dolfin team mailing list archive

[Anders Logg <logg@xxxxxxxxx>]

On Sun, Dec 14, 2008 at 10:48:31PM +0100, Johan Hake wrote:
> On Sunday 14 December 2008 22:42:44 DOLFIN wrote:
> > One or more new changesets pushed to the primary dolfin repository.
> > A short summary of the last three changesets is included below.
> >
> > changeset:   5342:80da9660bd6639498aee34b430340877a017b08d
> > tag:         tip
> > parent:      5341:b69b68ceb0b70ec4c387c8bdf7c0a94164e07e98
> > parent:      5340:8e01a163726d6ddc2d72382bf1e5ec1d4b86522c
> > user:        "Johan Hake <hake@xxxxxxxxx>"
> > date:        Sun Dec 14 22:42:41 2008 +0100
> > files:       TODO
> > description:
> > merge
> >
> >
> > changeset:   5341:b69b68ceb0b70ec4c387c8bdf7c0a94164e07e98
> > parent:      5335:11eae42fc1852b3b0aca0d247ed0d2f003b05201
> > user:        "Johan Hake <hake@xxxxxxxxx>"
> > date:        Sun Dec 14 22:41:08 2008 +0100
> > files:       TODO demo/pde/periodic/python/demo.py
> > dolfin/swig/dolfin_mesh_pre.i dolfin/swig/typemaps.i
> > site-packages/dolfin/compile_function.py description:
> > Fixed periodic python demo.
> >   - Added a director typemap for "double *y" in map
> 
> In addition to fix the typemap I also had to change
> 
>   bc0 = DirichletBC(V, u0, DirichletBoundary())
> 
> to
> 
>   dbc = DirichletBoundary()
>   bc0 = DirichletBC(V, u0, dbc)
> 
> This is probably not obvious but a quite common error related to swig 
> generated python classes. 
> 
> The DirichletBoundary subdomain get garbage collected killing its C++ 
> equivalent. We therefore have to keep a reference in the demo, which prevents 
> this.
> 
> Johan

ok, do we expect this to get better once we get shared pointers
working across C++/Python?

Creating an anonymous instance of the SubDomain works fine in the
Poisson demo (and other demos that use DirichletBC), but not when
using PeriodicBC. The reason is that for DirichletBC, the SubDomain is
used by the constructor to build an internal data structure (in the
form of a MeshFunction) which is later used by apply(), but for
PeriodicBC, the SubDomain is stored and later used by apply().

-- 
Anders

Attachment: signature.asc
Description: Digital signature