Martin F Krafft <[EMAIL PROTECTED]> writes:
MFK> how can you {add,multiply,negate,divide} two scalars in TeX/LaTeX?
MFK>
MFK> in a new command that i am writing (it places a \picture), i want to
MFK> use one of the two arguments (width) and \linewidth or \textwidth to
MFK> calculate the remaining horizontal space i have (for another picture).
MFK>
MFK> i know i can convert a #1 argument of a command into a \length with
MFK> \newlength\setlength, but how can i mathematically combine multiple
MFK> \lengths? i know it's possible, though maybe not on the LaTeX level.
(Looks through TeXbook) It looks like you can only do this if one of
the things is a named length. But in that case you can do things
like:
% Make \mylen be the width of the page less 5ex.
\setlength\mylen\textwidth
\addtolength\mylen{-5ex}
% Or, equivalently,
\advance\mylen by -5ex
% Make \mylen be 15ex.
\setlength\mylen{5ex}
\multiply\mylen by 3
% Doesn't look like there's a LaTeX equivalent for this one.
You also want to be slightly careful when dealing with lengths. For
example:
\newcommand{\spacetext}[2]{\hskip#1#2}
will do the wrong thing if you try to do, say, \spacetext{10ex}{plus
3ex foo bar bax quux}, since TeX will read "10ex plus 3ex" as
stretchable length; you should put a \relax in between #1 and #2 in
this case for safety.
--
David Maze [EMAIL PROTECTED] http://people.debian.org/~dmaze/
"Theoretical politics is interesting. Politicking should be illegal."
-- Abra Mitchell
