warp_and_refine_until_resolved: support tensor product elements

[Copilot]

TODO:

• Revert repoint in req.txt

warp_and_refine_until_resolved previously raised TypeError for any non-simplex element group. This extends support to TensorProductElementGroup (quads/hexes).

Changes

• meshmode/mesh/generation.py

  • Drop hard SimplexElementGroup-only guard; accept TensorProductElementGroup as well
  • Inline the interpolation error estimator matrix construction (previously delegated to simplex_interp_error_coefficient_estimator_matrix), selecting high-order modes via:
    • sum(mode_id) for simplex elements (total polynomial degree)
    • max(mode_id) for tensor product elements (max per-direction degree, matching Q^k space structure)
  • Eliminates a redundant vdm_inv computation that existed in the original code

• test/test_mesh.py

  • Add test_warp_and_refine_until_resolved_tensor_product: creates a 2D quad mesh, applies a sinusoidal warp, and verifies the function converges and refines elements

mesh = generate_regular_rect_mesh(
    a=(0, 0), b=(1, 1), nelements_per_axis=(3, 3),
    group_cls=TensorProductElementGroup, order=4)

result = warp_and_refine_until_resolved(mesh, warp_mesh, 1e-3)
# Previously raised: TypeError: Unsupported element group type: 'TensorProductElementGroup'

Original prompt

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This section details on the original issue you should resolve

<issue_title>warp_and_refine_until_resolved: support tensor product elements</issue_title>
<issue_description>cc @ShawnL00</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes warp_and_refine_until_resolved: support tensor product elements #493

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[Copilot]

Pull request overview

Extends warp_and_refine_until_resolved to work on Modepy-based non-simplex element groups (notably TensorProductElementGroup for quads/hexes) and adds a regression test to cover the new capability.

Changes:

• Generalize warp_and_refine_until_resolved from simplex-only to ModepyElementGroup and switch to a generic Modepy interpolation error estimator matrix.
• Add a new test exercising warp_and_refine_until_resolved on a warped quad mesh.
• Minor typing cleanup in tensor-product quadrature node reshaping.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
meshmode/mesh/generation.py	Removes simplex-only restriction and uses Modepy’s generic interpolation error estimator for refinement decisions.
test/test_mesh.py	Adds a tensor-product (quad) regression test for warp_and_refine_until_resolved.
meshmode/discretization/poly_element.py	Simplifies node reshaping code by removing an unnecessary cast.

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