petsc-3.12.5 2020-03-29

DMCreateInterpolation

Gets interpolation matrix between two DM objects

Synopsis

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

Collective on dm1

Input Parameter

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

Output Parameter

	mat	- the interpolation
	vec	- the scaling (optional)

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.

For DMDA objects you can use this interpolation (more precisely the interpolation from the DMGetCoordinateDM()) to interpolate the mesh coordinate vectors EXCEPT in the periodic case where it does not make sense since the coordinate vectors are not periodic.

Level

developer

Location

src/dm/interface/dm.c

Examples

src/dm/examples/tutorials/ex3.c.html
src/ksp/ksp/examples/tutorials/ex42.c.html
src/ksp/ksp/examples/tutorials/ex65.c.html
src/ksp/ksp/examples/tutorials/ex73.c.html
src/snes/examples/tutorials/ex48.c.html

Implementations