Mastering Python Function Arguments: A Step-by-Step Guide

Unlocking the Power of Python Functions: A Deep Dive

What Are Function Arguments?

In the world of computer programming, a function argument is a value that’s accepted by a function. But before we dive into the world of function arguments, make sure you have a solid grasp of Python functions.

Example 1: Demystifying Python Function Arguments

Let’s consider a simple example: the add_numbers() function. This function takes two parameters: a and b. When we call the function with add_numbers(2, 3), we’re specifying that a will take the value 2 and b will take the value 3.

The Magic of Default Values

In Python, you can provide default values to function arguments using the = operator. This means that if a value isn’t specified when the function is called, the default value will be used instead.

How Default Values Work

Let’s break down an example:

• add_number(2, 3): Both values are passed during the function call, so they’re used instead of the default values.
• add_number(2): Only one value is passed, so it’s assigned to a and the default value is used for b.
• add_number(): No values are passed, so the default values are used for both a and b.

Keyword Arguments: Assigning Values by Name

In Python, you can also use keyword arguments, where values are assigned based on the argument names. This means that the position of the arguments doesn’t matter.

Example: Keyword Arguments in Action

Consider the following function call: greet(first_name="John", last_name="Doe"). In this case, first_name in the function call is assigned to first_name in the function definition, and last_name is assigned to last_name.

Handling Unknown Numbers of Arguments

Sometimes, you might not know in advance how many arguments will be passed to a function. That’s where arbitrary arguments come in. By using an asterisk (*) before the parameter name, you can pass a varying number of values during a function call.

Example: Arbitrary Arguments in Action

Let’s create a function called find_sum() that accepts arbitrary arguments. We can then call the same function with different arguments, like this: find_sum(1, 2, 3) or find_sum(10, 20, 30, 40).

Note that after getting multiple values, the numbers parameter behaves like an array, allowing us to use a for loop to access each value.