petsc-3.11.3 2019-06-26
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PCMGSetRScale

Sets the pointwise scaling for the restriction operator from level l to l-1.

Synopsis

#include "petscksp.h" 
PetscErrorCode  PCMGSetRScale(PC pc,PetscInt l,Vec rscale)
Logically Collective on PC and Vec

Input Parameters

pc - the multigrid context
l - the level (0 is coarsest) to supply [Do not supply 0]
rscale -the scaling

Notes

When evaluating a function on a coarse level one does not want to do F(R * x) one does F(rscale * R * x) where rscale is 1 over the row sums of R. It is preferable to use PCMGSetInjection() to control moving primal vectors.

Keywords

MG, set, multigrid, restriction, level

See Also

PCMGSetInterpolation(), PCMGSetRestriction(), PCMGGetRScale(), PCMGSetInjection()

Level

advanced

Location

src/ksp/pc/impls/mg/mgfunc.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages