On 06/01/2011 11:01 AM, Robert Kern wrote: > On Wed, Jun 1, 2011 at 10:44, Craig Yoshioka<[email protected]> wrote: >> would anyone object to fixing the numpy mean and stdv functions, so that >> they always used a 64-bit value to track sums, or so that they used a >> running calculation. That way >> >> np.mean(np.zeros([4000,4000],'f4')+500) >> >> would not equal 511.493408? > Yes, I object. You can set the accumulator dtype explicitly if you > need it: np.mean(arr, dtype=np.float64) > Sure but fails to address that the output dtype of mean in this case is np.float64 which one would naively assume is also np.float64: >>> np.mean(np.zeros([4000,4000],'f4')+500).dtype dtype('float64')
Thus, we have: Tickets 465 and 518 http://projects.scipy.org/numpy/ticket/465 http://projects.scipy.org/numpy/ticket/518 Various threads as well such as: http://mail.scipy.org/pipermail/numpy-discussion/2010-December/054253.html Bruce _______________________________________________ NumPy-Discussion mailing list [email protected] http://mail.scipy.org/mailman/listinfo/numpy-discussion
