KSPOrthogonalizationModifiedGramSchmidt#
This is the basic orthogonalization routine using modified Gram-Schmidt.
Synopsis#
#include "petscksp.h"
PetscErrorCode KSPOrthogonalizationModifiedGramSchmidt(KSP ksp, Vec V[], PetscInt n, Vec x, PetscScalar h[])
Collective
Input Parameters#
ksp - the Krylov space solver context
V - array of previously computed orthonormal vectors
n - number of vectors
x - vector to be orthogonalized, modified on output (may be
NULL)
Output Parameter#
h - computed orthogonalization coefficients
Options Database Key#
-ksp_orthogonalization mgs - choose modified Gram-Schmidt (MGS) for orthogonalization
Notes#
If no x is given, then the vector to be orthogonalized is assumed to be located at V[n].
The input vectors V must be orthogonal and with unit two-norm. The output vector x is
not normalized.
In general this is much slower than KSPOrthogonalizationClassicalGramSchmidt() but has better stability properties.
See Also#
KSP: Linear System Solvers, KSPOrthogonalizationSet(), KSPOrthogonalizationClassicalGramSchmidt(), KSPOrthogonalizationGet()
Level#
intermediate
Location#
Examples#
src/ksp/ksp/tutorials/ex5f.F90
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages