petsc-3.9.4 2018-09-11

PCApplyBAorAB

Applies the preconditioner and operator to a vector. y = B*A*x or y = A*B*x.

Synopsis

#include "petscksp.h" 
PetscErrorCode  PCApplyBAorAB(PC pc,PCSide side,Vec x,Vec y,Vec work)

Collective on PC and Vec

Input Parameters

	pc	- the preconditioner context
	side	- indicates the preconditioner side, one of PC_LEFT, PC_RIGHT, or PC_SYMMETRIC
	x	- input vector
	work	- work vector

Output Parameter

y -output vector

Notes: If the PC has had PCSetDiagonalScale() set then D M A D^{-1} for left preconditioning or D A M D^{-1} is actually applied. Note that the specific KSPSolve() method must also be written to handle the post-solve "correction" for the diagonal scaling.

Keywords

PC, apply, operator

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