Functional Programming Fundamentals: Lambda Expressions and Map

Learning Objectives Define what a lambda expression is and its purpose in Python. Write a simple lambda expression that takes one or more arguments to perform a single operation. Explain the purpose and functionality of the built-in map() function. Use the map() function with a lambda expression to transform each item in a list. Convert a map object into a list to view and use its contents. Compare a traditional for loop approach to the map() and lambda approach for transforming data. Ever wanted to write a tiny, one-line function to do a quick job, like doubling every number in a list? 🚀 What if you could do it without even giving the function a name? In this lesson, you'll discover a powerful style of programming called functional programming. We'll learn about...

TermDefinitionExample Functional ProgrammingA style of writing code by creating and combining small, predictable functions. Think of it like building with LEGOs: each function is a block that does one thing well and doesn't interfere with other blocks.Instead of a loop that changes a list, you create a new list by applying a function to the old one. This avoids side effects and can make code easier to understand. Lambda ExpressionA small, unnamed function defined with the `lambda` keyword. It can take any number of arguments but can only have one expression (one line of code). It's also called an 'anonymous function'.lambda x: x * 2 (This is a function that takes an argument `x` and returns `x` multiplied by 2). map() functionA built-in Python function that applies a...

Lambda Expression Syntax lambda arguments: expression Use the `lambda` keyword to start. List the `arguments` (inputs) before the colon. After the colon, write the single `expression` that will be performed and returned. Map Function Syntax map(function, iterable) Use `map()` to apply a `function` to every item in an `iterable` (like a list). The `function` can be a regular named function or, very commonly, a lambda expression. Viewing Map Results list(map(function, iterable)) The `map()` function returns a map object, not a list. To see the results, you must wrap your `map()` call with `list()` to convert the object into a list.