SNESLineSearchSetDamping#

Sets the line search damping parameter.

Synopsis#

#include "petscsnes.h" 
PetscErrorCode SNESLineSearchSetDamping(SNESLineSearch linesearch, PetscReal damping)

Input Parameters#

linesearch - the line search context
damping - The damping parameter

Options Database Key#

-snes_linesearch_damping - the damping value

Note#

The SNESLINESEARCHNONE line search merely takes the update step scaled by the damping parameter. The use of the damping parameter in the SNESLINESEARCHL2 and SNESLINESEARCHCP line searches is much more subtle; it is used as a starting point in calculating the secant step. However, the eventual step may be of greater length than the damping parameter. In the SNESLINESEARCHBT line search it is used as the maximum possible step length, as the SNESLINESEARCHBT line search only backtracks.

Level#

intermediate

Location#

src/snes/linesearch/interface/linesearch.c

Index of all SNES routines
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