MatSNESMFMoreSetParameters#
Sets the parameters for the approximation of matrix-vector products using finite differences, see MatCreateSNESMFMore()
Synopsis#
#include "petscsnes.h"
PetscErrorCode MatSNESMFMoreSetParameters(Mat mat, PetscReal error, PetscReal umin, PetscReal h)
Input Parameters#
mat - the matrix
error - relative error (should be set to the square root of the relative error in the function evaluations)
umin - minimum allowable u-value
h - differencing parameter
Options Database Keys#
-snes_mf_err <error_rel> - see
MatCreateSNESMF()-snes_mf_umin
- seeMatCreateSNESMF()-snes_mf_compute_err - compute the square root or relative error in function
-snes_mf_freq_err
- set the frequency to recompute the parameters-snes_mf_jorge - use the method of Jorge More
Note#
If the user sets the parameter h directly, then this value will be used
instead of the default computation as discussed in MatCreateSNESMFMore()
See Also#
SNES: Nonlinear Solvers, SNES, MatCreateSNESMF(), MatCreateSNESMFMore()
Level#
advanced
Location#
src/snes/interface/noise/snesmfj2.c
Index of all SNES routines
Table of Contents for all manual pages
Index of all manual pages