ucw-algo.tex

   1 % The UCW Macro Collection: Typesetting of algorithms
   2 % Written by Martin Mares <mj@ucw.cz> in 2018 and placed into public domain
   3 % -------------------------------------------------------------------------
   4
   5 \ucwdefmodule{algo}
   6
   7 %       \algo{name of the algorithm}\algalias{a longer name}
   8 %       \algin input description
   9 %       \:step
  10 %       \:step
  11 %       \::[identifier]nested step
  12 %       \:::yet more nested step
  13 %       \algout output description
  14 %       \endalgo
  15
  16 % Localized strings
  17 \localedef{en}{alg:alg}{Algorithm}
  18 \localedef{en}{alg:proc}{Procedure}
  19 \localedef{en}{alg:in}{Input}
  20 \localedef{en}{alg:out}{Output}
  21
  22 % Spacing (customizable)
  23 \def\algospacing{
  24         \itemnarrow=\itemindent
  25         \interitemskip=1pt
  26         \preitemizeskip=\bigskipamount
  27         \postitemizeskip=\dimexpr \bigskipamount - \parskip \relax
  28 }
  29
  30 \def\algoinit{
  31         \goodbreak
  32         \begingroup
  33         \algospacing
  34         \inititemize
  35         \let\:=\algoitem
  36         \def\={\leftarrow}
  37         \itemcount=0
  38 }
  39
  40 \def\typedalgo#1#2{\algoinit {\bo #1\/} \alg{#2}}
  41 \def\algo#1{\typedalgo{\localestr{alg:alg}}{#1}}
  42 \def\proc#1{\typedalgo{\localestr{alg:proc}}{#1}}
  43 \def\headlessalgo{\algoinit}
  44
  45 \def\endalgo{\goodbreak\endlist\endgroup}
  46 \let\endproc=\endalgo
  47
  48 \def\algopar{
  49         \par
  50         \parindent=2em
  51         \hangindent=2.5em       % \parindent + width of box for the step number
  52         \hangafter=1
  53         \leavevmode
  54 }
  55
  56 \def\algoitem{%
  57         \ifnum\itemcount=0\par\nobreak\smallskip\fi
  58         \algopar\advance\itemcount by 1
  59         \hbox to 0.5em{\hss \the\itemcount.~~}%
  60         \futurelet\next\algoitemh
  61 }
  62
  63 \def\algoitemh{\ifx\next:\let\next=\algohang\else\let\next=\algoitemgo\fi\next}
  64 \def\algohang:{\advance\hangindent by 2em \hskip 2em\futurelet\next\algoitemh}
  65 \optdef\algoitemgo{\ifx\addid\undefined\else\addid{item}{\the\itemcount}\fi}
  66
  67 \def\algin{\par\nobreak{\it \localestr{alg:in}:\/} }
  68 \def\algout{\par\nobreak\parindent=0pt{\it \localestr{alg:in}:\/} }
  69 \def\alginbreak{\hfil\break\hphantom{\it \localestr{alg:out}:\/} }
  70 \def\algalias#1{ (#1)}
  71
  72 % Algorithm name in text or in a formula
  73 \protected\def\alg#1{\leavevmode\hbox{\csc #1}}