dolfin team mailing list archive

[Harish Narayanan <harish.mlists@xxxxxxxxx>]

On 9/1/11 1:43 PM, Harish Narayanan wrote:
> On 2/17/10 3:44 PM, Anders Logg wrote:
>> It is now possible to specify the direction of interior facets such
>> that one may know which side of a facet is ('+') and which side is
>> ('-').
>>
>> To use this, attach a MeshFunction over the facets that specifies for
>> each facet which cell (by the cell index) that is the first ('+') side
>> of the cell:
>>
>>   MeshFunction<uint>* facet_orientation = mesh.data().create_mesh_function("facet orientation");
>>
>> Then just fill in the appropriate values in facet_orientation.
>>
>> This is useful for integration over facets where the two sides are not
>> treated symmetrically, for example using upwinding or in multiphysics
>> problems with an interior boundary cutting through the mesh.
> 
> I am trying to use this (from Python) and it is not clear to me how this
> works.
> 
> I do:
> 
> orientation = mesh.data().mesh_function("facet orientation")
> # Populate the mesh function orientation
> 
> How is this information used in the assembler?

No matter, it works with "facet_orientation" instead.

Harish