Lambda functions

A lambda function is a small, anonymous function that can be defined in a single line. It is also known as an "anonymous function" because it doesn't have a name like regular functions.

Lambda functions are typically used when you need a simple function for a short period of time and don't want to define a separate function using the def keyword. They are commonly used in combination with built-in functions like map(), filter(), and reduce().

The basic syntax of a lambda function consists of the lambda keyword, followed by the arguments (separated by commas), a colon :, and the expression that defines the function's behavior. Here's an example:

multiply = lambda x, y: x * y

In this example, we define a lambda function called multiply that takes two arguments x and y and returns their product. The expression x * y defines the behavior of the function.

Lambda functions are often used as one-liners, where they are defined and used in the same line. Here's an example using the map() function:

numbers = [1, 2, 3, 4, 5]
squared_numbers = list(map(lambda x: x**2, numbers))

In this code, we use a lambda function to square each number in the numbers list. The map() function applies the lambda function to each element of the list, and the list() function converts the result into a list.

Lambda functions are particularly useful when you need to define a simple function on the fly without the need for a formal function definition. However, they have some limitations. Lambda functions can only contain a single expression, and they cannot include statements or multiple lines of code.

It's important to note that while lambda functions can be convenient, it's also important to write code that is clear and easy to understand. For more complex operations or functions with multiple lines of code, it's generally better to use regular functions defined with the def keyword.