PCApplyRichardson#
Applies several steps of Richardson iteration with the particular preconditioner. This routine is usually used by the Krylov solvers and not the application code directly.
Synopsis#
#include "petscksp.h"
PetscErrorCode PCApplyRichardson(PC pc, Vec b, Vec y, Vec w, PetscReal rtol, PetscReal abstol, PetscReal dtol, PetscInt its, PetscBool guesszero, PetscInt *outits, PCRichardsonConvergedReason *reason)
Collective
Input Parameters#
pc - the preconditioner context
b - the right-hand side
w - one work vector
rtol - relative decrease in residual norm convergence criteria
abstol - absolute residual norm convergence criteria
dtol - divergence residual norm increase criteria
its - the number of iterations to apply.
guesszero - if the input x contains nonzero initial guess
Output Parameters#
outits - number of iterations actually used (for SOR this always equals its)
reason - the reason the apply terminated
y - the solution (also contains initial guess if guesszero is
PETSC_FALSE
Notes#
Most preconditioners do not support this function. Use the command
PCApplyRichardsonExists() to determine if one does.
Except for the PCMG this routine ignores the convergence tolerances
and always runs for the number of iterations
See Also#
Level#
developer
Location#
Implementations#
PCApplyRichardson_PFMG() in src/ksp/pc/impls/hypre/hypre.c
PCApplyRichardson_SysPFMG() in src/ksp/pc/impls/hypre/hypre.c
PCApplyRichardson_SMG() in src/ksp/pc/impls/hypre/hypre.c
PCApplyRichardson_MG() in src/ksp/pc/impls/mg/mg.c
PCApplyRichardson_Shell() in src/ksp/pc/impls/shell/shellpc.c
PCApplyRichardson_SOR() in src/ksp/pc/impls/sor/sor.c
PCApplyRichardson_Telescope() in src/ksp/pc/impls/telescope/telescope.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages