So, I know that MAHOUT-369 fixed a bug with the distributed version of the
LanczosSolver but I am experiencing a similar problem with the
non-distributed version.

I send a dataset of gaussian distributed numbers (testing PCA stuff) and
my eigenvalues are seemingly reversed. Below I have the output given in
the logs from LanczosSolver.

Output:
INFO: Eigenvector 0 found with eigenvalue 0.0
INFO: Eigenvector 1 found with eigenvalue 347.8703086831804
INFO: LanczosSolver finished.

So it returns a vector with eigenvalue 0 before one with an eigenvalue of
347?. Whats more interesting is that when I increase the rank, I get a new
eigenvector with a value between 0 and 347:

INFO: Eigenvector 0 found with eigenvalue 0.0
INFO: Eigenvector 1 found with eigenvalue 44.794928654801566
INFO: Eigenvector 2 found with eigenvalue 347.8286920203704

Shouldn't the eigenvalues be in descending order? Also is the 0.0
eigenvalue even valid?

Thanks,
Trevor

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