[petsc-dev] Revamping the multilevel KSP interface

[Jed Brown]

On Sat, Mar 17, 2012 at 22:48, Barry Smith <bsmith at mcs.anl.gov> wrote:

> As I noted before to you I did this to have a similar interface for KSP as
> SNES so that people could see the pattern and easily "switch up" to SNES
> from KSP.
>

Okay, but the DM interface _is_ the SNES interface, that callback just
doesn't pass the solver context and doesn't pass a state vector at which to
evaluate the matrix.


>
>  I know you advocate having the user just use SNES if they want this cool
> "SNES-like" behavior.
>
>  Will it kill you to leave this stuff in there? Are you wanting to remove
> it just for philosophical reasons or is it causing trouble to have it?
>

My problem is that I don't like the way PCMG is meddling with DM:

      ierr = DMSetFunction(dms[i],0);
      ierr = DMSetInitialGuess(dms[i],0);

In my model, these pointers will be private to the KSP (they are composed
with the DM, but the DM doesn't know about them), so I guess the meddling
won't be as bad.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20120318/3571decb/attachment.html>