On Tue, Jan 24, 2012 at 6:24 PM, David Warde-Farley <warde...@iro.umontreal.ca> wrote: > On Tue, Jan 24, 2012 at 06:00:05AM +0100, Sturla Molden wrote: >> Den 23.01.2012 22:08, skrev Christoph Gohlke: >> > >> > Maybe this explains the win-amd64 behavior: There are a couple of places >> > in mtrand where array indices and sizes are C long instead of npy_intp, >> > for example in the randint function: >> > >> > <https://github.com/numpy/numpy/blob/master/numpy/random/mtrand/mtrand.pyx#L863> >> > >> > >> >> Both i and length could overflow here. It should overflow on allocation >> of more than 2 GB. >> >> There is also a lot of C longs in the internal state (line 55-105), as >> well as the other functions. >> >> Producing 2 GB of random ints twice fails: > > Sturla, since you seem to have access to Win64 machines, do you suppose you > could try this code: > >>>> a = numpy.ones((1, 972)) >>>> b = numpy.zeros((4993210,), dtype=int) >>>> c = a[b] > > and verify that there's a whole lot of 0s in the matrix, specifically, > >>>> c[574519:].sum() > 356.0 >>>> c[574520:].sum() > 0.0 > > is the case on Linux 64-bit; is it the case on Windows 64?
Yes - I get exactly the same numbers in 64 bit windows with 1.6.1. Cheers Robin _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
