EPSKrylovSchurGetInertias#

Gets the values of the shifts and their corresponding inertias in case of doing spectrum slicing for a computational interval.

Synopsis#

#include "slepceps.h" 
PetscErrorCode EPSKrylovSchurGetInertias(EPS eps,PetscInt *n,PetscReal *shifts[],PetscInt *inertias[]) PeNS

Not Collective

Input Parameter#

eps - the linear eigensolver context

Output Parameters#

n - number of shifts, including the endpoints of the interval
shifts - the values of the shifts used internally in the solver
inertias - the values of the inertia at each shift

Notes#

If called after EPSSolve(), all shifts used internally by the solver are returned (including both endpoints and any intermediate ones). If called before EPSSolve() and after EPSSetUp() then only the information of the endpoints of subintervals is available.

This function is only available for spectrum slicing runs, that is, when an interval has been given with EPSSetInterval() and STSINVERT is set. See more details in section Spectrum Slicing.

The returned arrays should be freed by the user. Can pass NULL in any of the two arrays if not required.

Fortran Notes#

The calling sequence from Fortran is

   EPSKrylovSchurGetInertias(eps,n,shifts,inertias,ierr)
   PetscInt  n
   PetscReal shifts(*)
   PetscInt  inertias(*)

The arrays should be at least of length n. The value of n can be determined by an initial call

   EPSKrylovSchurGetInertias(eps,n,PETSC_NULL_REAL_ARRAY,PETSC_NULL_INTEGER_ARRAY,ierr)

Level#

advanced

Location#

src/eps/impls/krylov/krylovschur/krylovschur.c

Examples#

src/eps/tutorials/ex12.c
src/eps/tutorials/ex25.c

Implementations#

EPSKrylovSchurGetInertias_KrylovSchur() in src/eps/impls/krylov/krylovschur/krylovschur.c

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