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Is there an easy way to repeat a simple piece of text? For example, I want to write $\downarrow$ & $\downarrow$ & $\downarrow$ & ... (for a table). I tried *{8}{$\downarrow$ &}, but it doesn't work...

jamaicanworm
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1 Answers1

27

You could define a command, say \rpt that repeats some command a number of times. Here I've defined \rpt[<repeat>]{<stuff>} that repeats <stuff> <repeat> number of times. <repeat> is an optional parameter, that defaults to 1 if not used:

enter image description here

\documentclass{article}
\usepackage{forloop}% http://ctan.org/pkg/forloop
\newcounter{loopcntr}
\newcommand{\rpt}[2][1]{%
  \forloop{loopcntr}{0}{\value{loopcntr}<#1}{#2}%
}
\begin{document}
\begin{tabular}{*{8}{c}}
  \rpt[7]{$\downarrow$&} \unskip$\downarrow$ \\
  1 & 2 & 3 & 4 & 5 & 6 & 7 & 8
\end{tabular}
\end{document}

It is a very elementary example, but shows how you can shorten your code to repeat something over and over. Looping is provided by forloop which implements a "nested iteration", and is easy to use for small repetitive stuff.

Community
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Werner
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    Very helpful, thanks! What does \unskip do in the 4th-to-last line of your code? – jamaicanworm Dec 07 '11 at 04:37
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    @jamaicanworm: You'll notice that if you remove it, the spacing of the last column is not correct; left over from the last use iteration of \rpt. That space is removed using \unskip. – Werner Dec 07 '11 at 04:42