NumPy Essentials

Hello world in Cython

Cython programs look quite similar to Python ones, mostly with added type information. Let's have a look at a simple program that computes the n ^th Fibonacci number given n:

defcompute_fibonacchi(n): 
    """ 
    Computes fibonacchi sequence 
 
    """ 
 
    a = 1 
    b = 1 
    intermediate = 0  
    for x in xrange(n): 
intermediate = a 
        a = a + b 
        b = intermediate 
    return a 

Let's study this program to understand what is going on under the hood when you call this function with some numeric output; let's say compute_fibonacchi(3).

As we know, Python is an interpreted and dynamic language, which means you do not need to declare variables before using them. This means that, at the start of a function call, the Python interpreter is agnostic about the type of value ...