list
less than a minute
A list is a data structure for storing a series of related pieces of information.
Defining a list
You can define a list using square brackets, with the elements separated by commas, like this:
squares = [0, 1, 4, 9, 16, 25, 36]
vowels = ["a", "e", "i", "o", "u"]
Selecting elements
You can pick an element from the list like this: squares[0]
. Note that counting begins at zero.
Think of the number as “how far from the beginning” the element in the list is.
So vowels[0]
is the element at the start of the list, and vowels[3]
is three elements further down the list. So the string "u"
in that list would be vowels[4]
.
Adding elements
You can add elements to the end of a list with the append()
function.
squares.append(49)
print(squares[7])
# Output: 49
Removing elements
You can remove elements from a list with remove()
and pop()
.
friends = ["Nhi", "David", "Hari", "Zahra"]
friends.remove("David")
print(friends)
# Output: ["Nhi, "Hari", "Zahra"]
If there are multiple elements in the list with the same value, remove()
will remove just the first one.
friends = ["Nhi", "David", "Hari", "Zahra"]
exBestie = friends.pop(0)
print(friends)
# Output: ["David", "Hari", "Zahra"]
print(exBestie)
# Output: "Nhi"