[Numpy-discussion] Fortran ordering
Stéfan van der Walt
stefan@sun.ac...
Sat Apr 17 12:50:22 CDT 2010
On 16 April 2010 21:35, Paul Northug <pnorthug@gmail.com> wrote:
> how is it stored in memory, as [1, 2, 3, 4] or [1, 3, 2, 4]?
The latter:
In [22]: np.fromstring(str(x.data))
Out[22]: array([ 1., 3., 2., 4.])
> But when I call external libraries through ctypes with a.ctypes.data
> as argument, the external function gets [1, 2, 3, 4] (I think).
That should not be the case. Please see the attached code as a
demonstration, which has the following output:
Printing values as in memory:
1 3 2 4
Let's assign values 0, 1, 2 and 3 to consecutive memory
addresses. The result is:
[[ 0. 2.]
[ 1. 3.]]
Regards
Stéfan
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