Add destaggering functionality

[jthielen]

Change Summary

This is an updated version of #37 to handle de-staggering in all three dimensions and in a (hopefully, still needs to be tested) dask-friendly way.

Currently a draft PR to get eyes on my implementation right away; will be working on tests, documentation updates, and cleaning up the type hints later today.

Related issue number

Closes #35

Checklist

• [x] Unit tests for the changes exist
• [x] Tests pass on CI
• [x] Documentation reflects the changes where applicable

[lpilz]

I think it would be nice to support destaggering multiple dimensions at once. Couldn't we just recursively call _destagger_variable for a single dim?

[jthielen]

I think it would be nice to support destaggering multiple dimensions at once. Couldn't we just recursively call _destagger_variable for a single dim?

It would require a little bit of refactoring of the automatic staggered dim handling and a bit more internal complexity on the accessor methods, but if this is a use case we wanted to support, I could certainly make those changes! That being said, I don't believe I've seen this situation occur in practice. Do you have a sample dataset with such a variable with multiple staggered dimensions?

[lpilz]

You're right, I was originally thinking about maybe finding some variables staggered in z and one of the x or y dimensions, but it seems that this doesn't occur (at least in output data). So nevermind! :D

[jthielen]

While this doesn't add direct tests with dask (deferring to https://github.com/xarray-contrib/xwrf/issues/60 and a later release...perhaps v0.1?), with some some cursory exploration it looks like everything works out for https://github.com/xarray-contrib/xwrf/issues/52#issuecomment-1248425926.

[jthielen]

Thank you for the feedback @lpilz and @andersy005! I believe all the issues raised have been addressed. With an approving review from someone on @xarray-contrib/xwrf-devs, this should be good to merge.

[lpilz]

Awesome work :rocket: Thanks a lot!