Fix: add missing enable_tensor_type for CartesianLeviCivitaTensor and fix Levi-Civita size() #578

[Quntized]

src/coord_transformations/static_tensors.hpp:

1. Bug fix: Add missing enable_tensor_type specialization for
   CartesianLeviCivitaTensor.

2. Bug fix: Fix size() in both CartesianLeviCivitaTensor and
   LeviCivitaTensor. The previous implementation returned rank() * rank()
   for just rank = 2;

3. Improvement: Use ddc::type_seq_element_t<dim, index_set> for
   IdentityTensor::vector_index_set_t,

4. Improvement: Use ElementType instead of hardcoded double as the
   return type of ddcHelper::get overloads for special tensors.

5. Doc fix: Correct ddcHelper::get doc comments
   "modifiable reference" when the functions return by value.

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[EmilyBourne]

This looks great, but I think at least one extra test would be nice. To tests a different ElementType and maybe to show why CartesianLeviCivitaTensor needs to be enabled as a tensor type

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[EmilyBourne]

@Quntized Commits are squashed when we merge so it is not important to preserve a clean commit history. By force pushing your changes down to 1 commit all you are doing is:

• Making it harder for me to see when review comments have been addressed
• Forcing me to rerun the tests (wasting energy running the same tests multiple times)
• Delaying the merge of the branch

[Quntized]

@EmilyBourne Thanks for the clarification! I didn't realize commits are squashed on merge — I'll just push new commits going forward instead of force-pushing. Sorry for the extra CI runs.

[EmilyBourne]

@tpadioleau @AbdelhadiKara could someone check that this doesn't cause any problems on GPU before I merge please? My WiFi isn't stable enough to use the vpn

[AbdelhadiKara]

@tpadioleau @AbdelhadiKara could someone check that this doesn't cause any problems on GPU before I merge please? My WiFi isn't stable enough to use the vpn

yes,

[AbdelhadiKara]

@EmilyBourne, The tests pass on the V100 architecture, only the simulations related to XVx geometry fail, it is not related to this MR I think. (python tkinter issues)

[Quntized]

@tpadioleau fixed the changes that you suggested and also added in CHANGELOG.md. Let me know if everything looks alright.

[EmilyBourne]

Thomas is on holiday. But I agree that his comments have been addressed. I confirm that the code runs and compiles without warnings on GPU