petsc-3.7.5 2017-01-01

KSPGetResidualHistory

Gets the array used to hold the residual history and the number of residuals it contains.

Synopsis

#include "petscksp.h" 
PetscErrorCode  KSPGetResidualHistory(KSP ksp,PetscReal *a[],PetscInt *na)

Not Collective

Input Parameter

ksp -iterative context obtained from KSPCreate()

Output Parameters

	a	- pointer to array to hold history (or NULL)
	na	- number of used entries in a (or NULL)

Notes

Can only be called after a KSPSetResidualHistory() otherwise a and na are set to zero

The Fortran version of this routine has a calling sequence

  call KSPGetResidualHistory(KSP ksp, integer na, integer ierr)

note that you have passed a Fortran array into KSPSetResidualHistory() and you need to access the residual values from this Fortran array you provided. Only the na (number of residual norms currently held) is set.

Keywords