I came across this page: http://www.scipy.org/Cookbook/Matplotlib/UsingTex
which mentions using LaTeX to generate labels on plots in Matplotlib.
What I only discovered recently is that you don't need this 'usetext=1'
thing in order to create captions on plots that include subscripts, etc.
According to section 2.6.4 of the user's guide, you can just surround
your text with $...$ to have it formatted as if it were latex. This is
especially important if you're exporting SVG graphics (eg if you want to
add more captioning/labelling using inkscape): the 'usetex' approach
fails in that case.
I wonder if someone with write access to the scipy wiki could maybe
update the above page with some comments about the 'mathtext' support in
Matplotlib? It might also be worth noting that the mathtext
functionality doesn't support the \frac operator.
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