Hi, On Tue, Apr 30, 2013 at 8:08 PM, Yaroslav Halchenko <lists@onerussian.com> wrote:
could anyone on 32bit system with fresh numpy (1.7.1) test following:
wget -nc http://www.onerussian.com/tmp/data.npy ; python -c 'import numpy as np; data1 = np.load("/tmp/data.npy"); print np.sum(data1[1,:,0,1]) - np.sum(data1, axis=1)[1,0,1]'
0.0
because unfortunately it seems on fresh ubuntu raring (in 32bit build only, seems ok in 64 bit... also never ran into it on older numpy releases):
python -c 'import numpy as np; data1 = np.load("/tmp/data.npy"); print np.sum(data1[1,:,0,1]) - np.sum(data1, axis=1)[1,0,1]' -1.11022302463e-16
PS detected by failed tests of pymvpa
Reduced case on numpy 1.7.1, 32-bit Ubuntu 12.04.2 In [64]: data = np.array([[ 0.49505185, 0.47212842], [ 0.53529587, 0.04366172], [-0.13461665, -0.01664215]]) In [65]: np.sum(data[:, 0]) - np.sum(data, axis=0)[0] Out[65]: 1.1102230246251565e-16 No difference for single vector: In [4]: data1 = data[:, 0:1] In [5]: np.sum(data1[:, 0]) - np.sum(data1, axis=0)[0] Out[5]: 0.0 Puzzling to me... Cheers, Matthew