petsc-3.12.5 2020-03-29
PCGetDiagonalScale
Indicates if the preconditioner applies an additional left and right scaling as needed by certain time-stepping codes.
Synopsis
#include "petscksp.h"
PetscErrorCode PCGetDiagonalScale(PC pc,PetscBool *flag)
Logically Collective on PC
Input Parameter
pc -the preconditioner context
Output Parameter
flag -PETSC_TRUE if it applies the scaling
Notes
If this returns PETSC_TRUE then the system solved via the Krylov method is
D M A D^{-1} y = D M b for left preconditioning or
D A M D^{-1} z = D b for right preconditioning
See Also
PCCreate(), PCSetUp(), PCDiagonalScaleLeft(), PCDiagonalScaleRight(), PCSetDiagonalScale()
Level
developer
Location
src/ksp/pc/interface/precon.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages