On Tue, Nov 11, 2008 at 12:41 PM, James Philbin <philbinj@gmail.com> wrote:

> Can you try checking the functions log1p and exp separately for all three
> floating types? Something like

Well, log1p seems to be the culprit:

>>> import numpy as np
>>> np.log1p(np.ones(1,dtype='f')*3)

... hangs here ...

exp is fine:

>>> import numpy as np
>>> np.exp(np.ones(1,dtype='f')*3)
array([ 20.08553696], dtype=float32)

If it helps:
$ uname -a
Linux lewis 2.6.27-7-generic #1 SMP Tue Nov 4 19:33:06 UTC 2008 x86_64 GNU/Linux

My guess is that this is a libm/gcc problem on x86_64, perhaps depending on the flags libm was compiled with. What distro are you using? I'm not sure how to handle this without some ugly voodoo in the numpy build process. We currently check if the library functions are present, but we have no way to mark them as present but buggy.

Can you try plain old log/log10 also? I'll try to put together some c code you can use to check things also so that you can file a bug report with the distro if the problem persists.

Chuck