Hi! There is a casting problem in the 'diag' function:

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a = scipy.array([1,2,3], 'f') scipy.diag(a).typecode() 'd'

while it should be 'f'. The function can be easily patched (only the calls to eye are modified): In file: /home2/scipy/local/lib/python2.3/site-packages/scipy_base/matrix_base.py def diag(v, k=0): """ returns the k-th diagonal if v is a matrix or returns a matrix with v as the k-th diagonal if v is a vector. """ v = asarray(v) s = v.shape if len(s)==1: n = s[0]+abs(k) if k > 0: v = concatenate((zeros(k, v.typecode()),v)) elif k < 0: v = concatenate((v, zeros(-k, v.typecode()))) return eye(n, k=k, typecode=v.typecode())*v elif len(s)==2: v = add.reduce(eye(s[0], s[1], k=k, typecode=v.typecode())*v) if k > 0: return v[k:] elif k < 0: return v[:k] else: return v else: raise ValueError, "Input must be 1- or 2-D." Best, Pietro.