DMDACreatePatchIS#
Creates an index set corresponding to a logically rectangular patch of the DMDA.
Synopsis#
#include "petscdmda.h"
PetscErrorCode DMDACreatePatchIS(DM da, MatStencil *lower, MatStencil *upper, IS *is, PetscBool offproc)
Collective
Input Parameters#
da - the
DMDAlower - a
MatStencilwith i, j and k entries corresponding to the lower corner of the patchupper - a
MatStencilwith i, j and k entries corresponding to the upper corner of the patchoffproc - indicate whether the returned
ISwill contain off process indices
Output Parameter#
is - the
IScorresponding to the patch
Notes#
This routine always returns an IS on the DMDA communicator.
If offproc is set to PETSC_TRUE,
the routine returns an IS with all the indices requested regardless of whether these indices
are present on the requesting MPI process or not. Thus, it is upon the caller to ensure that
the indices returned in this mode are appropriate.
If offproc is set to PETSC_FALSE,
the IS only returns the subset of indices that are present on the requesting MPI process and there
is no duplication of indices between multiple MPI processes.
See Also#
DMDA - Creating vectors for structured grids, DM, DMDA, DMCreateDomainDecomposition(), DMCreateDomainDecompositionScatters()
Level#
developer
Location#
Examples#
src/dm/tutorials/ex22.c
src/dm/tutorials/ex14.c
Index of all DMDA routines
Table of Contents for all manual pages
Index of all manual pages