slepc-3.16.1 2021-11-17
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Specifies the type of extraction technique to be employed by the eigensolver.


#include "slepceps.h" 
PetscErrorCode EPSSetExtraction(EPS eps,EPSExtraction extr)
Logically Collective on eps

Input Parameters

eps  - the eigensolver context
extr  - a known type of extraction

Options Database Keys

-eps_ritz  - Rayleigh-Ritz extraction
-eps_harmonic  - harmonic Ritz extraction
-eps_harmonic_relative  - harmonic Ritz extraction relative to the eigenvalue
-eps_harmonic_right  - harmonic Ritz extraction for rightmost eigenvalues
-eps_harmonic_largest  - harmonic Ritz extraction for largest magnitude (without target)
-eps_refined  - refined Ritz extraction
-eps_refined_harmonic  - refined harmonic Ritz extraction


Not all eigensolvers support all types of extraction. See the SLEPc Users Manual for details.

By default, a standard Rayleigh-Ritz extraction is used. Other extractions may be useful when computing interior eigenvalues.

Harmonic-type extractions are used in combination with a 'target'.

See Also

EPSSetTarget(), EPSGetExtraction(), EPSExtraction

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