Hi Matt, this is a follow-up to the previous question: I have created a short code as below to create a sub-dm on the surface, extracted from the original volume dmplex: ------------------------------------- call DMClone(dm_origin, dm_wall, ierr);CHKERRA(ierr) ! label for face sets call DMGetLabel(dm_wall, "Face Sets", label_facesets, ierr);CHKERRA(ierr) call DMPlexLabelComplete(dm_wall, label_facesets, ierr);CHKERRA(ierr) ! label for vertex on surface call DMCreateLabel(dm_wall, "Wall", ierr);CHKERRA(ierr) call DMGetLabel(dm_wall, "Wall", label_surf, ierr);CHKERRA(ierr) call DMPlexGetChart(dm_wall, ist, iend, ierr);CHKERRA(ierr) do i=ist,iend call DMLabelGetValue(label_facesets, i, val, ierr);CHKERRA(ierr) if(val .eq. ID_wall) then call DMLabelSetValue(label_surf, i, ID_wall, ierr);CHKERRA(ierr) endif enddo call DMPlexLabelComplete(dm_wall, label_surf, ierr);CHKERRA(ierr) ! create submesh call DMPlexCreateSubmesh(dm_wall, label_surf, ID_wall, PETSC_TRUE, dm_sub, ierr);CHKERRA(ierr) call DMPlexGetSubpointMap(dm_sub, label_sub, ierr);CHKERRA(ierr) ------------------------------------- It is a bit unclear how to map the vector on each vertex of the original volume dm (dm_wall) into the subdm (dm_sub). The function DMPlexGetSubpointMap() seems to create a subpointMap (label_sub) for this mapping, but it is hard to get an idea how to use that DMLabel for the mapping. Shall I create DMCreateInterpolation()? But it uses Mat and Vec to define mapping rule. Could I ask for any comments? Thanks, Mike
Yes, you can use DMPlexCreateSubmesh() (and friends depending on exactly what kind of submesh you want). This will allow you to create a vector over only this mesh, and map your volumetric solution to that subvector. Then you can view the subvector (which pulls in the submesh).
Thanks,
Matt
On Mon, Aug 1, 2022 at 10:59 PM Jed Brown <[email protected]> wrote:
I would create a sub-DM containing only the part you want to view.
Mike Michell <[email protected]> writes:
Hi,
I am a user of DMPlex object in 3D grid topology. Currently the solution field is printed out using viewer PETSCVIEWERVTK in .vtu format. By doing that the entire volume components are written in the file. I was wondering if there is an option that I can tell PETSc viewer to print out only surface component, instead of the entire volume.
Best, Mike
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