On Fri, Mar 25, 2011 at 10:21 AM, Pauli Virtanen <pav@iki.fi> wrote:
The buffer interface cannot be used to export the half-float types, since the type is not specified in PEP 3118. Numpy cannot unilaterally add nonstandard format codes to the spec.
What can be done instead is exporting the half-float items (and any other non-3118 types) as plain bytes. I think this is the way to go.
What about as uint16s? Won't plain bytes have endian issues? case NPY_HALF: if (_append_char(str, 'H')) return -1; break; Something like that? I am also still curious about where unit tests for things like this should go.
On the Cython side, you'd need to detect when you are working with Numpy arrays, and get the half-float type information from the Numpy dtype rather than from the exported buffer.
Hrm, okay. I'll have to follow up with the Cython folks about that. I hope that my fears about that ending up being a sweeping change are unfounded (having already gone through and made the changes to unilaterally add support for 'e' buffer types, it seems like it's baked in; we'll see). :-/ Thanks, Eli