[petsc-users] DMPlex Interpolation

Lawrence Mitchell wence at gmx.li
Mon Aug 29 14:12:55 CDT 2022

> I am not sure Injection is going to "do the right thing" when you move between spaces. At least my memory of the implementation
> was that it just did local interpolation, which is not right when injecting P0 into P1.

Ah, that could be the case. For discontinuous things I think what you
want is the L2 projection of the fine function into the coarse space
(which on nested meshes you can compute locally), this is what I
implemented in Firedrake IIRC.

I agree that point interpolating won't work, and I guess in that case
some kind of scaling of a dual thing is approximating the L2


More information about the petsc-users mailing list