[Numpy-discussion] NumPy nogil API

[Stéfan van der Walt]

On Mon, Oct 31, 2011 at 11:28 AM, Zachary Pincus
<zachary.pincus at yale.edu> wrote:
>> As an example, it'd be nice to have scipy.ndimage available without the GIL:
>> http://docs.scipy.org/doc/scipy/reference/ndimage.html
>>
>> Now, this *can* easily be done as the core is written in C++. I'm just
>> pointing out that some people may wish more for calling scipy.ndimage
>> inside their prange than for some parts of NumPy.
>
> Not exactly to your larger point wrt the GIL, but I *think* some skimage (née scikits.image) folks are trying to rewrite most of ndimage's functionality in cython. I don't know what the status of this effort is though...

We still rely on scipy.ndimage in some places, but since we don't have
to support N-dimensional arrays, we can often do things in a slightly
simpler and faster way.  Almost all the performance code in the scikit
is written in Cython, which makes it trivial to release the GIL on
internal loops.

I am actively soliciting feedback from current or prospective users,
so that we can drive the scikit in the right direction.  Already, it's
an entirely different project from what is was a couple of months ago.
 We stopped trying to duplicate the MATLAB toolbox functionality, and
have been adding some exciting new algorithms.  The number of pull
requests have tripled since the 0.3 release, and we're aiming to have
0.4 done this week.

Regards
Stéfan