How do I write a Latex formula in the legend of a plot using Matplotlib inside a .py file?

Question

I am writing a script in Python (.py file) and I am using Matplotlib to plot an array. I want to add a legend with a formula to the plot, but I haven't been able to do it. I have done this before in IPython or the terminal. In this case, writing something like this:

legend(ur'$The_formula$') 

worked perfectly. However, this doesn't work when I call my .py script from the terminal/IPython.

Answer 1

The easiest way is to assign the label when you plot the data, e.g.:

import matplotlib.pyplot as plt ax = plt.gca()  # or any other way to get an axis object ax.plot(x, y, label=r'$\sin (x)$')  ax.legend()