remove italics in latex subscript in matplotlib

Question

I would like to remove the italics font that appears when I use subscripts in labels. For example, the "Teff" in the x-label has "eff" in italics. I would like latex not render it in such a way. Generally, in latex this can be achieved with the \rm{} command. However, that does not work in matplotlib. Please help.

import numpy as np
import matplotlib.pyplot as plt

x = np.arange(10)
y = x

plt.plot(x,y,'ro')
plt.xlabel('Primary T$_{eff}$')

Solution

I have encountered this problem many times and it can be solved with this trick

plt.xlabel(r'Primary T$_{\rm eff}$')

Comments

[fjarri]

\rm works for me. Just to be sure, are you escaping the backslash?

[tacaswell]

Are you using p3k? Escaping is going to get nasty. You might need to do '\\rm{eff}'.

[Werner]

I would suggest using $T_{\mathrm{eff}}$, unless T is used in text mode within your document.

[Rohit]

\mathrm did the job for me. No, I am using Python 2.7. Thanks a lot all of you!

[sodd]

In LaTeX2e the \rm command is deprecated, and should not be used.

[nijoakim]

'Primary T$_\mathrm{eff}$' also works if you are worried about deprecation.