File for testing an algorithm for finding all potential pairs of numbers

test_pairs.py

#! /usr/bin/python

from time import time
from collections import Counter
from random import randint

#########################################
# Test functions. Used for testing
########################################
VALUES = (1, 100000)

def timer(func):
    def wrapper(data_one, data_two):
        n = len(data_one)
        t1 = time()
        ret = func(data_one, data_two)
        t2 = time()
        print "it took {} seconds to run with {} values".format(t2 - t1, n)
        return ret
    return wrapper

def test(n):
    main_data = [randint(*VALUES) for x in xrange(n)]
    sec_data = [randint(*VALUES) for x in xrange(n)]
    result = count_results(main_data, sec_data)

    print "result is ---> {}".format(result)

############################################
# Start Algorithm block
############################################

# Comment out decorator to remove timing
# testing.
@timer
def count_results(data_one, data_two):
    data_counter = generate_counters(data_two)
    result = 0

    for x in data_one:
        value_one = x + 2
        value_two = x - 2
        
        result += data_counter[value_one] + data_counter[value_two]

    return result

def generate_counters(data):
    result = Counter()

    for x in data:
        result[x] += 1

    return result

#############################################
# End Algorithm block
############################################

if __name__=="__main__":

    for x in [10, 100, 1000, 5000, 10000, 100000, 1000000, 10000000]:
        test(x)