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Python Introducing Lists Using Lists Multidimensional Lists

Posted by Benyamin Kohanchi
Benyamin Kohanchi
Courses Plus Student 2,342 Points

what does "week" in sum(week) mean in Craig's code?

When Craig writes out his code to show the amount of expenses he incurred for 3 weeks respectively, what is the word week in sum(week) in the "for" block doing? How is it related to the "week" in "for week in travel_expenses"?

Here's the code:

travel_expenses = [
    [5.00, 2.75, 22.00, 0.00, 0.00],
    [24.75, 5.50, 15.00, 22.00, 8.00],
    [2.75, 5.50, 0.00, 29.00, 5.00],
]

print("Travel Expenses:") 
week_number = 1 
for week in travel_expenses:
    print("* Week #{}: ${}".format(week_number, sum(week)))
    week_number += 1

Thanks in advance 😁

1 Answer

Josh Keenan
Josh Keenan
20,315 Points
Josh Keenan
Josh Keenan
20,315 Points

Week is referring to the item currently being used by your for loop.

for week in travel_expenses:

In this context week will be one of the arrays of numbers in the variable travel_expenses. You can use any name* for whatever it is you wish to go over with your for loop.

*except for reserved words like print or while.

Benyamin Kohanchi
Benyamin Kohanchi
Courses Plus Student 2,342 Points

great thanks!