> How is the matrix assembled? > In a deterministic way. > How different? > Not very much. The last residual can vary in its trailing digits, e.g. from 6.5819e-7 to 6.5820e-7 > You should usually not expect deterministic associativity. > Ok, I see. Thanks!
> If your results are sensitive, you may be able to make it deterministic (with > extra work and choice of package), but you should probably reformulate the > problem > > On May 30, 2012 9:21 AM, "Hui Zhang" <mike.hui.zhang at hotmail.com> wrote: > > > I suspect there are some randomness from external matsolverpackage. I use a > > parallel matrix > > as preconditioner, and the preconditioner is exactly LU factored, then I > > saw the KSP (gmres) > > residuals are different from different runs. > > Besides, for sequential matrix, there is no such phenomenon, only for > parallel matrix. > > > > > Is it true of randomness from matsolverpackage? Thanks a lot! > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120530/4d713f18/attachment.html>
