Makerspace

You can use lists to store multiple items in a single variable. Use square brackets to create a list. Here is a list with 4 elements:

groceries = ['eggs', 'milk', 'bread', 'coffee']
print(groceries)

Output:

['eggs', 'milk', 'bread', 'coffee']

You access items in the list using an index. The first item has index [0], the second has index [1], etc. This lets you print individual items:

print(groceries[2])

Output:

bread

It also lets you change individual items:

groceries[3] = 'decaf coffee'
print(groceries)

Output:

['eggs', 'milk', 'bread', 'decaf coffee']

You can add an item to the end of the list using append():

groceries.append('flour')
print(groceries)

Output:

['eggs', 'milk', 'bread', 'decaf coffee', 'flour']

You can delete an item using del:

del groceries[1]
print(groceries)

Output:

['eggs', 'bread', 'decaf coffee', 'flour']

A list can contain numbers, strings, or even a mix of both. Two or more lists can be combined using the + operator:

lottery_numbers = [4, 8, 15, 16, 23, 42]
big_list = groceries + lottery_numbers
print(big_list)

Output:

['eggs', 'bread', 'decaf coffee', 'flour', 4, 8, 15, 16, 23, 42]

Exercises

1. Create a list called fruits with the following elements: ‘apple’, ‘banana’, ‘orange’

   • Add ‘grape’ to the end of the list

     Hint: use the append() function

   • Change ‘banana’ to ‘pear’

   • Print the final list

2. Create a list of four consecutive numbers

   • Add the first and last elements of the list
   • Add the middle two elements of the list
   • Are the two sums the same or different?

3. Make a list of your favorite games and assign it to a variable named games. Make a list of your favorite foods and assign it to a variable named foods. Now combine these lists into a new list named favorites.

   • Now remove the third element of favorites, and print the new favorites list
   • Did removing the element from favorites affect either games or foods?