How to make a single legend for many subplots with matplotlib

Question

I am plotting the same type of information, but for different countries, with multiple subplots with matplotlib. That is, I have 9 plots on a 3x3 grid, all with the same for lines (of course, different values per line).

However, I have not figured out how to put a single legend (since all 9 subplots have the same lines) on the figure just once.

How do I do that?

Answer 1

Hello @kartik,

There is  nice function get_legend_handles_labels() you can call on the last axis (if you iterate over them) that would collect everything you need from label= arguments:

handles, labels = ax.get_legend_handles_labels()
fig.legend(handles, labels, loc='upper center')

Thank You!