\quad \autop f (a\over b)\cr \Bigp f(a\over b+c),\quad \Bigp f(x^2\over2),\quad \Bigp.(a\over b) } $$ \endtt gives: $$ \displaylines{ \Biggp F (1+\biggp g (1+\Bigp f(1+\bigp f(1+f(x))))) \cr f(x(y+z)),\quad \bigp f(x(y+z)),\quad \autop f (a\over b)\cr \Bigp f(a\over b+c),\quad \Bigp f(x^2\over2),\quad \Bigp.(a\over b) } $$ \sec Intelligent `\dots` like in AMS\TeX AMS\TeX/ provides \o`\dots` macro which works depending on the context. If it is surrounded by symbols like $+$, $-$, $=$ then it works like \o`\cdots`, if it is surrounded by comma or similar symbols then it works like \o`\ldots`. This package keeps \o`\dots` unchanged but it is changed (and behaves as mentioned above) after the \^`\smartdots` declaration. \smartdots You can try this after the \^`\smartdots` declaration: \medskip `$a_1, a_2, \dots, a_n$ ` prints $a_1, a_2, \dots, a_n$, `$a_1 + a_2 + \dots + a_n$ ` prints $a_1 + a_2 + \dots + a_n$, \sec Using vertical bars with better spacing The character \"`|`" is declared with Ord class by default in Plain \TeX/, but we are using it typically in the context `$|x|$`. It means there should be Open and Close classes. This example gives correct result but try to use `$|-1|$` which gives bad spacing: $|-1|$. And `$||x||$` gives bad result too. When you declare \^`\smartvert`, these problems are solved. Moreover, the \"`|`" or \"`||`" are expected to be always in pairs and they are scaled by `\left` and `\right` primitives automatically. If you don't want to use it in a pair, use \^`\singlevert` or `\big|`, or `\Big|` etc. Compare the result of `$|\sum a_n|+||x||$`: $$ \eqalign{ |\sum a_n|+||x|| &\quad \hbox{if \scantextokens{`\smartvert`} isn't initialized,}\cr \smartvert |\sum a_n|+||x|| &\quad \hbox{if \scantextokens{`\smartvert`} is initialized.} } $$ \sec Basic and typical macros for sets, functions etc. These typical macros are defined in `math.opm`: \^`\N` for $\N$, \^`\Z` for $\Z$, \^`\Q` for $\Q$, \^`\R` for $\R$, \^`\C` for $\C$, \^`\sgn`, \^`\argmin`, \^`\argmax`, \^`\grad`, \^`\rank`, \^`\tr`, \^`\diag`, \^`\Span`, \^`\Rng`, \^`\Null`, \^`\Ker`, \^`\Res`, \^`\tg`, \^`\cotg`, \^`\arctg`, \^`\arccotg`. I hate the \^`\frac`, \^`\dfrac` and \^`\tfrac` macros defined in \LaTeX/ but someone may want to use them. This package defines them. But I note: usage of `$1\over2$` for $1\over2$ is much more understandable than \LaTeX's `$\frac12$`. The vectors and matrices are usually printed by `{\bf A}{\bf x}`. The package provides a shortcut `\.` to do the same, so user can write `\.A\.x` for multiplication of a matrix $\.A$ by a vector $\.x$. We strictly don't recommend usage of `\.`, `\v`, `\=`, etc.\ for accents, so `math.opm` can define `\.` differently than the classical meaning \"dotaccent". \sec System of equations printed by `\eqsystem` The \^`\eqsystem``{}` enables to write systems of equations more comfortably. The equations are separated by `\cr` and the aligned columns are separated by space. For example: \begtt $$ \eqsystem{ x + y - 2z = 10 \cr 2x - 7y + z = 13 \cr -x + y ~ ~ = -5 } $$ \endtt prints $$ \eqsystem{ x + y - 2z = 10 \cr 2x - 7y + z = 13 \cr -x + y ~ ~ = -5 } $$ Note that empty columns have to be filled by `~` mark. There are columns for variables (possibly multiplied by a constant) and for binary operators `+` and `-` or relations `=`, `>` etc. or constants. Each column is aligned to right. The number of columns is unlimited (we have 7 columns in the example above). All given equations are packed to the `\vcenter` box. The spaces between lines are enlarged by the value of \^`\eqskip` and the horizontal spaces between columns are enlaged by \^`\eqsep`. Both registers are set to 0\,pt by default. The \^`\eqfil` register is \"left filler" applied to each item in the \^`\eqsystem` columns. Its default is `\eqfil={\hfill}`. The right filler is hardwired and it is `\hfil`. This makes columns aligned to right by default. For example, when you set `\eqfil={\hfil}` then you have columns centered. The \^`\eqsystem` macro allows optional parameter which is processed inside group before printing equations. You can do local settings here, for example `\eqsystem[\eqskip=2pt \eqsep=5pt]{...}`. \sec Equation marks in atypical cases We may want to put equation marks `\eqmark` in more lines in display mode when we are using macros not designed for such case. For example in the lines of the `\cases` macro: \begtt $$ f(x) = \cases{0 & for $x<0$\toright\eqmark \cr 1 & otherwise\toright\eqmark } $$ \endtt This puts the equation marks to the right margin in each line generated by the `\cases` macro. $$ f(x) = \cases{0 & for $x\string<0$\toright\eqmark \cr 1 & otherwise\toright\eqmark } $$ The \^`\toright`\o`\eqmark` is used here. Analogically, \^`\toleft`\o`\eqmark` puts the equation mark to the left margin. The position of these marks are correct after second or more \TeX/ run because \TeX/ needs to read data from its previous run in this case. Sometimes we want to declare a bunch of equations with the same numeric equation marks but with different suffixes, for example (1.1a), (1.1b). We provide the macro \^`\subeqmark``` here. If `` is `a` or `A` then \^`\subeqmark` starts a new bunch of equations with the next number. Following `\subeqmark b`, `\subeqmark c`, etc.\ use the same equation number, they differ only by given suffixes: You can put `[