Checkpoint 9.1.1.
- True
- lists can have different data types.
- False
- lists can contain any combination of items, even other lists!
Q-2: True or False? A list can contain only integer items.
Section 9.1 A list is a sequence
Like a string, a list is a sequence of values. In a string, the values are characters; in a list, they can be any type. The values in list are called elements or sometimes items.
There are several ways to create a new list; the simplest is to enclose the elements in square brackets (“[” and “]”):
[10, 20, 30, 40]
['crunchy frog', 'ram bladder', 'lark vomit']
The first example is a list of four integers. The second is a list of three strings. The elements of a list don't have to be the same type. The following list contains a string, a float, an integer, and (lo!) another list:
['spam', 2.0, 5, [10, 20]]
A list within another list is nested.
A list that contains no elements is called an empty list; you can create one with empty brackets,
[].As you might expect, you can assign list values to variables:
Checkpoint 9.1.2.
- 1
- There is only one number in the list, but that is not the length.
- 3
- There are three strings in the list, but that is not the length.
- 4
- There are 4 items in this list (three strings and a number) making the length 4.
- 5
- The value of the number in this list is 5, but that is not the length.
Q-3: What is the length of the list [“Sue”,“Maria”,5,“Erica”]?
Checkpoint 9.1.3.
Q-4: A list within another list is said to be __________.
