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What are Advanced Sets in python with examples.

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In this lecture, we will learn about the various methods for sets that you may not have seen yet. We’ll go over the basic ones you already know and then dive a little deeper.

s = set()

add add elements to a set. Remember, a set won’t duplicate elements; it will only present them once (that’s why it’s called a set!)

s.add(1)
s.add(2)
s
{1, 2}

clear removes all elements from the set

s.clear()
s
set()

copy returns a copy of the set. Note it is a copy, so changes to the original don’t effect the copy.

s = {1,2,3}
sc = s.copy()
sc
{1, 2, 3}
S
Output-
{1, 2, 3}
s.add(4)
s
{1, 2, 3, 4}
Sc
Output-
{1, 2, 3}

difference difference returns the difference of two or more sets. The syntax is:

set1.difference(set2)
For example:
s.difference(sc)
{4}

difference_update difference_update syntax is:

set1.difference_update(set2)

the method returns set1 after removing elements found in set2

s1 = {1,2,3}
s2 = {1,4,5}
s1.difference_update(s2)
s1
{2, 3}

discard Removes an element from a set if it is a member. If the element is not a member, do nothing.

S
Output-
{1, 2, 3, 4}
s.discard(2)
s
output-
{1, 3, 4}

intersection and intersection_update Returns the intersection of two or more sets as a new set.(i.e. elements that are common to all of the sets.)

s1 = {1,2,3}
s2 = {1,2,4}
s1.intersection(s2)
{1, 2}
s1
output-
{1, 2, 3}

intersection_update will update a set with the intersection of itself and another.

s1.intersection_update(s2)
s1
output-
{1, 2}

isdisjoint This method will return True if two sets have a null intersection.

s1 = {1,2}
s2 = {1,2,4}
s3 = {5}
s1.isdisjoint(s2)
output-
False

s1.isdisjoint(s3)
output-
True

issubset This method reports whether another set contains this set.

s1
{1, 2}

s2
{1, 2, 4}

s1.issubset(s2)
True

issuperset This method will report whether this set contains another set.

s2.issuperset(s1)
True
s1.issuperset(s2)
False

symmetricdifference and symmetricupdate Return the symmetric difference of two sets as a new set.(i.e. all elements that are in exactly one of the sets.)

s1
output-
{1, 2}
s2
output-
{1, 2, 4}
s1.symmetric_difference(s2)
output-
{4}

union Returns the union of two sets (i.e. all elements that are in either set.)

s1.union(s2)
output-
{1, 2, 4}

update Update a set with the union of itself and others.

s1.update(s2)
s1
output-
{1, 2, 4}

Great! You should now have a complete awareness of all the methods available to you for a set object type. This data structure is extremely useful and is underutilized by beginners, so try to keep it in mind!