Add generic nodal/modal bilinear form routines

[a-alveyblanc]

It would be helpful to have a more general version of nodal_quad_mass_matrix. My specific use case for this routine is generating operators representing bilinear forms that have derivatives on the test functions but not necessarily on the trial functions. More generally, this can be useful to generate operators representing bilinear forms whose test and trial functions are not the same.

Functionality of nodal_quad_mass_matrix and modal_quad_mass_matrix are updated to use the new, general routines.

[a-alveyblanc]

Not sure why ruff was failing here. It wasn't failing locally, and I didn't change any of the files the ruff CI test was complaining about. Fixed them anyway, but happy to revert if it seems like a CI bug.

The changes in contrib/weights-from-festa-sommariva were the ones needed to make ruff happy.

[alexfikl]

Not sure why ruff was failing here. It wasn't failing locally, and I didn't change any of the files the ruff CI test was complaining about. Fixed them anyway, but happy to revert if it seems like a CI bug.

The changes in contrib/weights-from-festa-sommariva were the ones needed to make ruff happy.

That's a new check in ruff 0.8.2: astral-sh/ruff#14611. Thanks for fixing it!

[inducer]

Thanks, this looks great! Just a few style quibbles below.

[a-alveyblanc]

Seems like mypy also now has issue with something I didn't touch. I'll take a closer look later today.

[alexfikl]

Seems like mypy also now has issue with something I didn't touch. I'll take a closer look later today.

Those seem to be due to an issue with some new numpy typing changes: numpy/numpy#27957.

[a-alveyblanc]

The first go was a confusing amalgamation of two versions of applying an operator to evaluate a bilinear form. They should now be cleanly separated with names that do a better job of describing what's happening.

What I mean by "two versions" is:

1. We can first compute a "half" operator, i.e. the test functions evaluated at quadrature nodes times quadrature weights, then apply that to a trial solution evaluated at quadrature nodes (implemented as modal_quadrature_operator and nodal_quadrature_operator), or
2. We can first compute a "full" operator, i.e. compute the inner product of test and trial functions using quadrature, then apply that to the coefficients of the trial solution at discretization nodes (implemented as modal_quadrature_bilinear_form and nodal_quadrature_bilinear_form)

Hopefully this is more clear. Happy to convert to a draft if we think more work needs to be done

[alexfikl]

Just took a quick look and left some comments 😁

[inducer]

Unsubscribing... @-mention or request review once it's ready for a look or needs attention.

[a-alveyblanc]

@inducer This is ready for another look

[inducer]

Some thoughts from a quick scroll below.

[inducer]

Thanks, LGTM!