This example for using the C-API with NumPy is for python 3.x only --

the interface for python 2.x is different. Note that this was written

to use the latest API.

reference: http://scipy-lectures.github.io/advanced/interfacing_with_c/interfacing_with_c.html

http://wiki.scipy.org/Cookbook/C_Extensions/NumPy_arrays

to build:

python3 setup.py build_ext --inplace

to run:

>>> import numpy_in_c

>>> help (numpy_in_c)

>>> import numpy as np

>>> a = np.arange(20, dtype=np.float64)

>>> a.shape = (4,5)

>>> print a

[[ 0. 1. 2. 3. 4.]

[ 5. 6. 7. 8. 9.]

[ 10. 11. 12. 13. 14.]

[ 15. 16. 17. 18. 19.]]

>>> b = numpy_in_c.example(a)

>>> print b

[[ 0. 1. 4. 9. 16.]

[ 25. 36. 49. 64. 81.]

[ 100. 121. 144. 169. 196.]

[ 225. 256. 289. 324. 361.]]