#include "petscmat.h" PetscErrorCode PETSCMAT_DLLEXPORT MatMFFDSetFunctionError(Mat mat,PetscReal error)Collective on Mat
| mat | - the matrix free matrix created via MatCreateMFFD() or MatCreateSNESMF() | |
| error_rel | - relative error (should be set to the square root of the relative error in the function evaluations) |
| -mat_mffd_err <error_rel> | - Sets error_rel |