WHy are you using Lanczos? Why not use something more recent? On Tue, Jul 31, 2012 at 7:00 PM, Aniruddha Basak <[email protected]>wrote:
> Hi, > I am working on Spectral Kmeans which involves an eigen-decomposition step > using Lanczos. As I did not get exact similar results as expected, I tried > to understand the > implementation. > I have one question about "LanczosSolver .java" : > In the "solve" method, while building the "tridiagonal matrix" there is a > step just > after the multiplication job (performed on Hadoop as TimesSquaredJob) as > ------------ > nextVector.assign(new Scale(1.0 / state.getScaleFactor())); > ----------- > I could not understand why this scaling is performed? > > ( When I compared the results on a small matrix to an equivalent Matlab > script, > I found the results are exactly similar WITHOUT this scaling. Including > this scaling > makes the results different from the Matlab results. ) > > > Thanks, > Aniruddha > >
