Update NumPy API format to support updates that don't break binary compatibility

The current NumPy API number, stored as NPY_VERSION in the header files, needs to be incremented every time the NumPy C-API changes.  The counter tells developers with exactly which revision of the API they are dealing.  NumPy does some checking to make sure that it does not run against an old version of the API.  Currently, we have no way of distinguishing between changes that break binary compatibility and those that don't.

The proposed fix breaks the version number up into two counters -- one that gets increased when binary compatibility is broken, and another when the API is changed without breaking compatibility.

Backward compatibility with packages such as Matplotlib is maintained by renaming NPY_VERSION to NPY_BINARY_VERSION.

[Andrew Straw, 2008-08-16 07:20:55]

A couple of extremely minor nits.

http://codereview.appspot.com/2946/diff/1/2
File numpy/core/include/numpy/ndarrayobject.h (right):

http://codereview.appspot.com/2946/diff/1/2#newcode43
Line 43: #define NPY_VERSION 0x1000000B
there's no need to change the actual value of NPY_VERSION -- this patch doesn't
change the binary API

http://codereview.appspot.com/2946/diff/1/2#newcode44
Line 44: 
Perhaps move NPY_VERSION below the NPY_BINARY_VERSION stuff rather than above it
to make their relative importance clear

[stefanv, 2008-08-16 07:33:19]

http://codereview.appspot.com/2946/diff/1/2
File numpy/core/include/numpy/ndarrayobject.h (right):

http://codereview.appspot.com/2946/diff/1/2#newcode43
Line 43: #define NPY_VERSION 0x1000000B
On 2008/08/16 07:20:56, Andrew Straw wrote:
> there's no need to change the actual value of NPY_VERSION -- this patch
doesn't
> change the binary API

Thanks, good catch.  This was left over from the general ufuncs patch.

http://codereview.appspot.com/2946/diff/1/2#newcode44
Line 44: 
On 2008/08/16 07:20:56, Andrew Straw wrote:
> Perhaps move NPY_VERSION below the NPY_BINARY_VERSION stuff rather than above
it
> to make their relative importance clear

Done.

[stefanv, 2008-08-16 07:35:08]

Updated with Andrew's suggestions.