On Dec 13, 2012, at 11:27 AM, Peter Brune <prbrune at gmail.com> wrote:
> An abandoned attempt at this lies dormant in src/snes/impls/multiblock. We > could try to revive it. Or at least give it a reasonable name :-( like SNESFIELDSPLIT > > - Peter > > > On Thu, Dec 13, 2012 at 11:25 AM, Jed Brown <jedbrown at mcs.anl.gov> wrote: > Yes, but even more than linear fieldsplit, there are _many_ variations, > involving nonlinear change of basis and various types of elimination. I worry > that it may be even more complicated and harder to use. > > > On Thu, Dec 13, 2012 at 9:15 AM, Barry Smith <bsmith at mcs.anl.gov> wrote: > > We could possibly provide the equivalent of PCFieldSplit for nonlinear > problems? These could be accelerated via the various non-linear accelerates > or even via matrix-free Newton? > > > Barry > > > Begin forwarded message: > >> From: Jed Brown <jedbrown at mcs.anl.gov> >> Subject: Re: Is there any example that allows time-integration provided by >> users >> Date: December 13, 2012 11:06:29 AM CST >> To: Lulu Liu <lulu.liu at kaust.edu.sa>, Barry Smith <bsmith at mcs.anl.gov> >> >> It sounds like you want to do classical operator splitting (which is >> notoriously inaccurate). The literature on these methods is rife with >> special-purpose band-aids that I'd rather not try to support all of in PETSc. >> >> My preference would be to write your method as an ARKIMEX, with "trivial" >> implicit part on the "part" of the equation that you wanted to treat >> explicitly, or if you wanted to solve both implicitly (but decoupled) then >> do the appropriate incomplete solve. Can you be more specific about what >> problem you want to solve? >> >> >> On Wed, Dec 12, 2012 at 7:42 AM, Lulu Liu <lulu.liu at kaust.edu.sa> wrote: >> There is two equations in my system, and I want solve the first one, and >> then solve the second equation. Is there any example that allows me to solve >> equations one by one? >> >> >> I want to solve nonlinear system on every time level, but it is feasible if >> I could provide the time discretization schemes by myself. Is there any >> example about this? >> >> Thank you! >> >> -- >> Best wishes, >> Lulu Liu >> Applied Mathematics and Computational Science >> King Abdullah University of Science and Technology >> Tel??966?0544701599 >> >> >> This message and its contents, including attachments are intended solely for >> the original recipient. If you are not the intended recipient or have >> received this message in error, please notify me immediately and delete this >> message from your computer system. Any unauthorized use or distribution is >> prohibited. Please consider the environment before printing this email. >> > > >
