Hi, It turns out you're running into a bit-error. In general, the two's complement of -2 ** (n-1) with the bit-length being limited to n bits is itself... No way around that. And integers don't set hardware exceptions so checking for errors like these is hard as well.
TL;DR: It's an error with how the integer is stored in memory and how you're running out of space. Regards, Hameer Abbasi On 03.07.19, 17:03, "NumPy-Discussion on behalf of Nicolas Rougier" <numpy-discussion-bounces+einstein.edison=gmail....@python.org on behalf of nicolas.roug...@inria.fr> wrote: Hi, I’m a bit surprised with the following code: >>> import numpy as np >>> np.seterr(all='warn') >>> Z = np.array([-128], dtype=np.byte) >>> print(np.abs(Z)) [-128] Obviously, it does not return the absolute value and I get no warning. Is it something expected ? (numpy 1.16.4, python 3.7.3) Nicolas _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@python.org https://mail.python.org/mailman/listinfo/numpy-discussion _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@python.org https://mail.python.org/mailman/listinfo/numpy-discussion