[petsc-dev] strangness in Chebyshev estimate of eigenvalues

[Jed Brown]

Mark Adams <mfadams at lbl.gov> writes:

> Why not just set each index with hash(i) = (i >> 32)^i and forget
> VecSetRandom in here? 

Because if your vertices are numbered lexicographically on a Cartesian
grid, this gives you a plane.  But just put in the legit hash (the one I
linked is pretty good) and then you don't have to worry about
accidentally stumbling upon pathological cases.
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