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# Python Set Difference() Method Example Tutorial

Python set difference() is an inbuilt function that helps us to find the difference between two given sets. It works like a math intersection (A∩B). Means, if A and B are two sets, then their difference will be:

A-B = A-(A∩B)

B-A = B-(A∩B)

The difference() method returns the set difference of two sets. If A and B are two sets. The set difference of A and B is a set of elements that exist only in set A but not in B.

## Python Set Difference()

Python sets, and four great operations they provide:

1. Intersection: Elements two sets have in common.
2. Union: All the elements from both sets.
3. Difference: Elements present on one set, but not on the other.
4. Symmetric Difference: Elements from both sets, that are not present on the other.

Consider the following image for better understanding.

Here, A contains {a,b,c,d,e} and B contains {a,e,f,g} . So A-B={b,c,d} and B-A={f,g} .

#### Syntax

`First_Set.difference(Second_Set)`

The above syntax will help us to find the difference between First_Set-Second_Set.

So, If we want to find A-B, the syntax will be the following.

`A.difference(B)`

#### Return Value

The difference() function returns the difference of two given set without changing the original sets. This means it returns a new set.

#### Programming Example

See the following code example.

```# app.py

# Declaring two sets
A = {'a', 'b', 'c', 'd', 'e'}
B = {'a', 'e', 'f', 'g'}

# Now we will apply difference() to find

# A-B
print("Difference between A-B is: ", A.difference(B))
# B-A
print("Difference between B-A is: ", B.difference(A))
```

#### Output

```Difference between A-B is:  {'c', 'b', 'd'}
Difference between B-A is:  {'g', 'f'}
```

Here in this example, we have declared two sets A and B, and then we have used the difference() method to find the difference between the two sets.

## Using minus (-) operator

See the following code.

```# app.py

# Declaring two sets
A = {'a', 'b', 'c', 'd', 'e'}
B = {'a', 'e', 'f', 'g'}

# Now we will apply the minus operator to find

# A-B
print("Difference between A-B is: ", A-B)
# B-A
print("Difference between B-A is: ", B-A)
```

#### Output

```Difference between A-B is:  {'d', 'c', 'b'}
Difference between B-A is:  {'g', 'f'}
```

Here in this example, we have declared two sets A and B, and then we have used minus operator (-) to find the difference between the two sets.

In both cases, the original sets are not changed; it remains unchanged.

The difference between the two sets in Python is equal to the difference between the number of elements in two sets.

Finally, Python Set Difference() Method Example Tutorial is over.