CODEWITHSUNDEEP
python
JuanB457
JuanB457

Reputation: 107

Python float numbers and correct use

I am typing a program for my class, the problem is worded very odd, but I have put in my code for the problem, am I declaring the numbers as float correctly? Simple question but I'm keeping my mind open to other ways of doing things. 

print " This program will calculate the unit price (price per oz) of store items,"
print " you will input the weight in lbs and oz, the name and cost." 
item_name = (input("Please enter the name of the item. ")) 
item_lb_price = float(input("Please enter the price per pound of your item ")) 
item_lbs = float(input("please enter the pounds of your item. "))
item_oz = float(input("plese enter the ounces of your item. "))
unit_price = item_lb_price / 16
total_price = item_lb_price * (item_lbs + item_oz / 16) 
print "the total price per oz is", unit_price 
print "the total price for", item_name, "is a total of", total_price

Upvotes: 2

Views: 1448

Answers (3)

Kyle Kelley
Kyle Kelley

Reputation: 14144

Your floats are fine.

You need to use raw_input though to get a string back.

input("Enter a number") is equivalent to eval(raw_input("Enter a number")). Currently the code tries to evaluate the input as code (run as a python expression).

15:10:21 ~$ python so18967752.py
 This program will calculate the unit price (price per oz) of store items,
 you will input the weight in lbs and oz, the name and cost.
Please enter the name of the item. Apple
Traceback (most recent call last):
  File "so18967752.py", line 6, in <module>
    item_name = (input("Please enter the name of the item. "))
  File "<string>", line 1, in <module>
NameError: name 'Apple' is not defined

Other comments:

  1. For your multiline banner at the top, declare the string as a multiline string and print that.
  2. Check to make sure the ranges make sense for the inputs (validate). Of course, if this is for a class you may not have reached this point (Seen if/else?)
  3. Be explicit with your constants to make them floats to make sure it doesn't default to integer division

Slightly cleaned up form:

banner = '''
This program will calculate the unit price (price per oz) of store items.
You will input the weight in lbs and oz, the name and cost.
'''

print banner

item_name = raw_input("Please enter the name of the item. ")

item_lb_price = float(raw_input("Please enter the price per pound of your item."))
item_lbs = float(raw_input("Please enter the pounds of your item."))
item_oz = float(raw_input("plese enter the ounces of your item."))

unit_price = item_lb_price / 16.0
total_price = item_lb_price * (item_lbs + (item_oz / 16.0))

print "The total price per oz is", unit_price
print "The total price for", item_name, "is a total of", total_price

Upvotes: 1

Shani
Shani

Reputation: 418

if it is python 2 you should be using raw_input instead of input. if it is python 3 you should be enclosing the values you want to print in parentheses.

yes you are using the float function correctly but are not verifying that the input is correct. it is liable and even likely to throw errors.

besides the program is not correct for python 2 because of the input() and not correct for python 3 because of the use of the print statement.

And you should devide by a float: 16.0 instead 16.

Upvotes: 1

Ronny Andersson
Ronny Andersson

Reputation: 1687

Division in python is per default using integers, so if you want a floating point result you should divide by 16.0

unit_price = item_lb_price / 16.0

Upvotes: 0

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