Python 101 – Lists, Tuples

Lists

A list in python is created by using square brackets, and seperating values using commas.

list = ['first', 'second', 'third', 'forth']

All of the values within the list can be shown by calling the entire list

print(list)
['first', 'second', 'third', 'forth']

You are able to access specific values within the list by specifying the index value

print(list[0])
first

To update a value within the list you need to specify the index value, similar when you read the value

list[0] = 'last'
print(list[0])
last

Finally, to delete a value within a list, you can do the following

del list[0]
print(list)
['second', 'third', 'forth']

Tuples

A tuple is similar to a list, where it is a collection of objects, however a tuple cannot be changed unlike lists. A tuple is created either with or without parenthesis.

tup1 = ('first', 'second', 'third')
tup2 = 'fourth',

Notice how ‘tup2’ has only one value, but it must contain a comma after the value.

Tuples are accessed the same way as lists

print(tup1[0])
first

As previously mentioned, tuples cannot be updated or modified, however you can join two tuples together.

tup3 = tup1 + tup2
print(tup3)
('first', 'second', 'third', 'fourth')

You cannot delete values within a tuple, but you can create a new tuple and exclude the values you no longer want. To remove an entire tuple, you can use del, similar to lists:

del tup3