L2-GridFunction .Other()

Hi, I think we cannot do it directly quite now, but I see two solutions with reasonable effort:

1. Add the Other() operator also to CoefficientFunctions. It becomes a new node in the evaluation tree . We store the 'other' MappedIntegrationRule within the 'this' MappedIntegrationrule. On evaluating the OtherCoefficientFunction the intrules are swapped. If proxies appear within the other - subtree we need special treatment - I would exclude it for the first implementation.

2. The Apply and the AssembleLinearization is working quite now, right ? The problem comes only from the semi-linearization, where we differentiate some terms with respect to the trial-function, but we freeze the trial-function at some other places (and want to use the GridFunction instead). We could add a Freeze - function, which throws away the derivatives of the sub-tree.

Then Alex code would look like
What do you think ? How do we continue ?
Solution 1 (which will find more users soon) needs changes in the core code, I may find some time during the coming week for that, and you can test.
Solution 2 is additive and can be done by Alex, but I think it is quite special purpose.

Joachim

I have added the Other() operator for ordinary CFs.
Pls try it, it's tested only for a few simple cases by now, and certainly it needs some fixes.

Compile is not supported (Compile(True) throws, and Compile(False) falls back to standard evaluation).