11

I'm trying to do the following with xymatrix:

image

This is a diagram I drew sometime ago... But now I don't have the source and I can't remember how I did it, nor can I find an easy, simple way to do it.

More specifically, what I forgot how to do is the vertical arrow in the middle.

Werner
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Bruno Stonek
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  • Are you interested in other ways of drawing such diagrams, for example in TikZ? If yes, we could show how this example would look with TikZ, or PSTricks. – Stefan Kottwitz Jan 21 '12 at 09:54
  • @Stefan: Personally, I use xymatrix and I'm happy with it, but perhaps it is valuable to the community that the question be answered most completely; I'll leave it to your judgement. Thank you for the interest. – Bruno Stonek Jan 21 '12 at 12:42
  • I just wanted to show you possibilities, and well readable syntax and fine output of TikZ. No need to extend if you don't really wish it. – Stefan Kottwitz Jan 21 '12 at 12:48

1 Answers1

9

The 2cell module is what you need:

\documentclass{article}
\usepackage[all,cmtip,2cell]{xy}
\UseTwocells

\begin{document}
\[
\xymatrix@C+2pc{
\mathsf{CRing} \rtwocell^{\mathsf{GL}_n}_{U}{\;\;\;\det} & \mathsf{Grp}
}
\]
\end{document}
egreg
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