Actual output: >>> from numpy import linalg as LA >>> LA.eig(np.diag((1,2,3))) (array([ 1., 2., 3.]), array([[ 1., 0., 0.], [ 0., 1., 0.], [ 0., 0., 1.]])) i.e., a line feed wasn't inserted between w and v. Bug? DG