What is the difference between map and filter in programming?

What is the difference between map and filter in programming?

The map function applies a given function to each item in a list, returning a new list. filter, on the other hand, creates a new list containing only the items that pass a certain condition.

Can you give me an example of how to use both?

Sure! For map, if you have a list of numbers and want to double them, you can use map like this: map(lambda x: x * 2, numbers). For filter, if you want to keep only even numbers, you can use: filter(lambda x: x % 2 == 0, numbers).

Are there any performance differences between them?

Yes, map is generally faster for applying a function to all items, while filter can be more efficient when you only need a subset of items, as it stops processing once it finds all matches.

Can I chain them together?

Absolutely! You can chain them like this: list(map(lambda x: x * 2, filter(lambda x: x % 2 == 0, numbers))) to first filter even numbers and then double them.