[petsc-dev] strangness in Chebyshev estimate of eigenvalues

[Mark Adams]

On Wed, Aug 26, 2015 at 3:30 PM, Jed Brown <jed at jedbrown.org> wrote:

> Mark Adams <mfadams at lbl.gov> writes:
> > I really think that it does not matter.  Just as long as it is noisy.
> IMO,
> > but we have no data, and I'm not sure how we could study it.  What is the
> > chance that your generator will generate a low frequency vector on some
> god
> > knows what grid?  I can not imaging this happening ... and I'm not sure
> how
> > I could even generate data to 'prove' it.
>
> Your hokey hash function generates stripes of various sorts on grids
> with leading dimension 51, 100, and other combinations.


You know there are more prime number, 100% of them are larger.

What do you want to do?

If dran48 is one line then I can just copy that and move on.



> For an
> anisotropic operator aligned to the grid, that would be devastatingly
> low energy.
>
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