Comment by threeducks

A while ago, I also implemented a dense eigenvalue solver in Python following a similar approach, but found that it did not converge in O(n^3) as sometimes claimed in literature. I then read about the Divide-and-conquer eigenvalue algorithm, which did the trick. It seems to have a reasonable Wikipedia page these days: https://en.wikipedia.org/wiki/Divide-and-conquer_eigenvalue_...