issue_comments: 459368801

Re complexity: It;s probably worth extracting everything to a animate_line function in animate.py?

I've had a go at that in the most recent commits.

I think this is a cool example, and lots of users will probably like it.

Great - it's definitely something I personally want to do all the time.

A high-level question: why was animatplot chosen over matplotlib's animation module?

Because animatplot already abstracts away the creation of the animation, so plotting an animation becomes almost a simple substitution matplotlib.plot.line() -> animatplot.blocks.Line().

Another advantage is that animatplot's block abstraction should make it easier to compose figures made of multiple animated plots, another thing people often want to do but is is awful with matplotlib.funcanimation directly.

(I haven't really looked at how animated facetgrids might work yet, but I suspect that being able to animate a large list of blocks would be helpful too.)

The logic is explained slightly more in #2355, and also looking at animatplot's docs might help you see why I think it's a good idea.

We don't have to use animatplot, but if we didn't I would be suggesting reimplementing something with a similar class structure in xarray as the best approach anyway. The disadvantages of using animatplot are that it's an extra (optional) dependency, and it's not got good unit test coverage yet so someone should probably contribute tests to animatplot upstream before xarray officially relies on it. animatplot isn't particularly large, so if we wanted to reimplement something similar in xarray then that would be feasible.