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Confused on how to make Python code more efficient

Hi Guys,

I'm new to Python Programming. I'm used to Ruby and how you don't really have to have return statements and such for your functions. Learning Python has been a real struggle for me. I'm trying to create a simple fuel calculation program below and feel i had to type so much code in order to get input from a user and convert that string input back to either a float or int. Is there anyway I can make my code more efficient? Are there any better practices I can follow? I don't seem to understand why self always have to be called because in Ruby you never have to worry about "self"

#!/usr/bin/python

class TripCost:
	def __init__(self, miles_per_gallon, distance, price_per_gallon):
		self.miles_per_gallon = miles_per_gallon
		self.distance = distance
		self.price_per_gallon = price_per_gallon
	#self always has to explicityly called when using class level functions
	def Mileageprice_per_gallon(self):
		return (self.price_per_gallon * self.distance)
	def Roundtrip(self):
		return(self.distance * 2)

#Creating a new object called trip with a car that has 22 mpg 13.6 mile drive and 3.27 for gas
trip1 = TripCost(22, 13.5, 3.27)
mpg =trip1.Mileageprice_per_gallon()
print "The cost of the price per gallon and distance will be : " 
print mpg
roundTrip = trip1.Roundtrip()
print "The round trip will be"
print roundTrip
x_mpg = raw_input('How many miles per gallon does your vehicle give you?')
print 'Your vehicle gives you ' + x_mpg
x_distance = raw_input('How Far is your one way commute? ')
print 'Your one way commute is ' + x_distance
x_price_per_gallon = raw_input('What is the cost of fuel per gallon?')
print 'The cost of fuel is ' + x_price_per_gallon
#Convert all string input to integers
i_mpg = int(x_mpg)
print i_mpg
i_distance = float(x_distance)
print i_distance
mult = (i_distance * i_mpg)
print mult
i_price_per_gallon = float(x_price_per_gallon)
print i_price_per_gallon



trip2 = TripCost(i_mpg, i_distance, i_price_per_gallon)
mpg2 = trip2.Mileageprice_per_gallon()
print mpg2

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aikimark

I would refactor this into a function that has multiple parameters. The user supplies the necessary parameter values when they invoke the code.

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gelonida

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pepr

I do not know Ruby (a bit only). It could be nice if you show the Ruby equivalent of the code here. Then we can compare and discuss the differences better.

Now, some basic Python things. (I understand how beginners in some language feel even though they may be quite experienced in another one, no offence.)

In Python 2, print is a command (the print being a keyword). The list of arguments is comma separated, and the list is separated from the keyword by space. The print command converts each argument to the string representation, adds space for separation of arguments, and appends \n if you do not suppress it. This way, you can also write:

print "The cost of the price per gallon and distance will be :", mpg

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In Python 3, print is a built-in function. Because of that, you need to use parentheses when called. Otherwise, the behaviour resembles the Python 2 print command. When using the transitional Python 2.7, you can tell explicitly that you prefer the new form from Python 3.

The return is the command in both Pythons. This way, you need not use the parentheses -- they are parsed as belonging to the following expression, not to the return.