ffc team mailing list archive

[Kristian Oelgaard <k.b.oelgaard@xxxxxxxxxx>]

Quoting Anders Logg <logg@xxxxxxxxx>:

> On Tue, Aug 18, 2009 at 08:13:22PM +0100, Garth N. Wells wrote:
>
> > >>>>>>> changeset:   1612:de211a9d88bce134c4abc2b128283ad35415a529
> > >>>>>>> tag:         tip
> > >>>>>>> user:        "Kristian Oelgaard <k.b.oelgaard@xxxxxxxxxx>"
> > >>>>>>> date:        Tue Aug 18 17:57:36 2009 +0100
> > >>>>>>> files:       ffc/fem/finiteelement.py
> > >>>>>>> description:
> > >>>>>>> Restrictions appears to be working for the Poisson demo.
>
> Excellent!
>
> > > No, only interval, triangle, tetrahedron, quadrilateral and hexahedron
> > >
> > > is predefined in UFL. I assume simplices and restrictions currently only
> > > supports a restriction to one topological dimension lower i.e.,
> > > tetrahedron -> triangle
> > > triangle -> interval
> > >
> >
> > We need a 'facet', which is a triangle in 3D and interval in 2D, so we
> > write dimension-independent forms (at least for 2D and 3D).
>
> That should be fairly easy to add to UFL (__getitem__ in finiteelement.py).
> You can check if the input argument is facet (which needs to be
> added), then look at self._cell and figure out the appropriate value
> of index.
>
> Let me know if you have any trouble.

OK, this functionality should be in place now. Do note that the built-in facet
has no meaning on its own, and it only works with restrictions. I don't know
how to make this implementation better at the moment (it's still work in
progress) but feel free to have a look.

Kristian

> --
> Anders
>
>