dolfin team mailing list archive

[Ola Skavhaug <skavhaug@xxxxxxxxx>]

Anders Logg skrev den 11/12-2007 følgende:
> On Tue, Dec 11, 2007 at 02:58:58PM +0000, Garth N. Wells wrote:
> > 
> > 
> > Ola Skavhaug wrote:
> > > Hi,
> > > 
> > > I'm trying to assemble dolfin/FFC forms into a user given matrix format
> > > CRSNew, which inherits GenericTensor as it should. However, the assemble.py in
> > > src/python in dolfin does not allow this.
> > >
> > 
> > assembly.py has rather limited functionality compared to 
> > dolfin::assemble. Does assembly into CRSNew using c++ work?.
> 
> Yes, assemble() in PyDOLFIN currently assumes that you give it an FFC
> form and a Mesh. It then calls the JIT compiler on the form and then
> calls the wrapped C++ assembler on the generated UFC code.
> 
> Does it work if you use cpp_assemble() instead of assemble()?
> 
> We should try and extend assemble() in Python so it can recognize
> various combinations of input arguments (an FFC form or a UFC etc).
> 
> The assemble() function is just a few lines of code and it's defined
> in assemble.py in src/pydolfin/.

I have made assembler more general now. There are still some difficulties
regarding the type information across the user defined linear algebra backend
(CRS in PyCC) and dolfin, but I don't think this will be too hard to fix.

A central question is what to send to assemble from Python. I vote for sending
a factory, since the rank of the assembled tensor is defined by the form (and
hence should not be given as input by the user).

Ola
 
> -- 
> Anders
> _______________________________________________
> DOLFIN-dev mailing list
> DOLFIN-dev@xxxxxxxxxx
> http://www.fenics.org/mailman/listinfo/dolfin-dev