Sorry, I have been traveling. I just got back to this. The problem is that _everything_ that goes in the submesh has to have the same label value. That way you can distinguish exactly what you want in. However, the boundary label has to make decisions about shared edges and vertices. I am attaching a modified code that does what you want by making a separate label for each side. I apologize for the C. I am just not as quick in Fortran. Thanks, Matt On Thu, Nov 6, 2025 at 1:42 AM Aldo Bonfiglioli <[email protected]> wrote:
Dear all,
I am having troubles in using DMPlexExtractSubMesh to extract the different strata of the Face Sets of a given mesh.
When run on the enclosed tetrahedral mesh of the unit cube generated with gmsh
Face Sets: 6 strata with value/size (1 (246), 2 (246), 3 (246), 4 (246), 5 (242), 6 (242))
I would expect 246 "points" on stratum 3, but when I DMview the subdm (and plot it) the surface mesh looks incomplete
DM Object: patch_03 1 MPI process type: plex patch_03 in 2 dimensions: Cells are at height 1 Number of 0-cells per rank: 122 Number of 1-cells per rank: 325 Number of 2-cells per rank: 204 Number of 3-cells per rank: 204 [204] Labels: celltype: 4 strata with value/size (0 (122), 1 (325), 3 (204), 12 (204)) depth: 4 strata with value/size (0 (122), 1 (325), 2 (204), 3 (204)) Cell Sets: 1 strata with value/size (1 (204)) Face Sets: 1 strata with value/size (3 (204)) Edge Sets: 2 strata with value/size (1 (8), 5 (8))
see also patch_03.pdf
What am I doing wrong?
A simple reproducer (compiles with petsc-3.24.0) and the gmsh mesh are enclosed.
Thanks,
Aldo
-- Dr. Aldo Bonfiglioli Associate professor of Fluid Mechanics Dipartimento di Ingegneria Universita' della Basilicata V.le dell'Ateneo Lucano, 10 85100 Potenza ITALY tel:+39.0971.205203 fax:+39.0971.205215 web: https://urldefense.us/v3/__http://docenti.unibas.it/site/home/docente.html?m... <https://urldefense.us/v3/__http://docenti.unibas.it/site/home/docente.html?m=002423__;!!G_uCfscf7eWS!aMKmGG4aim9XcbNSnDyHUkDyhUkQHGZ-u-xX2C-sycYUMmtTij6AwqsQbZPXJSvPp9KUfgwRJK2Ok6Me2BLgO0en1w4QF2fHo7s$>
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