petsc-3.4.5 2014-06-29

KSPGetOperators

Gets the matrix associated with the linear system and a (possibly) different one associated with the preconditioner.

Synopsis

#include "petscksp.h" 
PetscErrorCode  KSPGetOperators(KSP ksp,Mat *Amat,Mat *Pmat,MatStructure *flag)
Collective on KSP and Mat

Input Parameter

ksp -the KSP context

Output Parameters

Amat - the matrix that defines the linear system
Pmat - the matrix to be used in constructing the preconditioner, usually the same as Amat.
flag - flag indicating information about the preconditioner matrix structure during successive linear solves. This flag is ignored the first time a linear system is solved, and thus is irrelevant when solving just one linear system.

Notes: DOES NOT increase the reference counts of the matrix, so you should NOT destroy them.

Keywords

KSP, set, get, operators, matrix, preconditioner, linear system

See Also

KSPSolve(), KSPGetPC(), PCGetOperators(), PCSetOperators(), KSPSetOperators(), KSPGetOperatorsSet()

Level:intermediate
Location:
src/ksp/ksp/interface/itcreate.c
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages

Examples

src/ksp/ksp/examples/tutorials/ex25.c.html
src/ksp/ksp/examples/tutorials/ex34.c.html
src/ksp/ksp/examples/tutorials/ex42.c.html
src/ksp/ksp/examples/tutorials/ex45.c.html