Question

“Starting Out with Python”, Chapter 5, introduces the student to functions. Describe in your own words some ways functions are beneficial to the programmer. In other words, why might a programmer want to use functions?

Answer 1

Hey There,

- I understood your question and I gave my answer to the best of my knowledge.

- If you need further explanation then do let me know in the comments box. I will be more than happy to help you:)

Answer:

- Basically a Function is a group of statements that perform a specific task. We use functions in python to bundle a set of instructions that we want to use repeatedly.

- If we have a very long code then by using the concept of the function we can divide our whole code into smaller and modular chunks.

- If there is a case where we are making some kinda reputation in our code then instead of writing the code again and again we can define a function and then reuse it.

- Functions increases the readability of the code.

- There are 3 types of functions in python:

1. Built-in functions
2. User-Defined functions
3. Lambda functions (Anonymus functions)

- Now, let's understand the usage of function practically:

• Suppose you want to write a program that calculates simple interest for the values that user entered. And you want to run this program until user enters -1. So here instead of writing the code again and again we can define a function that takes n, p, and r as an argument and return the simple interest for these values.
• Syntax:   

def calculate_simple_interest (n, p, r):
    # Code to calculate simple interest

    return simple_interest

• One simple example to use function would be that we want to write a program that calculate HCF of 2 numbers. Now if we want to make our program dynamic then we can define a function "calculate_HCF" which will calculate the HCF for given numbers.
• Syntax:

def calculate_HCF(num1, num2):
    # Code to calculate HCF of 2 numbers

    return HCF

• There are a lot of built in functions available that can ease our work. Like enumerate(), abs(), filter(), etc. Even the print() is an inbuilt function.

- We can see that the function is very beneficial for the programmer as it increases readability, avoids repetition, encourages the idea of reusing, etc.

Hope it helps:)