[petsc-dev] strangness in Chebyshev estimate of eigenvalues

[Jed Brown]

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