tip_cal_exception.py

import tip_calculator_as_functions
import sys


def calculate_rate(base, percentage):
    return base * percentage
 
def calculate_meal_costs(meal_base, tax_rate, tip_rate):
    """
    Calculates dollar amounts for tax, tip, and total meal cost
    """
    tax_value = calculate_rate(meal_base, tax_rate)
    meal_with_tax = tax_value + meal_base
    tip_value = calculate_rate(meal_with_tax, tip_rate)
    total = meal_with_tax + tip_value
    
    meal_info = dict(meal_base=meal_base,
                    tax_rate=tax_rate,
                    tip_rate=tip_rate,
                    tax_value=tax_value,
                    total = total)
    return meal_info

	


def main ():
	try:
		meal = float(sys.argv[1])
		tip  = float(sys.argv[2])
		tax  = float(sys.argv[3])
		meal_info = calculate_meal_costs(meal,tax,tip)	
		
	except ValueError:
		print("Sorry, you must supply numbers for all input parameters to this script. Try again.")
		meal       = float(raw_input("Enter the cost of your meal before taxes: "))
		tax        = float(raw_input("Enter the state tax: "))
		tip        = float(raw_input("Enter the tip amount: "))
		meal_info = calculate_meal_costs(meal,tax,tip)
	
	print "The base cost of your meal was ${0:.2f}.".format(meal_info['meal_base'])
	print "You need to pay ${0:.2f} for tax.".format(meal_info['tax_rate'])
	print "Tipping at a rate of {0}%, you should leave ${1:.2f} for a tip.".format(
	                                                        int(100*meal_info['tip_rate']), meal_info['tax_value'])
	print "The grand total of your meal is ${0:.2f}.".format(meal_info['total'])


if __name__ == '__main__':
	main()