MGSetRestriction

Sets the function to be used to restrict vector from level l to l-1.

#include "petscsles.h" 
#include "petscmg.h"   
int MGSetRestriction(PC pc,int l,Mat mat)

Collective on PC and Mat

Usually this is the same matrix used also to set the interpolation for the same level.

One can pass in the interpolation matrix or its transpose; PETSc figures out from the matrix size which one it is.

MG, set, multigrid, restriction, level