petsc-3.3-p7 2013-05-11
KSPComputeExtremeSingularValues
Computes the extreme singular values for the preconditioned operator. Called after or during KSPSolve().
Synopsis
#include "petscksp.h"
PetscErrorCode KSPComputeExtremeSingularValues(KSP ksp,PetscReal *emax,PetscReal *emin)
Not Collective
Input Parameter
ksp -iterative context obtained from KSPCreate()
Output Parameters
emin, emax -extreme singular values
Notes
One must call KSPSetComputeSingularValues() before calling KSPSetUp()
(or use the option -ksp_compute_eigenvalues) in order for this routine to work correctly.
Many users may just want to use the monitoring routine
KSPMonitorSingularValue() (which can be set with option -ksp_monitor_singular_value)
to print the extreme singular values at each iteration of the linear solve.
Keywords
KSP, compute, extreme, singular, values
See Also
KSPSetComputeSingularValues(), KSPMonitorSingularValue(), KSPComputeEigenvalues()
Level:advanced
Location:src/ksp/ksp/interface/itfunc.c
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages
Examples
src/ksp/ksp/examples/tutorials/ex56.c.html