petsc-3.9.4 2018-09-11

DMCreateRestriction

Gets restriction matrix between two DM objects

Synopsis

#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode  DMCreateRestriction(DM dm1,DM dm2,Mat *mat)

Collective on DM

Input Parameter

	dm1	- the DM object
	dm2	- the second, finer DM object

Output Parameter

mat -the restriction

Notes: For DMDA objects this only works for "uniform refinement", that is the refined mesh was obtained DMRefine() or the coarse mesh was obtained by DMCoarsen(). The coordinates set into the DMDA are completely ignored in computing the interpolation.

Level

developer

Location