SNESSetFunction#

Sets the function evaluation routine and function vector for use by the SNES routines in solving systems of nonlinear equations.

Synopsis#

#include "petscsnes.h"  
PetscErrorCode SNESSetFunction(SNES snes, Vec r, PetscErrorCode (*f)(SNES, Vec, Vec, void *), void *ctx)

Logically Collective

snes - the SNES context
r - vector to store function values, may be NULL
f - function evaluation routine; see SNESFunction for calling sequence details
ctx - [optional] user-defined context for private data for the function evaluation routine (may be NULL)