Lists
Execute the commands from a Python Shell. Don’t type the comments.
List videos
Python Tutorial for Beginners 4: Lists, Tuples, and Sets
Index values
IndexErrorList slicing
[start:stop].append().insert().extend().pop().reverse().sort()sorted()min(),max(), andsum().index()inoperatorLoop through a list
enumerate().join().split()Tuples and Sets (Optional)
Python Tutorial: Slicing Lists and Strings (optional)
Creating a list
Below are some different ways you can create (initialize) a list.
>>> empty_list = []
>>> empty_list
[]
>>> another_empty_list = list()
>>> another_empty_list
[]
>>> odd_nums = [1, 3, 5, 7, 9]
>>> odd_nums
[1, 3, 5, 7, 9]
>>> my_friends = ["Jim", "Joe", "Sally"]
>>> my_friends
['Jim', 'Joe', 'Sally']
>>> vowels = ['a', 'e', 'i', 'o', 'u']
>>> vowels
['a', 'e', 'i', 'o', 'u']
>>> vowels = list("aeiou")
>>> vowels
['a', 'e', 'i', 'o', 'u']
>>> letters = list("hello")
>>> letters
['h', 'e', 'l', 'l', 'o']
>>> friends = "Jim Sally Joe".split(" ")
>>> friends
['Jim', 'Sally', 'Joe']
>>> friends = "Jim, Sally, Joe".split(", ")
>>> friends
['Jim', 'Sally', 'Joe']
Accessing list elements
>>> marks = [6, 2, 8, 5, 0, 4, 1] # Initalizing a list
>>> marks[0] # Access single element by index
6
>>> marks[3]
5
Slicing a list
>>> marks = [6, 2, 8, 5, 0, 4, 1]
>>> marks[3:5] # Slice list from index 3 up to (not including) 5
[5, 0]
>>> marks[:5] # Slice list from beginning up to (not including) 5
[6, 2, 8, 5, 0]
>>> marks[3:] # Slice list from 3 to the end
[5, 0, 4, 1]
>>> marks[:-1] # Slice list from beginning to (not including) the last element
[6, 2, 8, 5, 0, 4]
>>> marks[:] # Slice from beginning to the end (copy whole list)
[6, 2, 8, 5, 0, 4, 1]
>>> marks[::2] # Slice from beginning to the end stepping by 2
[6, 8, 0, 1]
>>> marks[::-1] # Slice from beginning to the end backwards
[1, 4, 0, 5, 8, 2, 6]
Appending elements to a list
>>> friends = ['Jim', 'Sally', 'Lucy']
>>> friends.append("ABC")
>>> friends
['Jim', 'Sally', 'Lucy', 'ABC']
>>> friends.append("Bob")
>>> friends
['Jim', 'Sally', 'Lucy', 'ABC', 'Bob']
Reassign element at list index
>>> friends = ['Jim', 'Sally', 'Lucy', 'ABC', 'Bob']
>>> friends[2] = "Abigail"
>>> friends
['Jim', 'Sally', 'Abigail', 'ABC', 'Bob']
Remove list element using .remove
>>> friends = ['Jim', 'Sally', 'Lucy', 'ABC', 'Bob']
>>> friends.remove("Lucy")
>>> friends
['Jim', 'Sally', 'ABC', 'Bob']
Remove list element at index using del
>>> friends = ['Jim', 'Sally', 'ABC', 'Bob']
>>> del friends[2]
>>> friends
['Jim', 'Sally', 'Bob']
Error
Under construction!