petsc-3.8.4 2018-03-24
Report Typos and Errors


This is the basic orthogonalization routine using classical Gram-Schmidt with possible iterative refinement to improve the stability


PetscErrorCode  KSPGMRESClassicalGramSchmidtOrthogonalization(KSP ksp,PetscInt it)
Collective on KSP

Input Parameters

ksp - KSP object, must be associated with GMRES, FGMRES, or LGMRES Krylov method
its - one less then the current GMRES restart iteration, i.e. the size of the Krylov space

Options Database Keys

-ksp_gmres_classicalgramschmidt - Activates KSPGMRESClassicalGramSchmidtOrthogonalization()
-ksp_gmres_cgs_refinement_type <refine_never,refine_ifneeded,refine_always> - determine if iterative refinement is used to increase the stability of the classical Gram-Schmidt orthogonalization.

Notes: Use KSPGMRESSetCGSRefinementType() to determine if iterative refinement is to be used

See Also

aso: KSPGMRESSetOrthogonalization(), KSPGMRESClassicalGramSchmidtOrthogonalization(), KSPGMRESSetCGSRefinementType(),
KSPGMRESGetCGSRefinementType(), KSPGMRESGetOrthogonalization()

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