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Question on interface integrals at material boundaries in DG formulation

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4 years 8 months ago #1746 by joachim
Replied by joachim on topic Question on interface integrals at material boundaries in DG formulation
The first version produces 0 element-matrices, and tries to assemble them. But the global matrix has no entries allocated, and thus throws an exception.

The translate to dx/ds syntax should be
Code:
a +=uhat.Trace()*vhat.Trace()*ds(definedon=mesh.Boundaries("b2"))
We want a loop over boundary elements, no need for volume elements and thus no skeleton flag.
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4 years 8 months ago #1747 by Guosheng Fu
Replied by Guosheng Fu on topic Question on interface integrals at material boundaries in DG formulation
Thanks again for the clarification.
Previously, I used ds(skeleton=True,...), it gives me an error.
Now, I tried the same thing in 1D, and it seems .Trace() is not properly implemented yet for 1D Facet Dofs. It gives me this error message:

netgen.libngpy._meshing.NgException: FacetFESpace::GetSFE: unsupported element Point
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4 years 8 months ago #1748 by Guosheng Fu
Replied by Guosheng Fu on topic Question on interface integrals at material boundaries in DG formulation
Here is the code produce the error message
Attachments:
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