[petsc-users] SNES line search basic

[Matthew Knepley]

On Tue, Oct 22, 2013 at 2:18 AM, Gong Ding <gdiso at ustc.edu> wrote:

> Hi,
> I updated petsc from 3.2 to 3.4. However, I found that the nonlinear
> solver previously worked well now failed with massage DIVERGED_LINE_SEARCH.
> My problem is extremely nonlinear, cubic line search may fail but Newton
> method works.
>
> With petsc 3.2, I only use basic Newton by calling
> SNESLineSearchSet(snes, SNESLineSearchNo, PETSC_NULL)
> With 3.4 I call basic Newton by
> SNESLineSearchSetType(snes, SNESLINESEARCHBASIC).
>
> However, petsc 3.4 still reports
> [0] SNESSolve_NEWTONLS(): fnorm=3.7500000000000006e-02,
> gnorm=3.7500000000000006e-02, ynorm=1.0000000000000000e+00, lssucceed=0
> [0] SNESNEWTONLSCheckLocalMin_Private(): || J^T F|| 1.414213562373e+00
> near zero implies found a local minimum
>
>
> It seems petsc 3.4 can not disable line search. Does anyone have the same
> problem?


Send -snes_view

   Matt


>
> Gong Ding
>
>
>
>


-- 
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to which their
experiments lead.
-- Norbert Wiener
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20131022/7d5e8e14/attachment.html>