10.3. List Length¶
As with strings, the function
len returns the length of a list (the number
of items in the list). However, since lists can have items which are themselves lists, it important to note
len only returns the top-most length. In other words, sublists are considered to be a single
item when counting the length of the list.
Check your understanding
- len returns the actual number of items in the list, not the maximum index value.
- Yes, there are 5 items in this list.
list-3-1: What is printed by the following statements?
alist = [3, 67, "cat", 3.14, False] print(len(alist))
- Yes, there are 7 items in this list even though two of them happen to also be lists.
- len returns the number of top level items in the list. It does not count items in sublists.
list-3-2: What is printed by the following statements?
alist = [3, 67, "cat", [56, 57, "dog"], [ ], 3.14, False] print(len(alist))