Matplotlib Legends not working

Question

Ever since upgrading matplotlib I get the following error whenever trying to create a legend:

/usr/lib/pymodules/python2.7/matplotlib/legend.py:610: UserWarn         


        

Answer 1

Use the "label" keyword, like so:

pyplot.plot(x, y, label='x vs. y')

and then add the legend like so:

pyplot.legend()

The legend will retain line properties like thickness, colours, etc.