Okay, what Plex is saying is that Gmsh gave it a facet (a set of vertices), but those are not the vertices of any tetrahedral face in the mesh. It is hard to verify such a thing with 12K tets. I have definitely read in GMsh files before with facets, so I don't think the code is completely wrong. Would it be possible to make a smaller mesh (10-20 cells) that shows the same bug? Thanks, Matt On Tue, May 18, 2021 at 12:25 PM Karin&NiKo <[email protected]> wrote:
Sure! I send you both, one with the facets and one without.
Thanks, Nicolas
Le mar. 18 mai 2021 à 17:49, Matthew Knepley <[email protected]> a écrit :
On Tue, May 18, 2021 at 8:18 AM Karin&NiKo <[email protected]> wrote:
Dear PETSc team,
I have tried to load a test mesh available in Gmsh' s demos directory (share/doc/gmsh/demos/simple_geo/filter.geo, attached to this email) as a DMPlex. So I produced a msh4 file by doing : gmsh -3 filter.geo -o /tmp/test.msh4 Then I used src/dm/impls/plex/tutorials/ex2.c to load the mesh by doing : ./ex2 -filename /tmp/test.msh4
Unfortunately I get the error :
[0]PETSC ERROR: --------------------- Error Message -------------------------------------------------------------- [0]PETSC ERROR: No support for this operation for this object type [0]PETSC ERROR: Could not determine Plex facet for Gmsh element 1268 (Plex cell 12681)
The error seems to come from the fact that the msh file contains tets *and* facets *only on the Physical entities* (aka parts of the mesh boundary where the user will assign Dirichlet or Neuman conditions). If I suppress these facets by commenting the "Physical Surface" lines in the geo file and regenerating the mesh, everything is fine.
But the use of these "Physical" stuff is very common in lots of finite element codes in order to assign boundary conditions. How should I do to keep these boundary groups of 2D elements (with corresponding names) ?
Can you also send the *.msh file? I do not have Gmsh on this machine.
Thanks,
Matt
Thanks for your help, Nicolas
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