Title: Test Code Speed
Slug: test_code_speed
Summary: Test Code Speed in Python. Date: 2016-01-23 12:00
Category: Python
Tags: Testing
Authors: Chris Albon

Interesting in learning more? Here are some good books on unit testing in Python: Python Testing: Beginner's Guide and Python Testing Cookbook.

Preliminaries



In [1]:

    
import cProfile

Create A Slow Function



In [2]:

    
def slow_function():
    total = 0.0
    
    for i, _ in enumerate(range(10000)):
        
        for j, _ in enumerate(range(1, 10000)):
            total += (i * j)

    return total

Test The Speed Of The Function



In [3]:

    
cProfile.run('slow_function()', sort='time')









    



         4 function calls in 13.291 seconds

   Ordered by: internal time

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1   13.291   13.291   13.291   13.291 <ipython-input-2-64fc1cd43878>:1(slow_function)
        1    0.000    0.000   13.291   13.291 {built-in method builtins.exec}
        1    0.000    0.000   13.291   13.291 <string>:1(<module>)
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}

How To Read cProfile's Output

ncalls: Number of calls to the function.
tottime: Total time.
percall: Time per call.
cumtime: Total time in function and sub-functions.
percall: Time to call.
:lineno(function): Name of the operation.

Alternative In Jupyter Notebook:



In [4]:

    
%%timeit

slow_function()









    



1 loop, best of 3: 12.9 s per loop