Python - Join Sets
Join Two Sets
There are several ways to join two or more sets in Python.
You can use the union() method that returns a new set containing all items from both sets, or the update() method that inserts all the items from one set into another:
Example
The union() method returns a new set with all items from both sets:
set1 = {"a", "b" , "c"}
set2 = {1, 2, 3}
set3 = set1.union(set2)
print(set3)
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Example
The update() method inserts the items in set2 into set1:
set1 = {"a", "b" , "c"}
set2 = {1, 2, 3}
set1.update(set2)
print(set1)
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Note: Both union() and update() will exclude any duplicate items.
Keep ONLY the Duplicates
The intersection_update() method will keep only the items that are present in both sets.
Example
Keep the items that exist in both set x, and set y:
x = {"apple", "banana", "cherry"}
y = {"google", "microsoft", "apple"}
x.intersection_update(y)
print(x)
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The intersection() method will return a new set, that only contains the items that are present in both sets.
Example
Return a set that contains the items that exist in both set x, and set y:
x = {"apple", "banana", "cherry"}
y = {"google", "microsoft", "apple"}
z = x.intersection(y)
print(z)
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Keep All, But NOT the Duplicates
The symmetric_difference_update() method will keep only the elements that are NOT present in both sets.
Example
Keep the items that are not present in both sets:
x = {"apple", "banana", "cherry"}
y = {"google", "microsoft", "apple"}
x.symmetric_difference_update(y)
print(x)
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The symmetric_difference() method will return a new set, that contains only the elements that are NOT present in both sets.
Example
Return a set that contains all items from both sets, except items that are present in both:
x = {"apple", "banana", "cherry"}
y = {"google", "microsoft", "apple"}
z = x.symmetric_difference(y)
print(z)
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Note: The values True and 1 are considered the same value in sets, and are treated as duplicates:
Example
True and 1 is considered the same value:
x = {"apple", "banana", "cherry", True}
y = {"google", 1, "apple", 2}
z = x.symmetric_difference(y)
print(z)
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