[Numpy-discussion] [RFE] Suport for version 3 of array protocol in numarray

[Travis Oliphant]

Francesc Altet wrote:
> Hi,
>
> I've lately ran into problems in numarray-->numpy conversions which are due to 
> a lack of suport of the array procol version 3 on behalf of numarray. For 
> more info on this issue see:
>
> http://projects.scipy.org/scipy/numpy/ticket/256
>
> and
>
> http://projects.scipy.org/scipy/numpy/ticket/266
>
> Question: is the numarray crew going to add this support anytime soon? If not, 
> I'd advocate to retain support for version 2 in NumPy at least for sometime 
> (until numarray gets the support), although I don't know whether this will 
> complicate things a lot in NumPy.
>
> I personally don't need this functionality as I've found a workaround for 
> PyTables (i.e. using the numpy.ndarray factory in order to create the NumPy 
> object directly from the numarray buffer), but I think this would be very 
> useful in helping other users (end-users mainly) in the numarray-->NumPy 
> transition.
>   

Remember it's only the Python-side of version 2 of the protocol that is 
not supported.  The C-side is still supported.  Thus, it's only objects 
which don't export the C-side of the interface that are affected.  In 
numarray that is the chararray and the recarray.  Normal numarray arrays 
should work fine as the C-side of version 2  is still supported.

I think the number of objects supporting the Python side of version 2 of 
the protocol is small enough that it is not worth the extra hassle (and 
attribute lookup time) in NumPy to support it.

It would be a good thing if numarray supported version 3 of the protocol 
by adding  the __array_interface__ attribute to support the Python side 
of version 3.

-Travis