Testing, profiling and optimization

Question 1

pytest of factorial(order)

Answer 1

import pytest
from script import factorial

def test_factorial():
    assert factorial(3) == 6

if __name__ == “__main__”:
pytest.main(“thisfile.py”)

Question 2

doctest of factorial(order)

Answer 2

def factorial(order):
    """
>>> factorial(3)
6
    """

Question 3

profile factorial(6)

Answer 3

import cProfile
import pstats

from script import factorial

cProfile.run(“factorial(6)”, “factorial”)
pstats.Stats(“factorial”).print_stats()

Question 4

time factorial(6)

Answer 4

from timeit import timeit

timeit(“factorial(6)”, “from script import factorial”, number=100000)

Question 5

time a block of code

Answer 5

from time import time

timer = time()
# Do something
timer = time() - timer
print timer

Question 6

optimization in python

Answer 6

Local name space > Global name space
if-elif-else > try-except-default
Few function arguments > Many function arguments
xrange > range
Python native initialisation > Numpy initialisation
Numpy iteration > Python native iteration

Question 7

weave

Answer 7

from scipy import weave

weave.inline(“””//code”””, [‘var1’, ‘var2’], type_converters = weave.converters.blitz, headers = [’’])

NB! Primitive types are copied (I think)