#include "petscksp.h" #include "petscmat.h" PetscErrorCode KSPSetPCSide(KSP ksp,PCSide side)Logically Collective on ksp
| ksp | - iterative context obtained from KSPCreate() |
| side | - the preconditioning side, where side is one of |
PC_LEFT - left preconditioning (default)
PC_RIGHT - right preconditioning
PC_SYMMETRIC - symmetric preconditioning
| -ksp_pc_side <right,left,symmetric> |
For methods changing the side of the preconditioner changes the norm type that is used, see KSPSetNormType().
Symmetric preconditioning is currently available only for the KSPQCG method. Note, however, that symmetric preconditioning can be emulated by using either right or left preconditioning and a pre or post processing step.
Setting the PC side often affects the default norm type. See KSPSetNormType() for details.