petsc-3.9.4 2018-09-11
SNESKSPGetUseEW
Gets if SNES is using Eisenstat-Walker method for computing relative tolerance for linear solvers within an inexact Newton method.
Synopsis
#include "petscsnes.h"
PetscErrorCode SNESKSPGetUseEW(SNES snes, PetscBool *flag)
Not Collective
Input Parameter
snes -SNES context
Output Parameter
flag -PETSC_TRUE or PETSC_FALSE
Notes
Currently, the default is to use a constant relative tolerance for
the inner linear solvers. Alternatively, one can use the
Eisenstat-Walker method, where the relative convergence tolerance
is reset at each Newton iteration according progress of the nonlinear
solver.
Reference
S. C. Eisenstat and H. F. Walker, "Choosing the forcing terms in an
inexact Newton method", SISC 17 (1), pp.16-32, 1996.
Keywords
SNES, KSP, Eisenstat, Walker, convergence, test, inexact, Newton
See Also
SNESKSPSetUseEW(), SNESKSPGetParametersEW(), SNESKSPSetParametersEW()
Level
advanced
Location
src/snes/interface/snes.c
Index of all SNES routines
Table of Contents for all manual pages
Index of all manual pages