ufl team mailing list archive

["Martin Sandve Alnæs" <martinal@xxxxxxxxx>]

2008/9/29 Anders Logg <logg@xxxxxxxxx>:
> On Mon, Sep 29, 2008 at 11:03:14PM +0200, Martin Sandve Alnæs wrote:
>> I was wondering how you intended to use that :)
>
> I was planning to count the number of products each basis function
> appeared in. That worked but then I realized that's not what we need.
> We need to know how many of each basis function appears in a product.

And that no basis functions appear as arguments to nonlinear functions like exp.

You commented that is_multilinear is FFC-specific. But a valid form must
always be multilinear in the basis functions, but not in functions. Right?

>> Lets discuss how to best do this soon, I can show you
>> how I've been thinking in the other algorithms as well.
>
> It can be easily implemented using the monomials() function I just
> added. It returns a list of tuples, where each tuple is a product of
> basis functions.
>
> The final monomials() function will do some more, like propagating all
> linear (differential) operators to the basis functions.

I was considering that propagation a part of the AD implementation.
If we write algorithms separately we'll probably duplicate several things
in different but non-orthogonal ways.

Is this monomials() approach to is_multilinear possible to generalize
to non-polynomial forms? Otherwise it's very FFC specific.

--
Martin