Hi all, Attention should be paid to the output of linalg.eig when both matrices are singular. Please find attached a small example. Any comment ? Nils from scipy import * a = diag(arange(0,10)) b = identity(10) b[0,0] = b[0,0]-1 # # Uncomment #w,vr = linalg.eig(a,b) #print w w = linalg.eigvals(a,b) print w Traceback (most recent call last): File "singular.py", line 7, in ? w,vr = linalg.eig(a,b) File "/usr/local/lib/python2.1/site-packages/scipy/linalg/decomp.py", line 108, in eig return _geneig(a1,b,left,right,overwrite_a,overwrite_b) File "/usr/local/lib/python2.1/site-packages/scipy/linalg/decomp.py", line 68, in _geneig vr = _make_complex_eigvecs(w, vr, t) File "/usr/local/lib/python2.1/site-packages/scipy/linalg/decomp.py", line 29, in _make_complex_eigvecs vnew.real = scipy_base.take(vin,ind[::2],1) ValueError: matrices are not aligned for copy