Iterate through NumPy arrays in Cython, not Python. ... Note that you don’t need to specify the memory layout in the declaration, as that’s detected automatically.

As noted above, NumPy arrays behave a lot like other Python objects, for the sake of convenience. For instance, they can be indexed like lists; arr[0] accesses the first element of a NumPy array.

This NumPy version performs admirably, clocking in at around 28.77 ns per element -- almost two times faster than the pure Python rendition. Comparison established -- we have a clear winner. However, ...

Gommers added, "Really long-term I expect the NumPy 'execution engine' (i.e., the C and Python code that does the heavy lifting for fast array operations) to become less and less relevant, and the ...