dfm/george — pull request #17 by jbernhard (2014-10-07 16:13:35+00:00)
Title: Covariance bug

I found this bug after getting some nonsense posterior covariances. The covariance matrix `Kxs` was being overwritten during calculation.

I added a relevant test. It passes for the basic solver but the last part (positive variance away from training points) fails for HODLR. I am not sure why.