What changes in dolfinx 0.8.0?

[srosenbu]

Dolfinx 0.8.0 will introduce some new features that may break some of our code, but also will make some parts of our current code obsolete. I would like to collect these issues here in the thread before we start the next hackathon;)

1. Changes in the initialization of Functionspaces: There are no VectorFunctionSpace,TensorFunctionSpace anymore, and you will be supposed to initialize spaces with a function df.fem.functionspace
2. Quadrature spaces:
   1. Probably don't need extra measure anymore since Spaces know what quadrature rule they have --> QuadratureRule can be removed.
   2. Creation of elements via basix
   3. Interpolation into quadrature spaces is possible --> easier to use than expr.eval(...) and the QuadratureEvaluator class can be removed

@pdiercks , @aradermacher , @div-tyg , @danielandresarcones do you remember any other problems that we had in the last hackathon?

[pdiercks]

Probably don't need extra measure anymore since Spaces know what quadrature rule they have

I was not aware of that. Does the space infer this information from the basix element? Could you maybe provide the source, I would be interested in that :)

Apart, from the things you mentioned I currently do not see any problems.

[srosenbu]

I was not aware of that. Does the space infer this information from the basix element? Could you maybe provide the source, I would be interested in that :)

Ok, I thought I had read that someehwre, but I can't find it anymore and I am now thinking that I just hoped for this feature :D
But I think it should theoretically be possible to implement since the Quadrature spaces know which quadrature rule they have. So, I would need to try some stuff with 0.8 and then we could maybe suggest this feature to the dolfinx team