DMPlexBuildFromCellListParallel#

Build distributed DMPLEX topology from a list of vertices for each cell (common mesh generator output)

Synopsis#

#include "petscdmplex.h"   
#include "petscdmplex.h"   
PetscErrorCode DMPlexBuildFromCellListParallel(DM dm, PetscInt numCells, PetscInt numVertices, PetscInt NVertices, PetscInt numCorners, const PetscInt cells[], PetscSF *vertexSF, PetscInt **verticesAdjSaved)

Collective; No Fortran Support

Input Parameters#

dm - The DM
numCells - The number of cells owned by this process
numVertices - The number of vertices to be owned by this process, or PETSC_DECIDE
NVertices - The global number of vertices, or PETSC_DETERMINE
numCorners - The number of vertices for each cell
cells - An array of numCells*numCorners numbers, the global vertex numbers for each cell

Output Parameters#

vertexSF - (Optional) PetscSF describing complete vertex ownership
verticesAdjSaved - (Optional) vertex adjacency array

Notes#

Two triangles sharing a face

        2
      / | \
     /  |  \
    /   |   \
   0  0 | 1  3
    \   |   /
     \  |  /
      \ | /
        1

would have input

  numCells = 2, numVertices = 4
  cells = [0 1 2  1 3 2]

which would result in the DMPLEX

        4
      / | \
     /  |  \
    /   |   \
   2  0 | 1  5
    \   |   /
     \  |  /
      \ | /
        3

Vertices are implicitly numbered consecutively 0,…,NVertices. Each rank owns a chunk of numVertices consecutive vertices. If numVertices is PETSC_DECIDE, PETSc will distribute them as evenly as possible using PetscLayout. If NVertices is PETSC_DETERMINE and numVertices is PETSC_DECIDE, NVertices is computed by PETSc as the maximum vertex index in cells + 1. If only NVertices is PETSC_DETERMINE, it is computed as the sum of numVertices over all ranks.

The cell distribution is arbitrary non-overlapping, independent of the vertex distribution.