What do you see when you run with -ts_view? - Peter
On Thu, Jun 21, 2012 at 9:40 AM, Geoff Oxberry <goxberry at gmail.com> wrote: > Peter, > > Just wanted to make sure there wasn't some Sundials-specific option for > finite difference Jacobians that I was missing; despite reading the manual, > it's a large package, and it's easy to miss things. If that's the case, I'd > like to make a feature request for such an option. > > Geoff > > On Jun 21, 2012, at 9:53 AM, Peter Brune wrote: > > Note that in the code in ts/impls/implicit/sundials it says: > > This uses its own nonlinear solver and krylov method so PETSc SNES and KSP > options do not apply... > > - Peter > On Jun 21, 2012 7:59 AM, "Geoff Oxberry" <goxberry at gmail.com> wrote: > >> Running the following example from PETSC 3.3.0-dev (changeset: >> 23631:0e86ac5e4170) >> >> /path/to/petsc-dev/src/ts/examples/tutorials/ex8 -problem_type rober >> -snes_fd -ts_type sundials >> >> gives the following output >> >> steps 1000 (0 rejected, 0 SNES fails), ftime 744.845, nonlinits 3739, >> linits 3739 >> WARNING! There are options you set that were not used! >> WARNING! could be spelling mistake, etc! >> Option left: name:-snes_fd no value >> >> Just to confirm, is it currently impossible to use a finite difference >> Jacobian matrix in concert with CVODE? If so, could this feature be >> implemented in a future release? I currently rely on Sundials to integrate >> stiff systems of ODEs, and for my application, it is impractical to derive >> an analytical Jacobian matrix. (It is an issue I've discussed both with Jed >> and Matt on another forum.) >> >> Cheers, >> >> Geoff > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120621/e6bc88df/attachment-0001.html>
