[petsc-users] Parallel ODE solver

[Sahai, Amal]

I was able to get a simple time dependent ODE running in parallel using the time-stepper in Petsc. I had a follow up question regarding this: For my original problem I can provide the RHS function but have no way of computing the Jacobian analytically and then storing it using DMTSSetIJacobianLocal. How can I compute the Jacobian numerically by just supplying the RHS function to Petsc without having to manually perturb and generate individual elements in the Jacobian myself?

Thanks!

Regards
Amal
________________________________________
From: Patrick Sanan [patrick.sanan at gmail.com]
Sent: Tuesday, October 20, 2015 4:34 AM
To: Julian Andrej
Cc: Sahai, Amal; petsc-users at mcs.anl.gov
Subject: Re: [petsc-users] Parallel ODE solver

Further note that you can use sundials from within PETSc, without any
more hassle than supplying a configure flags (--download-sundials, or
see the other entries under SUNDIALS: with ./configure --help).
That could potentially be very helpful in moving to TS.

http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/TS/TSSUNDIALS.html


On Tue, Oct 20, 2015 at 09:21:04AM +0200, Julian Andrej wrote:
> There are a variety of algorithms for ODE/DAEs in the PetscTS
> implementation. For examples see e.g.
> http://www.mcs.anl.gov/petsc/petsc-current/src/ts/examples/tutorials/index.html
>
> Sundials is also capable of parallel solving, even from the Matlab
> sundialsTB interface, as far as i know.
>
> On Tue, Oct 20, 2015 at 9:10 AM, Sahai, Amal <sahai2 at illinois.edu> wrote:
> > I am trying to solve a very large system of ODEs for modeling the
> > time-varying composition of a homogeneous (no spatial variation) reaction
> > mixture composed of 50000 species. I was wondering if there is parallel ode
> > solver included in PETSc? I have been using the sundials package for solving
> > a smaller system in serial and would like to move on to parallel framework
> > to speed up my calculations.
> >
> > Regards
> > Amal