[petsc-users] Requesting help with SNES non-linear example

[Vaishak Prasad]

Hi,

Thanks for pointing me to the updated example. The example itself works
fine.

However, on adapting the example to a simple problem ( recovering a given
1D vector), I find that there is only one function call happening and the
solution has not converged. I am attaching the modified example here. Is
there something silly I am doing here?

Any help would be appreciated.

Thanks and Regards


On Sat, Oct 26, 2024 at 12:42 PM Jose E. Roman <jroman at dsic.upv.es> wrote:

> The examples in those old slides might be outdated. Try with the examples
> that come with the PETSc repo or tarball. In particular, that example can
> be found in src/binding/petsc4py/demo/legacy/bratu2d/bratu2d.py.
>
> Jose
>
> > El 25 oct 2024, a las 19:58, Vaishak Prasad <vaishakprasad at gmail.com>
> escribió:
> >
> > Dear All,
> > Greetings from India.
> >
> > I am new to petsc4py. I was trying out the example on slides 18, and 19
> at
> >
> > https://urldefense.us/v3/__https://www.bu.edu/pasi/files/2011/01/Lisandro-Dalcin-petsc4py.pdf__;!!G_uCfscf7eWS!crzDSnMPvGJ19hJ6wP30I5DQnV7XMkJmxebYeLV9MFjpkLL2d5VtXHhHE2si93mzUmxzKxeVo0dkoyx-Cd04hRPUqrAd$ 
> >
> > However, I get a zero vector for the solution `x`.
> >
> > I am using petsc4py 3.21.3 on Linux.
> >
> > Any help would be appreciated.
> >
> > With regards
> >
> > --
> > Vaishak Prasad
> > Post Doctoral Fellow
> > Astrophysical Relativity Group
> > International Center for Theoretical Sciences
> > Tata Institute of Fundamental Research
> > Survey No. 151, Shivakote, Hesaraghatta Hobli,
> > Bengaluru, Karnataka, India,
> > Earth, Solar system,
> > Milky Way Galaxy, The Local Group
>
>

-- 
Vaishak Prasad
Post Doctoral Fellow
Astrophysical Relativity Group
International Center for Theoretical Sciences
Tata Institute of Fundamental Research
Survey No. 151, Shivakote, Hesaraghatta Hobli,
Bengaluru, Karnataka, India,
Earth, Solar system,
Milky Way Galaxy, The Local Group
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