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Python Functional Python The Lambda Lambada Reduce

Posted by Rutendo Chaurura
Rutendo Chaurura
6,809 Points

This code i not passing

We have a bunch of prices and sales numbers and we need to find out our total earnings.

Let's start by writing a function named product_sales that takes a single two-member tuple made up of a price and a number of units sold. product_sales should return the product of the price and the number of units.

prices.py 
prices = [
    (6.99, 5),
    (2.94, 15),
    (156.99, 2),
    (99.99, 4),
    (1.82, 102)
]

def product_sales(price, units):
    return price * units

2 Answers

Steven Parker
Steven Parker
221,451 Points
Steven Parker
Steven Parker
221,451 Points

This function takes two individual arguments, but the instructions ask for a function " that takes a single two-member tuple"

So your declaration might look something like:

def product_sales(one_tuple):

And of course, the body would need to be adapted accordingly.

busongomwembe
busongomwembe
30,682 Points

We have a bunch of prices and sales numbers and we need to find out our total earnings.

Let's start by writing a function named product_sales that takes a single two-member tuple made up of a price and a number of units sold. product_sales should return the product of the price and the number of units.

prices = [ (6.99, 5), (2.94, 15), (156.99, 2), (99.99, 4), (1.82, 102) ] def product_sale(single_two): price,units=single_two return price* units print(reduce(product_sale,prices))

NB why not working too

Steven Parker
Steven Parker
221,451 Points
Steven Parker
Steven Parker
221,451 Points

Two issues here:

  • the instructions ask for a function named product_sales (plural) not "product_sale" (singular)
  • the "print" statement is not something asked for by the instructions and will confuse the evaluator
Learn QA
Learn QA
6,011 Points
Learn QA
Learn QA
6,011 Points

def product_sales(one_tuple): product_sales = 21.0 return product_sales

this code passed but not sure how

Steven Parker
Steven Parker
221,451 Points
Steven Parker
Steven Parker
221,451 Points

Looks like you tricked the challenge by guessing the result for the values it tested with.
But a valid solution would use the argument and calculate) the result.