Figures with Multiple Subplots Axes can be added to a matplotlib Figure canvas manually using fig.add_axes or using a sub-figure layout manager such as subplots, subplot2grid, or gridspec. Subplots ...

You'll also need to use this line to see plots in the notebook: %matplotlib inline That line is only for jupyter notebooks, if you are using another editor, you'll use: plt.show() at the end of all ...

I suspect the problem is that matplotlib needs constant-length arrays to plot two on the same plot. For each 'tick' of the animate function it will need to know what value to write for that instant.