On Thu, Dec 22, 2011 at 7:51 PM, Jed Brown <jedbrown at mcs.anl.gov> wrote:
> On Thu, Dec 22, 2011 at 19:46, Matthew Knepley <knepley at gmail.com> wrote: > >> dtol failure is impossible for GMRES (and CG). Consider checking with >> that. > > > Well, if you turn of restarts in GMRES and if orthogonalization is working > correctly. > Even if you lose orthogonality, it will just stagnate since you always have the solution from the first few vectors. Likewise, I do not see how you can get an diverging sequence from restarting since you always have the last residual, you just stagnate. Matt -- 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/20111223/db66d7ba/attachment.htm>
