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Python Introducing Lists Using Lists Multidimensional Lists

Magnus Lindberg Christensen
Magnus Lindberg Christensen
2,231 Points
Posted by Magnus Lindberg Christensen
Magnus Lindberg Christensen
2,231 Points

Multidimensional Lists

Hey

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
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?