findmax.py

#!/usr/bin/env python
#
# This python file contains script to find the maximum frequency carriers
#  and origin and destination airports
#
# Author - Prateek & Nishant
#
#
# After running it on 10^6 random samples the max are
# Top 20 carriers : ['WN', 'DL', 'AA', 'UA', 'US', 'NW', 'CO', 'MQ', 'HP', 'OO', 'TW', 'AS', 'XE', 'EV', 'OH', 'FL', 'DH', 'B6', 'YV', 'TZ'] 
# Top 20 origins : ['ORD', 'ATL', 'DFW', 'LAX', 'PHX', 'IAH', 'DEN', 'DTW', 'MSP', 'LAS', 'STL', 'EWR', 'SFO', 'CLT', 'BOS', 'PHL', 'LGA', 'CVG', 'MCO', 'SEA']
# Top 20 destination : ['ORD', 'ATL', 'DFW', 'LAX', 'PHX', 'IAH', 'DEN', 'DTW', 'MSP', 'LAS', 'STL', 'EWR', 'SFO', 'CLT', 'BOS', 'PHL', 'LGA', 'CVG', 'MCO', 'SEA']
#

import csv
import sys
import operator

if len(sys.argv) < 2:
    message = bcolors.BOLD + "Usage: python findmax.py <input file>" + bcolors.ENDC
    sys.exit(message)

# Take the input file
input_file = sys.argv[1]

# dictionaries
origin = {}
dest = {}
carrier = {}

inp = open(input_file,"rb")

first=0
# loop over file
for line in inp:
	
	#ignore first
	if first==0:
		first=1
		continue

	arr = line.split(",")

	car = arr[8]
	ori = arr[16]
	des = arr[17]

	if car in carrier:
		carrier[car]+=1
	else:
		carrier[car]=0

	if ori in origin:
		origin[ori]+=1
	else:
		origin[ori]=0

	if des in dest:
		dest[des]+=1
	else:
		dest[des]=0

# Sort the inputs
carrier = sorted(carrier.items(), key=operator.itemgetter(1),reverse=True)
dest = sorted(dest.items(), key=operator.itemgetter(1),reverse=True)
origin = sorted(origin.items(), key=operator.itemgetter(1),reverse=True)

# print maximums
print [x[0] for x  in (carrier[0:20])]
print [x[0] for x  in (origin[0:20])]
print [x[0] for x  in (dest[0:20])]