Note that Paraview already knows the cell number and can display it Now that would have been useful to know months ago.
Here is me making a similar field containing the rank instead of the cell number: Yes I ended up cannibalizing that function and this worked well enough. One thing I noticed however is that it the global vector this creates is of the size of number of cells, but when I create a global vector it is the size of num vertices. I omitted the PETSc__rank_ options prefix part when creating the default fe, is that responsible for setting the vec size here? Best, Jacob On Oct 4, 2019, at 9:42 AM, Matthew Knepley <knep...@gmail.com<mailto:knep...@gmail.com>> wrote: On Thu, Oct 3, 2019 at 11:42 AM Matthew Knepley <knep...@gmail.com<mailto:knep...@gmail.com>> wrote: On Tue, Oct 1, 2019 at 11:57 AM Faibussowitsch, Jacob via petsc-dev <petsc-dev@mcs.anl.gov<mailto:petsc-dev@mcs.anl.gov>> wrote: Hello All, I am plotting an output value from a vecview, and want to show in a separate plot which cells correspond to which values in the vec. I plan to do this by making a field on the cells whose value is the global number of that cell. I have 2 issues with this: 1. How do I guarantee that the ordering of the Vec I made corresponds to the DMPlex cell ordering such that Vec(0) corresponds to Cells(0) etc. (I make the Vec separately from the DM since using DMCreateLocalVector makes a vector on the vertices) 2. I am trying to use DMPlexVTKWriteAll to make my output, so I am adding my field to the DMPlexVTK using PetscViewerVTKAddField, but I can’t seem to get PetscViewerVTKWriteFunction to work properly, and the man pages don’t link to an example. Here is my code for this section: PetscErrorCode (*PetscViewerVTKWriteFunction) (PetscObject, PetscViewer); ierr = PetscViewerCreate(comm=PETSC_COMM_WORLD, &vtkviewer);CHKERRQ(ierr); ierr = PetscViewerVTKOpen(comm=PETSC_COMM_WORLD, "mesh.vtk", FILE_MODE_WRITE, &vtkviewer);CHKERRQ(ierr); ierr = PetscViewerSetUp(vtkviewer);CHKERRQ(ierr); PetscViewerVTKWriteFunction = (CellNum vtkviewer); ierr = PetscViewerVTKAddField(vtkviewer, (PetscObject) dm, PetscViewerVTKWriteFunction, PETSC_VTK_CELL_FIELD, PETSC_TRUE, CellNum);CHKERRQ(ierr); ierr = DMPlexVTKWriteAll((PetscObject) dm, vtkviewer);CHKERRQ(ierr); Any help would be greatly appreciated! I think what you want is to make a Section over cells with 1 dof, fill it with the cell number (from a global numbering), and then view that Vec. Here is me making a similar field containing the rank instead of the cell number: https://www.mcs.anl.gov/petsc/petsc-master/docs/manualpages/DMPLEX/DMPlexCreateRankField.html Note that Paraview already knows the cell number and can display it Thanks, Matt Matt Best, Jacob -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://www.cse.buffalo.edu/~knepley/<http://www.cse.buffalo.edu/~knepley/> -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://www.cse.buffalo.edu/~knepley/<http://www.cse.buffalo.edu/~knepley/>
