Here we will see the different ways to filer a list in python.

How to filter a list in python?

We see it is very frequently, filtering a list with a specific condition(s), in python we can filter the list in a couple of ways. Let’s see them.

filter()

As the name itself suggest, the filter() function filters a list on a given condition. The filter() is a Python built-in function hence we don’t need to install the python package to use it.

filtering even numbers.

numbers = [1, 2, 3, 4, 5, 6, 7]

even_numbers = list(filter(lambda item: item % 2 == 0, numbers))

print(f"Even numbers: {even_numbers}")

In the above example, we have a list with some numbers, using filter() function we get the even numbers out of it. The filter takes a lambda expression to filter the collection.

Basically the filter()function returns the filter object, to make it iterable we converted the filter to a list.

Output:

Even numbers: [2, 4, 6]

filter using for loop:

We can also filter the list using for loop, but while taking advantage of the pythonic way of writing the code, we can accommodate this task with a single lined for loop.

even_numbers = [number for number in numbers if number % 2 == 0]
print(f"even numbers : {even_numbers}")

Output:

even numbers : [2, 4, 6]

References:

Happy Learning 🙂