SNESSetLineSearchParams

 Sets the parameters associated with the line search routine in the Newton-based method SNESLS.

Synopsis

int SNESSetLineSearchParams(SNES snes,PetscReal alpha,PetscReal maxstep,PetscReal steptol)
Collective on SNES

Input Parameters

snes - The nonlinear context obtained from SNESCreate()
alpha - The scalar such that .5*f_{n+1} . f_{n+1} <= .5*f_n . f_n - alpha |f_n . J . f_n|
maxstep - The maximum norm of the update vector
steptol - The minimum norm fraction of the original step after scaling

Note

Pass in PETSC_DEFAULT for any parameter you do not wish to change.

We are finding the zero of f() so the one dimensional minimization problem we are solving in the line search is minimize .5*f(x_n + lambda*step_direction) . f(x_n + lambda*step_direction)

Contributed by: Mathew Knepley

Keywords

SNES, nonlinear, set, line search params

See Also

SNESGetLineSearchParams(), SNESSetLineSearch()

Level:intermediate
Location:src/snes/impls/ls/lsparams.c
Index of all SNES routines
Table of Contents for all manual pages
Index of all manual pages