[petsc-users] DMDA questions

[Matthew Knepley]

On Wed, Mar 5, 2014 at 12:54 PM, Xiangdong <epscodes at gmail.com> wrote:

> If I first define a DM, and obtain the solution vector on this DM (through
> non multigrid method).  However, given that this DM is so fine, I may only
> need to save/view the solution on a coarsen grid. Is there some functions
> available in petsc for this instead of writing my own vec scatter?
>

Interpolation between general DMs does not make sense because we do not
prescribe anything
about the function representation. DMDA has interpolation routines, and so
does DMPlex.

   Matt


> Thank you.
>
> Xiangdong
>
>
> On Mon, Mar 3, 2014 at 9:58 PM, Jed Brown <jed at jedbrown.org> wrote:
>
>> Xiangdong <epscodes at gmail.com> writes:
>> > Could you please expand it a little more on using DMCoarsenHookAdd to
>> > restrict a fine vector on a coarse grid? The only example I can find is
>> > ex48 in snes. It is not clear how the coarsen vector are generated from
>> > that example.
>>
>> Look at the use in src/ts/impls/implicit/theta/theta.c
>>
>
>


-- 
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/20140305/4604b358/attachment.html>