SNESQNSetScaleType#
Sets the scaling type for the inner inverse Jacobian in SNESQN.
Synopsis#
#include "petscsnes.h"
PetscErrorCode SNESQNSetScaleType(SNES snes, SNESQNScaleType stype)
Logically Collective
Input Parameters#
snes - the nonlinear solver context
stype - scale type
Options Database Key#
-snes_qn_scale_type <diagonal,none,scalar,jacobian> - Scaling type
SNESQNScaleTypes#
SNES_QN_SCALE_NONE- don’t scale the problemSNES_QN_SCALE_SCALAR- use Shanno scalingSNES_QN_SCALE_DIAGONAL- scale with a diagonalized BFGS formula (see Gilbert and Lemarechal 1989), availableSNES_QN_SCALE_JACOBIAN- scale by solving a linear system coming from the Jacobian you provided with SNESSetJacobian() computed at the first iteration of QN and at ever restart.
See Also#
SNES, SNESQN, SNESLineSearch, SNESQNScaleType, SNESSetJacobian()
Level#
intermediate
Location#
Implementations#
SNESQNSetScaleType_QN in src/snes/impls/qn/qn.c
Index of all SNES routines
Table of Contents for all manual pages
Index of all manual pages