On Apr 7, 10:44 am, Robert Kern <robert.k...@gmail.com> wrote: > On 4/7/11 1:40 AM, John Ladasky wrote: > > > On Apr 5, 10:43 am, Philip Semanchuk<phi...@semanchuk.com> wrote: > >> And as Robert Kern pointed out, numpy arrays are also pickle-able. > > > OK, but SUBCLASSES of numpy.ndarray are not, in my hands, pickling as > > I would expect. I already have lots of code that is based on such > > subclasses, and they do everything I want EXCEPT pickle correctly. I > > may have to direct this line of questions to the numpy discussion > > group after all. > > Define the __reduce_ex__() method, not __getstate__(), __setstate__(). > > http://docs.python.org/release/2.6.6/library/pickle.html#pickling-and... > > ndarrays are extension types, so they use that mechanism.
Thanks, Robert, as you can see, I got on that track shortly after I posted my code example. This is apparently NOT a numpy issue, it's an issue for pickling all C extension types. Is there a way to examine a Python object, and determine whether it's a C extension type or not? Or do you have to deduce that from the documentation and/or the source code? I started hunting through the numpy source code last night. It's complicated. I haven't found the ndarray object definition yet. Perhaps because I was looking through .py files, when I actually should have been looking through .c files? -- http://mail.python.org/mailman/listinfo/python-list
