DMDAVecGetArray#

Returns a multiple dimension array that shares data with the underlying vector and is indexed using the global dimensions.

Synopsis#

#include "petscdmda.h"   
PetscErrorCode DMDAVecGetArray(DM da, Vec vec, void *array)

Logically Collective

Input Parameters#

da - the distributed array
vec - the vector, either a vector the same size as one obtained with DMCreateGlobalVector() or DMCreateLocalVector()

Output Parameter#

array - the array

Notes#

Call DMDAVecRestoreArray() once you have finished accessing the vector entries.

In C, the indexing is “backwards” from what expects: array[k][j][i] NOT array[i][j][k]!

If vec is a local vector (obtained with DMCreateLocalVector() etc) then the ghost point locations are accessible. If it is a global vector then the ghost points are not accessible. Of course with the local vector you will have had to do the

appropriate DMGlobalToLocalBegin() and DMGlobalToLocalEnd() to have correct values in the ghost locations.

Fortran Notes#

Use DMDAVecGetArrayF90() and pass for the array type PetscScalar,pointer :: array(:,…,:) of the appropriate dimension. For a DMDA created with a dof of 1 use the dimension of the DMDA, for a DMDA created with a dof greater than 1 use one more than the dimension of the DMDA.

The order of the indices is array(xs:xs+xm-1,ys:ys+ym-1,zs:zs+zm-1) (when dof is 1) otherwise array(0:dof-1,xs:xs+xm-1,ys:ys+ym-1,zs:zs+zm-1) where the values are obtained from DMDAGetCorners() for a global array or DMDAGetGhostCorners() for a local array.

Level#

intermediate

Location#

src/dm/impls/da/dagetarray.c

Examples#

src/dm/tutorials/ex10.c
src/dm/tutorials/ex14.c
src/dm/tutorials/ex22.c
src/dm/tutorials/ex25.c
src/dm/tutorials/ex2.c
src/dm/tutorials/ex3.c
src/dm/tutorials/swarm_ex1.c
src/ksp/ksp/tutorials/ex29.c
src/ksp/ksp/tutorials/ex32.c
src/ksp/ksp/tutorials/ex42.c
src/ksp/ksp/tutorials/ex43.c

Index of all DMDA routines
Table of Contents for all manual pages
Index of all manual pages