How to find the Python intersection of two lists? Given two lists:
a = [1, 2, 3, 4, 5] b = [1, 3, 5, 6]
You want to find their intersection, meaning the elements present in both lists. For example:
Actual output: [1, 3, 5, 6] (incorrect for list intersection) Expected output: [1, 3, 5]
How can you compute the Python intersection of two lists accurately?
List comprehension can be used to find elements common to both lists.
a = [1, 2, 3, 4, 5]
b = [1, 3, 5, 6]
intersection = [item for item in a if item in b]
print(intersection) # Output: [1, 3, 5]
Converting both lists to sets allows you to use the intersection method for an efficient solution.
a = [1, 2, 3, 4, 5]
b = [1, 3, 5, 6]
intersection = list(set(a).intersection(b))
print(intersection) # Output: [1, 3, 5]
The filter() function filters elements from the first list based on their presence in the second list.
a = [1, 2, 3, 4, 5]
b = [1, 3, 5, 6]
intersection = list(filter(lambda x: x in b, a))
print(intersection) # Output: [1, 3, 5]
The methods effectively compute the Python intersection of two lists based on your expected output.