Use std::vector instead of Table

[pcafrica]

Follow-up from #12993.

This fix bypasses the memory leak, which by the way still requires further investigation.

closes #12993

[kronbichler]

I think this is a good local solution. Next we need to find out the problem for the AlignedVector.

[peterrum]

/rebuild

[peterrum]

@elauksap What is the reason that this PR is still "draft"?

[pcafrica]

@elauksap What is the reason that this PR is still "draft"?

Just removed that label 😉 I was waiting for the tests on my local machine to complete.

[bangerth]

I like the solution with the statically typed array. Would this be something we could also apply to other similar classes? If so, want to write a patch?

[pcafrica]

@bangerth thanks, I'd be glad to help! It's not easy to spot similar cases in the library, but will try my best.

For example, ShapeInfo seems one of those classes to investigate.

[bangerth]

I was specifically thinking of the other polynomial classes.

[pcafrica]

I was specifically thinking of the other polynomial classes.

Ok, I see! You mean to replace, e.g., Tensor<1, dim> by std::array<GradType, dim> and so on like here and in all similar places, right?

[bangerth]

I think that doesn't work because you don't know how many basis functions you have, and so it really needs to be a dynamic std::vector or Table rather than a fixed size std::array. The beauty of your patch is that it avoids the dynamic allocation of memory by a statically sized object.

I don't know whether there are other similar opportunities in the classes I mentioned. It's possible that there are none, I was just wondering whether there are :-)

[pcafrica]

As far as I can see, after some searching and grepping, there is no other polynomial class where this patch can be applied.

[bangerth]

OK, thanks for checking!