Is it a problem of lapack3.0 of of LinearAlgebra.py? ..................... ==> (Eigenvalues should be (0,2)) >>> a=array([[1,0],[0,1]]) >>> b=array([[0,1],[-1,0]]) >>> M=a+b*complex(0,1.0) >>> Heigenvalues(M) array([-2.30277564, 1.30277564]) >>> print M [[ 1.+0.j 0.+1.j] [ 0.-1.j 1.+0.j]] >>>