In #50 (comment) we changed scatter_plot_2d such that it uses ax.plot instead of ax.scatter:

One additional change that is mixed in here is to revert ax.scatter to ax.plot in scatter_plot_2d, since I have observed scatter to make axis limits misbehave in non-trivial ways when applied to practical examples where data have very different scales. This has been documented and will be fixed in matplotlib v3.2, but until that is merged, we should revert to ax.plot. Whilst ax.scatter is more consistent with the name of the function, moving away from that actually neatens up a lot of the colouring issues that we have seen before (#32 #21 #45 #19 #31)

The bugs are supposedly fixed by now. Do we want to go back to ax.scatter? If so, 2.0.0 would be the time to do this.

Apparently ax.plot might be faster, but ax.scatter can potentially do more.

For reference:

• see Notes in https://matplotlib.org/stable/api/_as_gen/matplotlib.pyplot.scatter.html#matplotlib-pyplot-scatter
• https://stackoverflow.com/a/57577220/6135182