On Mon, Nov 03, 2008 at 11:22:26AM +0000, Garth N. Wells wrote: > > > Anders Logg wrote: > > On Sun, Nov 02, 2008 at 06:29:25PM +0000, Garth N. Wells wrote: > >> > >> Anders Logg wrote: > >>> On Sun, Nov 02, 2008 at 05:52:21PM +0000, Garth N. Wells wrote: > >>>> Do we want to insist that Dirichlet bc functions that do not appear > >>>> inside a form are constructed with a FunctionSpace? DirichletBC is > >>>> supplied with a FunctionSpace, so if the bc Function does not have a > >>>> FunctionSpace, we could attach one automatically. > >>>> > >>>> Garth > >>>> _______________________________________________ > >>>> DOLFIN-dev mailing list > >>>> [email protected] > >>>> http://www.fenics.org/mailman/listinfo/dolfin-dev > >>> I think this is already handled. Look in the Poisson demo. It uses a > >>> Constant to set the BC and it does not have a FunctionSpace attached > >>> to it. The DirichletBC class now uses its own FunctionSpace rather > >>> than the one that the Function has (if any). There is a check (in > >>> DirichletBC::check()) that checks that the FunctionSpace for the > >>> Function is the same as the one in the DirichletBC. > >>> > >> It works for Constant, but not for Functions. I was getting an error > >> when Function::interpolate is called. Function::interpolate leads to > >> eval being called, in which case there is a test for the FunctionSpace > >> which fails. Constant provides its own eval and therefore doesn't have a > >> problem. > >> > >> For now, I've added a test in DirichletBC for the FunctionSpace. What we > >> can add is an attach function if there is no FunctionSpace associated. > >> > >> Garth > > > > In which demo does this show up? Is there a simple way I can comment > > something out to reproduce the error so I understand what goes wrong? > > > > Look at /demo/nls/nonlinearpoisson/cpp. > > If you change > > DirichletBoundaryCondition g(V, t); > > to > > DirichletBoundaryCondition g(t); > > it will break down. > > Garth
ok I see the problem now. The problem is a user may choose to either overload a scalar eval function or a tensor eval function and we need to decide which one after the callback from ufc::function::evaluate(). If the FunctionSpace is not known, we can't decide which one to pick. If we insist that one should be able to pass a Function without a FunctionSpace to a DirichletBC, then we must remove the scalar eval function. -- Anders
signature.asc
Description: Digital signature
_______________________________________________ DOLFIN-dev mailing list [email protected] http://www.fenics.org/mailman/listinfo/dolfin-dev
