What are some real-world examples of using map and filter in programming?

Can you give me some real-world examples of using map and filter in programming?

Sure! The map function is often used to transform data, like converting a list of temperatures from Celsius to Fahrenheit. The filter function can be used to select items from a list, such as filtering out even numbers from a list of integers.

That sounds interesting! Can you show me a code example for both?

Absolutely! Here's a Python example:

# Using map to convert Celsius to Fahrenheit
celsius = [0, 10, 20, 30]
fahrenheit = list(map(lambda x: (x * 9/5) + 32, celsius))

# Using filter to get even numbers
numbers = [1, 2, 3, 4, 5, 6]
even_numbers = list(filter(lambda x: x % 2 == 0, numbers))

In this code, map transforms the Celsius list, and filter extracts even numbers.

Can you explain how the lambda function works in these examples?

Sure! A lambda function is an anonymous function defined with the lambda keyword. It can take any number of arguments but can only have one expression. In the examples, lambda x: (x * 9/5) + 32 converts Celsius to Fahrenheit, while lambda x: x % 2 == 0 checks if a number is even.