Integer overflow in numpy arrays

Question

import numpy as np
a = np.arange(1000000).reshape(1000,1000)
print(a**2)

With this code I get this answer. Why do I get negative values?

Answer 1

A solution to this problem is as follows (taken from here):

...change in class StringConverter._mapper (numpy/lib/_iotools.py) from:

{{{
 _mapper = [(nx.bool_, str2bool, False),
            (nx.integer, int, -1),
            (nx.floating, float, nx.nan),
            (complex, _bytes_to_complex, nx.nan + 0j),
            (nx.string_, bytes, asbytes('???'))]
}}}

to

{{{
 _mapper = [(nx.bool_, str2bool, False),
            (nx.int64, int, -1),
            (nx.floating, float, nx.nan),
            (complex, _bytes_to_complex, nx.nan + 0j),
            (nx.string_, bytes, asbytes('???'))]
 }}}

This solved a similar problem that I had with numpy.genfromtxt for me

Note that the author describes this as a 'temporary' and 'not optimal' solution. However, I have had no side effects using v2.7 (yet?!).