EPSSetOrthogonalization

Specifies the type of orthogonalization technique to be used inside the eigensolver.

Synopsis

#include "slepceps.h" 
int EPSSetOrthogonalization(EPS eps,EPSOrthogonalizationType type, EPSOrthogonalizationRefinementType refinement, PetscReal eta)
Collective on EPS

Input Parameters

eps - the eigensolver context
type - a known type of orthogonalization
refinement - type of refinement
eta - parameter for dynamic refinement

Options Database Keys

-eps_orthog_type <type> - Where <type> is cgs for Classical Gram-Schmidt orthogonalization (default) or mgs for Modified Gram-Schmidt orthogonalization
-eps_orthog_refinement <type> - Where <type> is one of never, ifneeded (default) or always
-eps_orthog_eta <eta> - For setting the value of eta (or PETSC_DEFAULT)

Notes

The value of eta is used only when refinement type is "ifneeded".

The default orthogonalization technique works well for most problems. MGS is numerically more robust than CGS, but CGS may give better scalability.

See Also

EPSGetOrthogonalization()

Level:intermediate
Location:
src/eps/interface/borthog.c
Index of all EPS routines
Table of Contents for all manual pages
Index of all manual pages