PetscErrorCode PETSCSNES_DLLEXPORT SNESLineSearchSet(SNES snes,PetscErrorCode (*func)(SNES,void*,Vec,Vec,Vec,Vec,Vec,PetscReal,PetscReal*,PetscReal*,PetscTruth*),void *lsctx)
| snes | - nonlinear context obtained from SNESCreate() | |
| lsctx | - optional user-defined context for use by line search | |
| func | - pointer to int function |
Collective on SNES
| SNESLineSearchCubic() | - default line search | |
| SNESLineSearchQuadratic() | - quadratic line search | |
| SNESLineSearchNo() | - the full Newton step (actually not a line search) | |
| SNESLineSearchNoNorms() | - the full Newton step (calculating no norms; faster in parallel) |
| -snes_ls [cubic,quadratic,basic,basicnonorms] | - Selects line search | |
| -snes_ls_alpha <alpha> | - Sets alpha | |
| -snes_ls_maxstep <max> | - Sets maxstep | |
| -snes_ls_steptol <steptol> | - Sets steptol, this is the minimum step size that the line search code will accept; min p[i]/x[i] < steptol. The -snes_stol <stol> is the minimum step length the default convergence test will use and is based on 2-norm(p) < stol*2-norm(x) |
func (SNES snes,void *lsctx,Vec x,Vec f,Vec g,Vec y,Vec w,
PetscReal fnorm,PetscReal *ynorm,PetscReal *gnorm,PetscTruth *flag)
| snes | - nonlinear context | |
| lsctx | - optional user-defined context for line search | |
| x | - current iterate | |
| f | - residual evaluated at x | |
| y | - search direction | |
| w | - work vector | |
| fnorm | - 2-norm of f |
| g | - residual evaluated at new iterate y | |
| w | - new iterate | |
| gnorm | - 2-norm of g | |
| ynorm | - 2-norm of search length | |
| flag | - set to PETSC_TRUE if the line search succeeds; PETSC_FALSE on failure. |
Level:advanced
Location:src/snes/impls/ls/ls.c
Index of all SNES routines
Table of Contents for all manual pages
Index of all manual pages