There was a variant of cholesky decomposition in Mahout at one time not so
long ago. I would guess that it is still there.
It is difficult to make a truly distributed version of QR decomposition,
but for the purposes of the randomized SVD in Mahout, it wasn't actually
necessary to have a true QR.
I don't have a pointer handy and I am not even sure that this code is still
Sorry about that.
On Wed, Apr 18, 2018 at 7:08 PM, QIFAN PU <[EMAIL PROTECTED]> wrote: