KSPSetComputeSingularValues

Sets a flag so that the extreme singular values will be calculated via a Lanczos or Arnoldi process as the linear system is solved.

Synopsis

#include "petscksp.h" 
int KSPSetComputeSingularValues(KSP ksp,PetscTruth flg)

Collective on KSP

Input Parameters

	ksp	- iterative context obtained from KSPCreate()
	flg	- PETSC_TRUE or PETSC_FALSE

Options Database Key

-ksp_singmonitor -Activates KSPSetComputeSingularValues()

Notes

Currently this option is not valid for all iterative methods.

Many users may just want to use the monitoring routine KSPSingularValueMonitor() (which can be set with option -ksp_singmonitor) to print the singular values at each iteration of the linear solve.

Keywords