petsc-3.13.6 2020-09-29

PCMGSetLevels

Sets the number of levels to use with MG. Must be called before any other MG routine.

#include "petscksp.h" 
PetscErrorCode PCMGSetLevels(PC pc,PetscInt levels,MPI_Comm *comms)

Logically Collective on PC

	pc	- the preconditioner context
	levels	- the number of levels
	comms	- optional communicators for each level; this is to allow solving the coarser problems on smaller sets of processors.

If the number of levels is one then the multigrid uses the -mg_levels prefix for setting the level options rather than the -mg_coarse prefix.

intermediate