EPSSetOrthogonalization

Specifies the type of orthogonalization technique to be used inside the eigensolver (classical or modified Gram-Schmidt with or without refinement).

Synopsis

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

Input Parameters

eps - the eigensolver context
type - the type of orthogonalization technique
refinement - type of refinement
eta - parameter for selective 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

Notes

The default settings work well for most problems.

The parameter eta should be a real value between 0 and 1 (or PETSC_DEFAULT). The value of eta is used only when the refinement type is "ifneeded".

When using several processors, MGS is likely to result in bad scalability.

See Also

EPSOrthogonalize(), EPSGetOrthogonalization()

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