How do I write text in subscript in the axis labels and the legend?

Question

I have the following axis labels and legend.

plt.ylabel(\"ratio_2\")
plt.xlabel(\"n_1\")
plt.legend((\'alpha_1\',\'alpha_2\' ), loc = \'best\',shadow = True)         


        

Answer 1

The easiest way I know is to enable TeX mode for matplotlib,

from http://www.scipy.org/Cookbook/Matplotlib/UsingTex:

from matplotlib import rc
rc('font',**{'family':'sans-serif','sans-serif':['Helvetica']})
rc('text', usetex=True)

Answer 2

Put dollar signs around the formula: plt.xlabel("$n_1$")