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
