PCSORGetSymmetric#
Gets the form the SOR preconditioner is using; backward, or forward relaxation. The local variants perform SOR on each processor. By default forward relaxation is used.
Synopsis#
#include "petscpc.h"
PetscErrorCode PCSORGetSymmetric(PC pc, MatSORType *flag)
Logically Collective
Input Parameter#
pc - the preconditioner context
Output Parameter#
flag - one of the following
Options Database Keys#
-pc_sor_symmetric - Activates symmetric version
-pc_sor_backward - Activates backward version
-pc_sor_local_forward - Activates local forward version
-pc_sor_local_symmetric - Activates local symmetric version
-pc_sor_local_backward - Activates local backward version
Note#
To use the Eisenstat trick with SSOR, employ the PCEISENSTAT
preconditioner,
which can be chosen with the option
-pc_type eisenstat - Activates Eisenstat trick
See Also#
KSP: Linear System Solvers, PCSOR
, PCEisenstatSetOmega()
, PCSORSetIterations()
, PCSORSetOmega()
, PCSORSetSymmetric()
Level#
intermediate
Location#
Implementations#
PCSORGetSymmetric_SOR() in src/ksp/pc/impls/sor/sor.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages