How To Create A Set In Python

This tutorial will discuss how to create a set in Python. Sets are a collection of unique elements, which are unordered, mutable, and do not support indexing or slicing.

In Python, the set data structure is used to store sets. It’s an efficient way to handle large data sets and perform operations like union, intersection, and differences between sets.

1. Creating an Empty Set

To create an empty set, you need to use the set() function. Using curly brackets {} will create an empty dictionary instead of an empty set.

1
empty_set = set()

2. Creating a Set with Values

To create a set with initial values, simply put the values inside curly brackets {} separated by commas.

1
values_set = {1, 2, 3, 4, 5}

3. Creating a Set from a List or Tuple

In case you have a list or tuple and want to create a set from its unique elements, you can use the set() function.

1
2
my_list = [1, 2, 3, 4, 5, 5, 4, 3, 2, 1]
my_set = set(my_list)

The same method applies for tuples:

1
2
my_tuple = (1, 2, 3, 4, 5, 5, 4, 3, 2, 1)
my_set = set(my_tuple)

4. Set Comprehensions

Just like list comprehensions, you can use set comprehensions to create sets. This method is usually more efficient and provides more concise syntax.

1
squared_set = {x**2 for x in range(1, 6)}

In this example, the squared_set will be a set containing the squares of numbers from 1 to 5.

Full Code

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
# Creating an empty set
empty_set = set()
 
# Creating a set with values
values_set = {1, 2, 3, 4, 5}
print(values_set)
 
# Creating a set from a list
my_list = [1, 2, 3, 4, 5, 5, 4, 3, 2, 1]
my_set = set(my_list)
print(my_set)
 
# Creating a set from a tuple
my_tuple = (1, 2, 3, 4, 5, 5, 4, 3, 2, 1)
my_set = set(my_tuple)
print(my_set)
 
# Set comprehensions
squared_set = {x**2 for x in range(1, 6)}
print(squared_set)

Output

{1, 2, 3, 4, 5}
{1, 2, 3, 4, 5}
{1, 2, 3, 4, 5}
{1, 4, 9, 16, 25}

Conclusion

Now, you should be able to create sets in Python using different methods. Sets are a powerful data structure that can simplify many tasks requiring the manipulation and analysis of large amounts of data.

With sets, you can easily perform operations like union, intersection, or difference between data sets, making them a valuable tool for any Python programmer.