"""Efficiency and testing

"python debugger"

built-in to python

Allows step-by-step execution of the script

Allows flow contorl (can execute at any line or function)

Allows inspection of variables

one of many debuggers; some IDEs show visual execution

"""

"""lesson 1; pdb debugging """

import pdb

# pdb.set_trace() type h to see commands

values = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

mysum = 0

# for val in values:

# mysum = 0 # inside the loop error

# mysum += val

# print mysum

# pdb.set_trace() you can see the values in the loop. Neat!

def doubleval(argsum, val):

argsum = 0

newval = argsum + val

return newval

for val in values:

mysum = doubleval(mysum,val)

print mysum

"""lesson 2: logging """

import logging

logging.basicConfig(level=logging.INFO)

logging.debug('this message will be ignored') # will not print this

logging.info('this should be logged') # will print this

logging.warning('And this, too') # will not print this

"""lesson 3: Benchmarking: the Timeit Module"""

import timeit

print 'by index: ', timeit.timeit(stmt="mydict['c']", setup="mydict = {'a': 5, 'b': 6, 'c': 7}", number=1000000)

print 'by get: ', timeit.timeit(stmt="mydict.get('c')", setup="mydict ={'a': 5, 'b': 6, 'c': 7} ", number=1000000)

def testme(this_dict,key):

return this_dict[key]

print timeit.timeit("testme(mydict,key)", setup= "from __main__ import testme; mydict ={'a':1,'b':2,'c':3}; key='c'", number=1000000)

"""lesson 4: unittesting pytest module """

##################################

# in a file called myprogram.py #

##################################

import sys

def doubleit(x):

if not isinstance(x, (int,float))

var = x*2

return var

if __name__ == '__main__':

input_val = sys.argv[1]

double_val = doubleit(input_val)

print 'the value of {0} is {1}'.format(input_val, double_val)

######################################

# in a file called test_myprogram.py #

######################################

import myprogram

import pytest

def test_doubleit():

assert myprogram.doubleit(10) == 20

def test_doubleit_tyoe()

with pytest.raises(TypeError):

myprogram.doubleit('hello')