[texhax] Counters as ordinal numbers

[Philip G. Ratcliffe]

> I need to have a counter that counts like "first, second, third, fourrth,
> ...".  (say up to ten thousandth). I can create a counter and put all of
> these in it just like:
> 
> \def\@mycounter#1{%
>   \ifcase#1\or First\or Second\or Third\or ...\else\@ctrerr\fi}
> 
> \def\mycounter#1{\expandafter\@mycounter\csname c@#1\endcsname}
> 
> But it will be  very annoying to put each single of these in \@mycounter. 
> I was wondering if you know a better solution.

The following is something I put together years ago (and it's admittedly not very kosher) for cardinals - it shouldn't be hard to modify for you needs.
It is to be used on counters just as \alph or \arabic etc.  So \words{page} will give output "one" on page one.

There may well be already something more kosher on CTAN - have a look.

Cheers,    Phil Ratcliffe

Put what follows in a file, say  "words.sty" and then load it as a package.

\def\words#1{\@words{\@nameuse{c@#1}}}
\def\@words#1{\@tempcnta=#1\relax \@tempswafalse
  \ifnum\@tempcnta=0 zero \else
    \ifnum\@tempcnta<0 \multiply\@tempcnta by-1 \@tempswatrue \fi
    \@tempcntb=\@tempcnta \divide\@tempcntb by1000
    \ifnum\@tempcntb>19 \@ctrerr \else
    \if at tempswa minus \@tempswafalse \fi
      \ifnum\@tempcntb>0 \@tempswatrue \unitswords{\@tempcntb} thousand%
        \multiply\@tempcntb by1000 \advance\@tempcnta by-\@tempcntb \fi
      \@tempcntb=\@tempcnta \divide\@tempcntb by100
      \ifnum\@tempcntb>0 \if at tempswa \space \fi
                         \@tempswatrue \unitswords{\@tempcntb} hundred%
        \multiply\@tempcntb by100  \advance\@tempcnta by-\@tempcntb \fi
      \if at tempswa \ifnum\@tempcnta>0 \space and \fi \fi
      \@tempcntb=\@tempcnta \divide\@tempcntb by10
      \ifnum\@tempcntb>1 \tenswords{\@tempcntb}%
        \multiply\@tempcntb by10   \advance\@tempcnta by-\@tempcntb \fi
      \ifnum\@tempcnta>0 \unitswords{\@tempcnta}\fi
    \fi
  \fi}

\def\unitswords#1{\ifcase#1\or one\or two\or three\or four\or five\or six\or
 seven\or eight\or nine\or ten\or eleven\or twelve\or thirteen\or fourteen\or
 fifteen\or sixteen\or seventeen\or eighteen\or nineteen\else \@ctrerr \fi}

\def\tenswords#1{\ifcase#1\or ten\or twenty\or thirty\or forty\or fifty\or
sixty\or seventy\or eighty\or ninety\else \@ctrerr \fi}