Folks, np.linalg.lstsq of a random-uniform A 50 x 32 with 3 columns all 0 returns x[:3] 0 as expected, but 4 columns all 0 => huge x: lstsq (50, 32) with 4 columns all 0: [ -3.7e+09 -3.6e+13 -1.9e+13 -2.9e+12 7.3e-01 ...
This may be a roundoff problem, or even a Mac Altivec lapack bug, not worth looking into. linalg.svd is ok though, odd. Summary: if you run linalg.lstsq on big arrays, either check max |x| or regularize, do lstsq( vstack( A, weight * eye(dim) ), hstack( b, zeros(dim) )) cheers -- denis _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion