KSP_GMRES_CGS_REFINE_IFNEEDED#

Do the classical (unmodified) Gram-Schmidt process and one step of iterative refinement if an estimate of the orthogonality of the resulting vectors indicates poor orthogonality.

Note#

This is slower than KSP_GMRES_CGS_REFINE_NEVER because it requires an extra norm computation to estimate the orthogonality but is more stable.

See Also#

KSP: Linear System Solvers, KSPGMRESCGSRefinementType, KSPGMRESClassicalGramSchmidtOrthogonalization(), KSPGMRESSetOrthogonalization(), KSP, KSPGMRESGetOrthogonalization(), KSPGMRESSetCGSRefinementType(), KSPGMRESGetCGSRefinementType(), KSP_GMRES_CGS_REFINE_NEVER, KSP_GMRES_CGS_REFINE_ALWAYS, KSPGMRESModifiedGramSchmidtOrthogonalization()

Level#

advanced

Location#

include/petscksp.h


Edit on GitLab

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