danieleb@3: function [x n] = normcol(x)
danieleb@3: %NORMCOL normalise the columns to unit length
danieleb@3: %
danieleb@3: % [x n] = normcol(x)
danieleb@3: %
danieleb@3: % normalises the columns of the input matrix x and returns a vector n
danieleb@3: % containing the initial norm of the columns.
danieleb@3: %
danieleb@3: % ----------------------------------------------------------- %
danieleb@3: %  Daniele Barchiesi, daniele.barchiesi@eecs.qmul.ac.uk       %
danieleb@3: %  Centre for Digital Music, Queen Mary University of London  %
danieleb@3: %  Apr. 2011                                                  %
danieleb@3: % ----------------------------------------------------------- %
danieleb@3: n = sqrt(sum(conj(x).*x,1));
danieleb@3: x = x*diag(1./n);