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Python Functional Python The Lambda Lambada Reduce

Posted by pala
pala
15,913 Points

python map and reduce question

I can't use map and reduce function to pass the challenge, don't know how to do...

from operator import add
from functools import reduce

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

def product_sales(price):
    return price[0] * price[1]

total = reduce(map(products_sales, price), price for price in prices)  # question

1 Answer

Brendan Whiting
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.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,738 Points
Brendan Whiting
.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,738 Points

The two arguments you need to put into reduce are first the function you're using to reduce, and then the iterable you're reducing. The function is add and the iterable is what will be returned from map(product_sales, prices).

total = reduce(add, map(product_sales, prices))
pala
pala
15,913 Points

thank you! I got it!