KSPBuildResidualDefault#

Default code to compute the residual.

Synopsis#

#include "petscksp.h" 
PetscErrorCode KSPBuildResidualDefault(KSP ksp, Vec t, Vec v, Vec *V)

Collecive on ksp

Input Parameters#

ksp - iterative context
t - pointer to temporary vector
v - pointer to user vector

Output Parameter#

V - pointer to a vector containing the residual

Note#

Some KSP methods such as KSPGMRES do not compute the explicit residual at each iteration, this routine takes the information they have computed during the previous iterations and uses it to compute the explicit residual via the formula r = b - A*x.

Developer Note#

This is PETSC_EXTERN because it may be used by user written plugin KSPType implementations

Level#

advanced

Location#

src/ksp/ksp/interface/iterativ.c

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