petsc-3.12.5 2020-03-29

KSPConvergedDefaultSetUIRNorm

makes the default convergence test use || B*(b - A*(initial guess))|| instead of || B*b ||. In the case of right preconditioner or if KSPSetNormType(ksp,KSP_NORM_UNPRECONDIITONED) is used there is no B in the above formula. UIRNorm is short for Use Initial Residual Norm.

Synopsis

#include "petscksp.h" 
PetscErrorCode  KSPConvergedDefaultSetUIRNorm(KSP ksp)

Collective on ksp

Input Parameters

ksp -iterative context

Options Database

-ksp_converged_use_initial_residual_norm - Notes: Use KSPSetTolerances() to alter the defaults for rtol, abstol, dtol.

The precise values of reason are macros such as KSP_CONVERGED_RTOL, which are defined in petscksp.h.

If the convergence test is not KSPConvergedDefault() then this is ignored.

If right preconditioning is being used then B does not appear in the above formula.

Level

intermediate

Location