KSPMonitorSet

Sets an ADDITIONAL function to be called at every iteration to monitor, i.e. display in some way, perhaps by printing in the terminal, the residual norm computed in a KSPSolve()

Synopsis

#include "petscksp.h" 
#include "petscmat.h" 
PetscErrorCode KSPMonitorSet(KSP ksp, KSPMonitorFn *monitor, void *ctx, PetscCtxDestroyFn *monitordestroy)

Logically Collective

Input Parameters

• ksp - iterative solver obtained from KSPCreate()

• monitor - pointer to function (if this is NULL, it turns off monitoring, see KSPMonitorFn

• ctx - [optional] context for private data for the monitor routine (use NULL if no context is needed)

• monitordestroy - [optional] routine that frees monitor context (may be NULL), see PetscCtxDestroyFn for the calling sequence

Options Database Keys

• -ksp_monitor - sets KSPMonitorResidual()

• -ksp_monitor draw - sets KSPMonitorResidualDraw() and plots residual

• -ksp_monitor draw::draw_lg - sets KSPMonitorResidualDrawLG() and plots residual

• -ksp_monitor_pause_final - Pauses any graphics when the solve finishes (only works for internal monitors)

• -ksp_monitor_true_residual - sets KSPMonitorTrueResidual()

• -ksp_monitor_true_residual draw::draw_lg - sets KSPMonitorTrueResidualDrawLG() and plots residual

• -ksp_monitor_max - sets KSPMonitorTrueResidualMax()

• -ksp_monitor_singular_value - sets KSPMonitorSingularValue()

• -ksp_monitor_cancel - cancels all monitors that have been hardwired into a code by calls to KSPMonitorSet(), but does not cancel those set via the options database.

Notes

The options database option -ksp_monitor and related options are the easiest way to turn on KSP iteration monitoring

KSPMonitorRegister() provides a way to associate an options database key with KSP monitor function.

The default is to do no monitoring. To print the residual, or preconditioned residual if KSPSetNormType(ksp,KSP_NORM_PRECONDITIONED) was called, use KSPMonitorResidual() as the monitoring routine, with a PETSCVIEWERASCII as the context.

Several different monitoring routines may be set by calling KSPMonitorSet() multiple times; they will be called in the order in which they were set.

Fortran Note

Only a single monitor function can be set for each KSP object

See Also

KSP: Linear System Solvers, KSPMonitorResidual(), KSPMonitorRegister(), KSPMonitorCancel(), KSP, PetscCtxDestroyFn

Level

beginner

Location

src/ksp/ksp/interface/itfunc.c

Examples

src/ts/tutorials/ex47.c
src/snes/tutorials/ex30.c
src/ksp/ksp/tutorials/ex42.c
src/ksp/ksp/tutorials/ex2f.F90
src/ksp/ksp/tutorials/ex9.c

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