I would also be fine with keeping if there is demand. I just proposed to deprecate it and nobody voted against that at that point in time.
--sebastian On 02.08.2013 03:12, Dmitriy Lyubimov wrote: > There's a part of Nathan Halko's dissertation referenced on algorithm page > running comparison. In particular, he was not able to compute more than 40 > eigenvectors with Lanczos on wikipedia dataset. You may refer to that > study. > > On the accuracy part, it was not observed that it was a problem, assuming > high level of random noise is not the case, at least not in LSA-like > application used there. > > That said, i am all for diversity of tools, I would actually be +0 on > deprecating Lanczos, it is not like we are lacking support for it. SSVD > could use improvements too. > > > On Thu, Aug 1, 2013 at 3:15 AM, Fernando Fernández < > fernando.fernandez.gonza...@gmail.com> wrote: > >> Hi everyone, >> >> Sorry if I duplicate the question but I've been looking for an answer and I >> haven't found an explanation other than it's not being used (together with >> some other algorithms). If it's been discussed in depth before maybe you >> can point me to some link with the discussion. >> >> I have successfully used Lanczos in several projects and it's been a >> surprise to me finding that the main reason (according to what I've read >> that might not be the full story) is that it's not being used. At the >> begining I supposed it was because SSVD is supposed to be much faster with >> similar results, but after making some tests I have found that running >> times are similar or even worse than lanczos for some configurations (I >> have tried several combinations of parameters, given child processes enough >> memory, etc. and had no success in running SSVD at least in 3/4 of time >> Lanczos runs, thouh they might be some combinations of parameters I have >> still not tried). It seems to be quite tricky to find a good combination of >> parameters for SSVD and I have seen also a precision loss in some examples >> that makes me not confident in migrating Lanczos to SSVD from now on (How >> far can I trust results from a combination of parameters that runs in >> significant less time, or at least a good time?). >> >> Can someone convince me that SSVD is actually a better option than Lanczos? >> (I'm totally willing to be convinced... :) ) >> >> Thank you very much in advance. >> >> Fernando. >> >
