Python Set Difference

Python Set Difference Tutorial with Programs and Example 

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The Python set difference is similar to the difference between the two sets of the number of elements.

The difference() function returns a set that is the difference between two sets.

Example:

set A = {1, 2, 3, 4, 8}
set B = {1, 3, 8, 4, 6}

set A - set B = {2, 6}
set B - set A = {6}

Explanation: 
A - B is equal to the elements present in A but not in B
B - A is equal to the elements present in B but not in A

What is Python set difference?

Python set difference method is an operation that returns a set containing the difference between two sets.

The returned set comprises just those elements that exist in the first set, not in both.

Further, Python includes a set data structure for implementing sets.

In addition, it provides a variety of additional functions that facilitate common set operations such as union, intersection, difference, etc.

difference() Syntax

A.difference(B)

Here, A and B represent two sets.

difference() Parameter

The method difference() accepts a single argument:

  • B- a set whose elements are not contained in the final set.

difference() Return Value

The difference() method returns:

  • a set with elements unique to the first original sets.

Set difference() Python example

A = {'red', 'white', 'yellow', 'blue'}
B = {'blue', 'red', 'green'}

print(A.difference(B))

print(B.difference(A))

Output:

{'yellow', 'white'}
{'green'}

In the preceding example, we utilized the difference() method to compute the set differences between two sets A and B.

Here is how it works:

  • A.difference(B) – returns a set with elements unique to set A
  • B.difference(A) – returns a set with elements unique to set B

Set difference python Using Operator

Another way to determine the set difference in Python is by using an operator.

For example:

A = {'apple', 'orange', 'kiwi', 'atis'}
B = {'atis', 'grapes', 'lemon'}

print(A - B)

print(B - A)

Output:

{'orange', 'kiwi', 'apple'}
{'grapes', 'lemon'}

Here, we have used the – operator to compute the set difference of two sets A and B.

How do you print the difference between two sets in Python?

In this program, we will try to find out how to print the difference between two sets.

A = {2, 4, 6, 8, 10}
B = {4, 6, 8, 10, 12}

print(A.difference(B))
print(B.difference(A))

Output:

{2}
{12}

Conclusion

Python is well-known for its simple, English-like syntax.

Python offers us a vast number of built-in functions that allow us to do many major set operations.

  • A difference between two sets returns a new set that has elements from the first set that are not present in the second set.
  • Use the set difference() method or set difference operator (-) to find the difference between sets.

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