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mapping between nodal points and indices when using MPI

+1 vote

Dear All

I have been busy with writing MPI code for FEniCS
to speed up the calculation of matrices.
I have today realized, that
the mapping between nodal points and indices
depends on whether the matrix for a given mesh FunctionSpace and form is assembled
in parallel serial.
This creates some problems with the interpreation of results , i.e. plotting.

Is there a way to fix that?

regards

Moritz

asked Feb 21, 2014 by moritzbraun FEniCS User (1,390 points)

1 Answer

+2 votes

There are no guarantee for dof numbering in DOLFIN. You need to use the dofmap to get the mapping between mesh entities and dofs for a given FunctionSpace.

That said vertex_to_dof_map and dof_to_vertex_map might help you if you only have nodal (vertex) dofs.

answered Feb 24, 2014 by johanhake FEniCS Expert (22,480 points)
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