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How do I find out which way vector basis functions are pointing?

+1 vote

Hi all,

I'm working on FEM-BEM coupling using FEniCS and BEM++ (http://bempp.org). For Maxwell transition problems, I need to match up the trace of a FEniCS N1curl space on the boundary with a BEM++ space.

I have managed to identify which DOFs to use on each boundary edge, but I can't work out how to tell which way the basis functions associated with each DOF is pointing. Is there an easy way to get this data from dolfin?

asked Mar 2, 2016 by mscroggs FEniCS Novice (130 points)

Hi, how about brute force method: evaluate basis at facet midpoint and check the inner product of the result with vector facet_midpoint - cell_midpoint?

commented Mar 4, 2016 by MiroK FEniCS Expert (80,920 points)
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