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Python Introducing Lists Using Lists Multidimensional Lists

Magnus Lindberg Christensen
Magnus Lindberg Christensen
2,231 Points

Multidimensional Lists


Why is it, that we can write

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

and the computer then knows what exact week it is, since a completely new variable was made?? I cannot see any relation between the two

2 Answers

Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Hi Magnus, I hope I understand your question correctly.

The list travel_expenses contains three list items. That's why it is a multidimensional list. So when you use a for loop it will go over the first, second and third list inside travel_expenses. Since you created the variable week_number and assigned 1 to this variable, after every loop, you increment the week_number by one and print its value to the screen.

The relationship is: You have 3 lists that will take the for loop three times to go over it and you print and increment week_number accordingly. Plus every time you print the sum of the list that the for loop is looking at. One at a time.

Does this answers your question?