dolfin team mailing list archive

[kent-and@xxxxxxxxx]

> On Thu, Nov 20, 2008 at 05:24:33PM +0000, Garth N. Wells wrote:
>> 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:   5192:cae1753335d21eddc205e16ed3ac3cef16462454
>> > tag:         tip
>> > user:        Anders Logg <logg@xxxxxxxxx>
>> > date:        Thu Nov 20 18:22:47 2008 +0100
>> > files:       site-packages/dolfin/pde.py
>> > description:
>> > Add note about not using assemble_system until we have worked out a
>> bug
>> > with integration over exterior facets.
>> >
>>
>> Is this also a C++ issue?
>>
>> Garth
>
> I haven't tried but I suspect it is.
>
> The error can be tested easily with the following script which is a
> version of a script Harish just sent me:
>
>
> from dolfin import *
>
> mesh = UnitSquare(2, 2)
> element = FiniteElement("Lagrange", "triangle", 1)
>
> v = TestFunction(element)
> u = TrialFunction(element)
> n = FacetNormal("triangle", mesh)
>
> a = v*u*dx
> L = v*dot(n, n)*ds
>
> # Does not work (b will be 0)
> (A, b) = assemble_system(a, L, [], mesh)
> b.disp()
>
> # Works (b will be nonzero)
> b = assemble(L, mesh)
> b.disp()
>
>

b is not zero for me (dolfin-0.8.1).

Kent