petsc-3.7.7 2017-09-25

PCSetDiagonalScale

Indicates the left scaling to use to apply an additional left and right scaling as needed by certain time-stepping codes.

#include "petscksp.h" 
PetscErrorCode  PCSetDiagonalScale(PC pc,Vec s)

Logically Collective on PC

	pc	- the preconditioner context
	s	- scaling vector

Notes: 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

PCDiagonalScaleLeft() scales a vector by D. PCDiagonalScaleRight() scales a vector by D^{-1}.