Python Sets

Here’s an example of creating a set:

python

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

In this example, my_set is a set containing the numbers 1, 2, 3, 4, and 5.

Sets automatically eliminate duplicate elements, so if you try to add a duplicate value to a set, it will be ignored. For example:

python

my_set = {1, 2, 3, 3, 4, 4, 5}
print(my_set)

Output:

{1, 2, 3, 4, 5}

Sets support various operations such as union, intersection, difference, and symmetric difference. These operations can be performed using built-in methods or operators. Here are some common set operations:

• Union: set1 | set2 or set1.union(set2) returns a new set with all elements from both set1 and set2.
• Intersection: set1 & set2 or set1.intersection(set2) returns a new set with elements present in both set1 and set2.
• Difference: set1 - set2 or set1.difference(set2) returns a new set with elements from set1 that are not in set2.
• Symmetric Difference: set1 ^ set2 or set1.symmetric_difference(set2) returns a new set with elements that are in either set1 or set2, but not both.

Sets are also useful for checking membership and performing fast membership testing. You can use the in operator to check if an element is present in a set. For example:

python

my_set = {1, 2, 3, 4, 5}
print(3 in my_set)  # Output: True
print(6 in my_set)  # Output: False

Sets can be modified by adding or removing elements using methods such as add(), remove(), discard(), pop(), and clear(). For example:

python

my_set = {1, 2, 3}
my_set.add(4)        # Add a single element
my_set.update([5, 6])  # Add multiple elements
my_set.remove(3)     # Remove an element
my_set.discard(2)    # Remove an element if it exists, or do nothing if it doesn't
my_set.pop()         # Remove and return an arbitrary element
my_set.clear()       # Remove all elements from the set

Sets are particularly useful when you need to perform operations like finding unique elements, removing duplicates, or checking membership efficiently.