Example of Python Sets
Python3
var = {"Geeks", "for", "Geeks"}type(var) |
Output:
set
Time Complexity: O(1)
Auxiliary Space: O(1)
Type Casting with Python Set method
The Python set() method is used for type casting.
Python3
# typecasting list to setmyset = set(["a", "b", "c"])print(myset)# Adding element to the setmyset.add("d")print(myset) |
Output:
Python set is an unordered datatype, which means we cannot know in which order the elements of the set are stored.
{'c', 'b', 'a'}
{'d', 'c', 'b', 'a'}
Time Complexity: O(n)
Auxiliary Space: O(n)
Check unique and Immutable with Python Set
Python sets cannot have a duplicate value and once it is created we cannot change its value.
Python3
# Python program to demonstrate that# a set cannot have duplicate values # and we cannot change its items# a set cannot have duplicate valuesmyset = {"Geeks", "for", "Geeks"}print(myset)# values of a set cannot be changedmyset[1] = "Hello"print(myset) |
Output:
The first code explains that the set cannot have a duplicate value. Every item in it is a unique value.
The second code generates an error because we cannot assign or change a value once the set is created. We can only add or delete items in the set.
{'Geeks', 'for'}
TypeError: 'set' object does not support item assignment
Heterogeneous Element with Python Set
Python sets can store heterogeneous elements in it, i.e., a set can store a mixture of string, integer, boolean, etc datatypes.
Python3
# Python example demonstrate that a set# can store heterogeneous elementsmyset = {"Geeks", "for", 10, 52.7, True}print(myset) |
Output:
{True, 10, 'Geeks', 52.7, 'for'}
Time Complexity: O(n)
Auxiliary Space: O(n)
Sets in Python
A Set in Python programming is an unordered collection data type that is iterable, mutable and has no duplicate elements.
Set are represented by { } (values enclosed in curly braces)
The major advantage of using a set, as opposed to a list, is that it has a highly optimized method for checking whether a specific element is contained in the set. This is based on a data structure known as a hash table. Since sets are unordered, we cannot access items using indexes as we do in lists.