When you call the Cython function in your Python code, send the entire NumPy array object as an argument for that function call. Perform all the iteration over the object in Cython.

Python loves iteration and encourages you to use for loops wherever you can. In many cases, it's easiest to express your iterator in the form of a function, known in the Python world as a "generator ...

Dr. James McCaffrey of Microsoft Research shows how to implement simulated annealing for the Traveling Salesman Problem (find the best ordering of a set of discrete items).