KSPGetResidualNorm#
Gets the last (possibly approximate and/or preconditioned) residual norm that has been computed.
Synopsis#
#include "petscksp.h"
PetscErrorCode KSPGetResidualNorm(KSP ksp, PetscReal *rnorm)
Not Collective
Input Parameter#
ksp - the iterative context
Output Parameter#
rnorm - residual norm
Notes#
For some methods, such as KSPGMRES, the norm is not computed directly from the residual.
The type of norm used by the method can be controlled with KSPSetNormType()
Certain solvers, under certain conditions, may not compute the final residual norm in an iteration, in that case the previous norm is returned.
See Also#
KSP: Linear System Solvers, KSP, KSPSetNormType(), KSPBuildResidual(), KSPNormType
Level#
intermediate
Location#
Examples#
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages