[petsc-dev] strangness in Chebyshev estimate of eigenvalues

[Matthew Knepley]

On Tue, May 17, 2016 at 2:11 PM, Jed Brown <jed at jedbrown.org> wrote:

> Barry Smith <bsmith at mcs.anl.gov> writes:
> >   Sounds like Jed is saying he is ok with making the default use the
> >   random number generator. Do this in a branch and be aware that you
> >   have to update a bunch of the test output files to match the new
> >   convergence histories introduced by the change.
>
> Sure, but if it's all the same to you all, let's use a hash.  This guy
> seems to have a convenient permutation of 32-bit integers.  (Overkill
> for us, but that's not a problem.)
>
> http://stackoverflow.com/a/12996028/33208
>
> Use i=(i >> 32)^i for 64-bit input.
>

Should we just make this another Random implementation which is only for
testing?

  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
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