ffc team mailing list archive

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

Quoting Shawn Walker <walker@xxxxxxxxxxxxxxx>:

> Actually, I am still a little confused.  Whenever you compute an integral
> by quadrature, you need to evaluate the integrand at the quadrature
> points.  Those are the points I need.

If you have a quadrature element in your form

element = FiniteElement("Quadrature", triangle, 2)

you can call the
tabulate_coordinates() function of the dof_map associated with the quadrature
element. If you don't have a quadrature element there is no direct way of
getting the quadrature points.

> I just need the quad rule that is used in a particular case.  I see the
> weights are defined in the tabulate_tensor routine.  Are the points listed
> in a comment somewhere?

No, currently not. But it might be a natural thing to have. I'll look into it.

Kristian

> - Shawn
>
> On Sun, 21 Jun 2009, Kristian Oelgaard wrote:
>
> > Quoting Shawn Walker <walker@xxxxxxxxxxxxxxx>:
> >
> >> This is probably a dumb question, but is it easy to get the actual
> >> quadrature points used in a compiled "tabulate_tensor" routine?  I need
> >> this to try some manual modification of the local FEM matrix.
> >
> > Not sure I understand exactly what you want, but if you want the
> coordinates of
> > the quadrature points, you can use e.g., FiniteElemet("Quadrature", 1) and
> > tabulate the coordinates of the dof_map.
> >
> > Kristian
> >
> >> - Shawn
> >> _______________________________________________
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> >>
> >
> >
> >
>