Filter vs Reduce vs Map in Python

What are the differences between filter, reduce, and map in Python?

Which function is used for filtering elements, performing repetitive operations over pairs of iterables, and applying a function to every item in an iterable?

Final answer:

In Python, filter is used for filtering out elements, reduce is used for performing a repetitive operation over pairs of the iterable to reduce them to a single output, and map is used for applying a function to every item in an iterable and outputs a list of results.

Explanation:

In Python, filter, reduce, and map are higher-order functions that operate on lists and other iterable objects. Let me explain each of these methods for you:

• Filter: Its main purpose is to filter out elements from an iterable. It applies a function to every item in an input list, and returns a new list with only the items for which the function returned True.
• Reduce: This function performs a repetitive operation over the pairs of the iterable. It is part of the functools module in Python 3, and reduces the iterable to a single output by applying a specific function.
• Map: It applies a specified function to every item of the iterable and returns a list of the results. Unlike the filter, it doesn’t filter out elements, it just applies a function to them, transforming the elements.