[Numpy-tickets] [NumPy] #1030: C function PyArray_New seems to ignore the 'strides' argument.
NumPy
numpy-tickets@scipy....
Fri Feb 27 04:04:10 CST 2009
#1030: C function PyArray_New seems to ignore the 'strides' argument.
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Reporter: alexis.roche | Owner: somebody
Type: defect | Status: new
Priority: highest | Milestone: 1.3.0
Component: Other | Version: none
Severity: normal | Keywords:
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I create the following two arrays as follows:
X = np.asarray([[0,1,2],[3,4,5]]).astype('uint8')
x = X[:, 0] ## x == array([0, 3])
I then pass X to a C routine that attempts to create another view on
X[:,0] using:
npy_intp dim[1] = {2};
npy_intp strides[1] = {3};
int itemsize = 1;
PyArrayObject* y = (PyArrayObject*) PyArray_New(&PyArray_Type, 1, dim,
type, strides,
(void*)PyArray_DATA(X),
itemsize, NPY_CARRAY, NULL);
While I expect y to be equal to x, the result is array([ 0, 1]), which
would have been the expected result if I had set the 'strides' argument to
1. I am running numpy version 1.3.0.dev6468.
I have been using PyArray_New for 3 years in similar context with devel
versions of numpy, and only caught that weird behavior recently.
--
Ticket URL: <http://scipy.org/scipy/numpy/ticket/1030>
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