Python | set() Function

set() method is used to convert any of the iterable to a sequence of iterable elements with distinct elements, commonly called Set. In Python, the set() function is a built-in constructor that is used to initialize a set or create an empty. In this article, we will see about set() in Python and how we can convert an iterable to a sequence with unique elements in Python.

Python set() Method Syntax

Syntax: set(iterable)
Parameters : Any iterable sequence like list, tuple or dictionary.
Returns : An empty set if no element is passed. Non-repeating element iterable modified as passed as argument. 

What is Python set() Function?

Set, a term in mathematics for a sequence consisting of distinct languages is also extended in its language by Python and can easily be made using set(). set() method is used to convert an iterable to a sequence with unique elements in Python, commonly called Set. It is a built-in constructor function that is used to create an empty set or initialize a set with elements.

Properties of Python set() Method

• No parameters are passed to create the empty set
• The dictionary can also be created using a set, but only keys remain after conversion, and values are lost.

set() Function in Python Examples

Below are the ways by which we can use set() in Python:

• Creating an Empty Set
• Using set() with List
• Using set() with Tuples
• Creating set with Range
• Converting Dictionary into a Set

Creating a Set by using set() Function

In this example, we are creating a Set using set() function.

Python3

# we are creating an
#empty set by using set()

s = set()
print("Type of s is ",type(s))

Output

Type of s is  <class 'set'>

set() Function with List

In this example, we are using set() with List. Here, we will convert an iterable to a sequence with unique elements in Python.

Python3

# working of set() on list
# initializing list
lis1 = [ 3, 4, 1, 4, 5 ]

# Printing iterables before conversion
print("The list before conversion is : " + str(lis1))

# Iterables after conversion are
# notice distinct and elements
print("The list after conversion is : " + str(set(lis1)))

Output

The list before conversion is : [3, 4, 1, 4, 5]
The list after conversion is : {1, 3, 4, 5}

set() Function with Tuple

In this example, we are using set() function with tuple.

Python3

# working of set() on tuple
# initializing tuple
tup1 = (3, 4, 1, 4, 5)

# Printing iterables before conversion
print("The tuple before conversion is : " + str(tup1))

# Iterables after conversion are
# notice distinct and elements
print("The tuple after conversion is : " + str(set(tup1)))

Output

The tuple before conversion is : (3, 4, 1, 4, 5)
The tuple after conversion is : {1, 3, 4, 5}

set() Function with Range

In this example, we are using set() function with range function. Here, we will convert an iterable to a sequence with unique elements in Python.

Python3

# working of set() on range

# initializing range
r = range(5)

r=set(r)
# Iterables after conversion are
# notice distinct and elements
print("The Range after conversion is : " + str(r))

Output

The Range after conversion is : {0, 1, 2, 3, 4}

Demonstration of set() Method with Dictionary

In this example, we are seeing the demonstration of set() with Dictionary and it’s working.  

Python3

# Python3 code to demonstrate the
# working of set() on dictionary

# initializing list
dic1 = { 4 : 'geeks', 1 : 'for', 3 : 'geeks' }

# Printing dictionary before conversion
# internally sorted
print("Dictionary before conversion is : " + str(dic1))

# Dictionary after conversion are
# notice lost keys
print("Dictionary after conversion is : " + str(set(dic1)))

Output

Dictionary before conversion is : {4: 'geeks', 1: 'for', 3: 'geeks'}
Dictionary after conversion is : {1, 3, 4}