I've been trying to write a Python C extension module that uses NumPy
and has a subtype of numpy.ndarray written in C. However, I've run into
a snag: calling numpy.ndarray.__new__(mysubtype, ...) triggers an
exception in the bowels of Python (this is necessary for a handful of
NumPy features).
On 5/2/2010 4:34 AM, Carl Banks wrote:
Why don't you use mysubtype.__new__(mysubtype,...)?
If you wrote mysubtype in C, and defined a different tp_new than
ndarray, then this exception will trigger. And it ought to; you don't
want to use ndarray's tp_new to create an object of your subclass,
On 5/2/2010 1:43 PM, Robert Kern wrote:
Perhaps things would be clearer if you could post the C code that you've
written that fails. So far, you've only alluded at what you are doing
using Python-syntax examples.
I'm not sure how much this will help, but here you go. The actual C code
On 5/2/2010 3:58 PM, Robert Kern wrote:
Well, I think we can change zeros_like() and the rest to work around
this issue. Can you bring it up on the numpy mailing list?
def zeros_like(a):
if isinstance(a, ndarray):
res = numpy.empty(a.shape, a.dtype, order=a.flags.fnc)
res.fill(0)
res =
