dolfin team mailing list archive

[Anders Logg <logg@xxxxxxxxx>]

On Wed, Feb 13, 2008 at 10:50:23PM +0100, cosby@xxxxxxxxx wrote:
> >> On Wed, Feb 13, 2008 at 08:49:09PM +0100, Shilpa Khatri wrote:
> >>> We (Dag and I) are doing this because we would like to have Dolfin
> >>> solve
> >>> the
> >>> Stokes/Navier-Stokes equations as one part of a timestep in our code
> >>> where we
> >>> are moving interfaces that are defined as a random set of points in the
> >>> domain.
> >>>
> >>> Thanks,
> >>> Shilpa
> >>
> >> Then I suggest first finding out which cells those points lie in, then
> >> then for each cell with a point get the expansion coefficients within
> >> that cell, then multiply those coefficients with the values of the
> >> basis functions at the points.
> >>
> >> The basis functions are available from the ufc::finite_element.
> >>
> >> We can implement a suitable interface for this at some point but
> >> until then, you can do it manually.
> >
> > Sounds good. Is the GTS_Interface still in place for searching?
> >
> > /Dag
> 
> I'm a little lost here. How is the ufc module used to get hold
> of the basis functions ?
> 
> Kristen

You need to get hold of a ufc::finite_element and then call
evaluate_basis_function (see UFC manual). If you have a ufc::form,
then you can create a ufc::finite_element by calling
create_finite_element. If you have a dolfin::Form, then first get the
ufc::form by calling form().

-- 
Anders