# Changing the Label Font Size for xypic Commutative Diagrams

I'm using xymatrix in the xypic package to draw commutative diagrams and I would like for the math in the arrow labels to use the same font size as the math in the rest of the document. Is there an easy way to accomplish this? I've tried various tex commands for locally changing the font size but these don't seem to help. For example,

\documentclass[11pt,letterpaper, oneside]{book}
\usepackage{amsmath}
\usepackage{xypic}
\begin{document}
\xymatrixcolsep{5pc}\xymatrixrowsep{5pc}\xymatrix{
X \ar[d]_{\pi} \ar[rd]^f \\
X/\sim \ar[r]_{\xoversim{f}} & Y
}
\end{document}


produces symbols on the arrow labels that are considerably smaller than the other math symbols in the document. This is understandable since one uses subscript and superscript notation to indicate the labels but results in labels that are difficult to read.

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 It would be helpful to compose a MWE that illustrates the problem including the \documentclass and the appropriate packages so that those trying to help don't have to recreate it. Also, would be good to see what you tried so far. – Peter Grill Nov 21 '11 at 16:13 The arrow labels are typeset in the same size as subscripts and superscripts. You can try something like \ar[r]^{\textstyle f} – egreg Nov 21 '11 at 16:24 @egreg I can confirm that textstyle sizes the fonts correctly on the labels. Is there any way to set this globablly so it doesn't have to be repeated on each arrow label? – 3Sphere Nov 21 '11 at 16:30

## 1 Answer

$\renewcommand{\labelstyle}{\textstyle} \xymatrix@R=5pc@C=5pc{ X \ar[d]_{\pi} \ar[rd]^f \\ X/\sim \ar[r]_{\xoversim{f}} & Y }$


I suggest to leave the setting of \labelstyle inside the math environment, unless you want that all diagrams inherit this setting. Notice a simpler way to specify row and column separation.

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