slepc-3.16.0 2021-09-30
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Defines the computational interval for spectrum slicing.


#include "slepcpep.h" 
PetscErrorCode PEPSetInterval(PEP pep,PetscReal inta,PetscReal intb)
Logically Collective on pep

Input Parameters

pep  - eigensolver context
inta  - left end of the interval
intb  - right end of the interval

Options Database Key

-pep_interval <a,b>  - set [a,b] as the interval of interest


Spectrum slicing is a technique employed for computing all eigenvalues of symmetric eigenproblems in a given interval. This function provides the interval to be considered. It must be used in combination with PEP_ALL, see PEPSetWhichEigenpairs().

In the command-line option, two values must be provided. For an open interval, one can give an infinite, e.g., -pep_interval 1.0,inf or -pep_interval -inf,1.0. An open interval in the programmatic interface can be specified with PETSC_MAX_REAL and -PETSC_MAX_REAL.

See Also

PEPGetInterval(), PEPSetWhichEigenpairs()

Location: src/pep/interface/pepbasic.c



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