KSPGMRESSetOrthogonalization#

Sets the orthogonalization routine used by KSPGMRES and KSPFGMRES.

Synopsis#

#include "petscksp.h"  
PetscErrorCode KSPGMRESSetOrthogonalization(KSP ksp, PetscErrorCode (*fcn)(KSP ksp, PetscInt it))

Logically Collective

Input Parameters#

  • ksp - iterative context obtained from KSPCreate()

  • fcn - orthogonalization function

Calling sequence of fcn#

  • ksp - the solver context

  • it - the current iteration

Options Database Keys#

  • -ksp_gmres_classicalgramschmidt - Activates KSPGMRESClassicalGramSchmidtOrthogonalization() (default)

  • -ksp_gmres_modifiedgramschmidt - Activates KSPGMRESModifiedGramSchmidtOrthogonalization()

Notes#

Two orthogonalization routines are predefined, KSPGMRESModifiedGramSchmidtOrthogonalization() and the default KSPGMRESClassicalGramSchmidtOrthogonalization().

Use KSPGMRESSetCGSRefinementType() to determine if iterative refinement is used to increase stability.

See Also#

KSP: Linear System Solvers, KSPGMRESSetRestart(), KSPGMRESSetPreAllocateVectors(), KSPGMRESSetCGSRefinementType(), KSPGMRESModifiedGramSchmidtOrthogonalization(), KSPGMRESClassicalGramSchmidtOrthogonalization(), KSPGMRESGetCGSRefinementType()

Level#

intermediate

Location#

src/ksp/ksp/impls/gmres/gmres2.c

Examples#

src/ksp/ksp/tutorials/ex5f.F90

Implementations#

KSPGMRESSetOrthogonalization_GMRES() in src/ksp/ksp/impls/gmres/gmres.c


Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages