AMR for 2D Parabolic P4est

[DanielDoehring]

This aims to bundle the implementation of parabolic P4est mortars from @jlchan and @apey236 (see #1662) into a recent version of the main repository.

Related to #1147, #1674

[jlchan]

Thanks for porting this PR over and cleaning it up @DanielDoehring! I've added some comment suggestions but otherwise LGTM.

Since I was involved with the original version of this PR, someone else should take a brief look at this as well, at least at the src files.

[jlchan]

I was involved in writing the original version of this PR, so I probably shouldn't be the only reviewer.

@andrewwinters5000 @efaulhaber would either of you be able to take a brief look at the src changes?

[DanielDoehring]

Thanks a lot @jlchan for the valuable comments! Those will sure come in handy to explain the approach taken and remind ourselves in the future :D

[jlchan]

Can you fix the failing formatting tests?

[efaulhaber]

I'm not familiar with the parabolic stuff, and it's been a while since I've written the P4estMesh code (and even longer since I've worked with the AMR parts of Trixi), so I can't really give a good review here without spending too much time.

But it does look like a lot of that code is very similar to existing code in Trixi, so it might be possible to avoid some duplicate code.

[jlchan]

@ranocha @DanielDoehring the only thing failing is the coverage test. It looks like some of it is related to coarsening. Is there a suggested way to test this?

[DanielDoehring]

@ranocha @DanielDoehring the only thing failing is the coverage test. It looks like some of it is related to coarsening. Is there a suggested way to test this?

Not sure what is going on there. The part marked in red is definitely being called (I even added a println statement to be sure) in the test "P4estMesh2D: elixir_advection_diffusion_nonperiodic_amr.jl":

[jlchan]

@ranocha @DanielDoehring the only thing failing is the coverage test. It looks like some of it is related to coarsening. Is there a suggested way to test this?

Not sure what is going on there. The part marked in red is definitely being called (I even added a println statement to be sure) in the test "P4estMesh2D: elixir_advection_diffusion_nonperiodic_amr.jl":

Ah, maybe it's Codecov being weird then.

@ranocha @sloede both Erik and I reviewed this PR. Tests pass except for Codecov, which might be just Codecov weirdness. Are you ok if we merge this?

[ranocha]

Thanks!