Hi, Here is step by step manual for Lanczos implementation:
https://cwiki.apache.org/MAHOUT/dimensional-reduction.html Pavel ________________________________________ От: kuba [[email protected]] Отправлено: 22 ноября 2012 г. 21:34 To: [email protected] Тема: Mahout svd command question Hi, I'm new to hadoop, mahout, and language processing. I'm trying to do LSA (Latent Semantic Analysis) in mahout. I've made my own version of tf-idf matrix building (I know there's seqdirectory and seq2sparse, that can do it for me, but I needed some modifications). I've done 'mahout svd' and I've got output, but don't know how to interpret it. According to books I've read SVD should return three matrices: M = U * Epsilon * (Vt), but 'mahout svd' return only one. I can't find any documentation. Which one does it return, is it U ? Do I have to transpose my tf-idf matrix and compute SVD again to get second matrix ( V )? Also I've found people using: mahout cleansvd what is it for? is there any good documentation?
