petsc-3.13.6 2020-09-29

DMDAGetNeighbors

Gets an array containing the MPI rank of all the current processes neighbors.

#include "petscdmda.h"   
PetscErrorCode  DMDAGetNeighbors(DM da,const PetscMPIInt *ranks[])

Not Collective

da -the DMDA object

ranks -the neighbors ranks, stored with the x index increasing most rapidly. this process itself is in the list

In 2d the array is of length 9, in 3d of length 27 Not supported in 1d Do not free the array, it is freed when the DMDA is destroyed.

In fortran you must pass in an array of the appropriate length.

intermediate