Yeah... having to copy the matrix is a pain in the butt. On Mon, Jan 28, 2013 at 8:13 AM, Ying Liao <[email protected]> wrote:
> A wrapper is needed then because Commons Math takes in and outputs in > different data structure. > > > On Mon, Jan 28, 2013 at 3:14 AM, Sean Owen <[email protected]> wrote: > > > Is it worth simply using the Commons Math implementation? > > > > On Mon, Jan 28, 2013 at 8:04 AM, Sebastian Schelter <[email protected]> > > wrote: > > > This is great news and will automatically boost the performance of all > > > our ALS-based recommenders which are all using QRDecomposition > > internally. > > > > > > On 28.01.2013 04:02, Ted Dunning wrote: > > >> Did that. > > >> > > >> You are right. The QRD in mahout is abysmally slow. I wrote a new > > version > > >> on the airplane that seems to be about 10x faster and still jsut about > > as > > >> accurate (and vastly simpler). I will put up some tests and a patch > in > > the > > >> next week or so. > > > > > >
