Hi, In my Cython code a function processes it argument x as follows: x_arr = PyArray_CheckFromAny( x, NULL, 0, 0, cnp.NPY_ELEMENTSTRIDES | cnp.NPY_ENSUREARRAY | cnp.NPY_NOTSWAPPED, NULL) if x_arr is not x: in_place = 1 # a copy was made, so we can work in place. The logic is of the last line turns out to be incorrect, because the input x can be a class with an array interface: class FakeArray(object): def __init__(self, data): self._data = data self.__array_interface__ = data.__array_interface__ Feeding my function FakeArray(xx), x_arr will point into the content of xx, resulting in unwarranted content
I am trying to replace that condition with if x_arr is not x and cnp.PyArray_Check(x): # a copy was made, so we can work in place. in_place = 1 if cnp.PyArray_CHKFLAGS(x_arr, cnp.NPY_WRITEABLE) else 0 I am wondering if I perhaps overlooked some case. Thank you, Sasha _______________________________________________ NumPy-Discussion mailing list [hidden email] https://mail.scipy.org/mailman/listinfo/numpy-discussion |
Sat, 12 Nov 2016 17:00:07 +0000, Pavlyk, Oleksandr kirjoitti:
[clip] > if x_arr is not x: > in_place = 1 # a copy was made, so we can work in place. > > The logic is of the last line turns out to be incorrect, because the > input x can be a class with an array interface. Please see: https://github.com/scipy/scipy/blob/master/scipy/linalg/misc.py#L169 This probably can be translated to equivalent Numpy C API calls. _______________________________________________ NumPy-Discussion mailing list [hidden email] https://mail.scipy.org/mailman/listinfo/numpy-discussion |
In reply to this post by Pavlyk, Oleksandr
I tend to use ndarray.copy() in python code -- no reason you couldn't do the same in Cython. If you want to take any array-like object that may not have a copy() method, you could call asanyarray() first: -CHB On Sat, Nov 12, 2016 at 9:00 AM, Pavlyk, Oleksandr <[hidden email]> wrote:
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