performance - How to measure the speed of a python function

Question

I usually write codes(functions) on www.codefights.com as a competitor.So speed is one of the important part of the code . How can i measure the speed of a certain code in python language whether it is the lambda function or a def function .

Answer 1

Have a look at the timeit module in pythons standard libaray:

https://docs.python.org/2/library/timeit.html

>>> import timeit
>>> timeit.timeit('"-".join(str(n) for n in range(100))', number=10000)
0.8187260627746582
>>> timeit.timeit('"-".join([str(n) for n in range(100)])', number=10000)
0.7288308143615723
>>> timeit.timeit('"-".join(map(str, range(100)))', number=10000)
0.5858950614929199

To give the timeit module access to functions you define, you can pass a setup parameter which contains an import statement:

def test():
    """Stupid test function"""
    L = []
    for i in range(100):
        L.append(i)

if __name__ == '__main__':
    import timeit
    print(timeit.timeit("test()", setup="from __main__ import test"))