Python Set difference_update() Method
The difference_update() method removes all elements from the set that are also found in other specified sets or iterables. It modifes the original set in place.
Syntax
set1.difference_update(set2, set3, ..., setN)Parameters
set2, set3, ..., setN: One or more sets or iterables whose elements will be removed from the original set.
Return Value
Returns None. It modifies the original set in place.
Examples
Example 1: Difference update of two sets
a = {1, 2, 3, 4, 5}
b = {4, 5, 6}
a.difference_update(b)
print(a) # Outpt: {1, 2, 3}Example 2: Difference update of multiple sets
You can pass multiple sets, separated by commas, as arguments to the difference_update() method.
a = {1, 2, 3, 4, 5, 6, 7, 8}
b = {1, 2, 3}
c = {4, 5, 6}
a.difference_update(b, c)
print(a) # Outpt: {7, 8}Example 3: Difference update with different iterable types
The difference_update() method also accepts iterables of various types, such as lists or tuples, as its arguments.
a = {1, 2, 3, 4, 5, 6, 7, 8}
b = [1, 2, 3] # a list
c = (4, 5, 6) # a tuple
a.difference_update(b, c)
print(a) # Output: {7, 8}The -= Operator
The -= is a shorthand for performing a set difference update.
For example:
a = {1, 2, 3, 4, 5}
b = {4, 5}
a -= b
print(a) # Output: {1, 2, 3}The -= operator only works with sets and doesn’t support other iterables like lists or tuples.
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