#NEWLINE# def _sym_decorrelation( W ) : #NEWLINE# #INDENT# ' Symmetric decorrelation\n    i.e. W <- (W * W.T) ^{-1/2} * W\n    ' #NEWLINE# ( s , u ) = linalg . eigh ( np . dot ( W , W . T ) ) #NEWLINE# return np . dot ( np . dot ( ( u * ( 1.0 / np . sqrt ( s ) ) ) , u . T ) , W )