petsc-3.9.4 2018-09-11

KSPSetComputeOperators

set routine to compute the linear operators

Synopsis

#include "petscksp.h" 
PetscErrorCode KSPSetComputeOperators(KSP ksp,PetscErrorCode (*func)(KSP,Mat,Mat,void*),void *ctx)

Logically Collective

Input Arguments

	ksp	- the KSP context
	func	- function to compute the operators
	ctx	- optional context

Calling sequence of func

 func(KSP ksp,Mat A,Mat B,void *ctx)

	ksp	- the KSP context
	A	- the linear operator
	B	- preconditioning matrix
	ctx	- optional user-provided context

Notes: The user provided func() will be called automatically at the very next call to KSPSolve(). It will not be called at future KSPSolve() calls unless either KSPSetComputeOperators() or KSPSetOperators() is called before that KSPSolve() is called.

To reuse the same preconditioner for the next KSPSolve() and not compute a new one based on the most recently computed matrix call KSPSetReusePreconditioner()

Level

beginner

Location

src/ksp/ksp/interface/itfunc.c

Examples