Question

Discuss Exercises #1 on page 171: Anne complains that defining functions to use in her programs is a lot of extra work. She says she can finish her programs much more quickly if she just writes them using the basic operators and control statements. State three reasons why her view is shortsighted. Explain why functions are useful in structuring code in a program.

Answer 1

Lets first write some general statements as to why functions are important.
- Function provide readability in the code.
- Functions avoid redundancy in the code.
- Program is broken down in sub parts of functions which is easy to understand by any new joiner.
- Name of function directly refers to the work that a function does (convention). So, just by looking at function , we can come to know about the overview of code it computes.


1.) Lets take an example where we need to write a code that computes average , max , min of students marks based on user input. Enter 1 - > Avergae. 2 -> Max. 3 -> Min 4-> exit

Consider the below steps in case no function is involved
- Show menu on screen by writting print statements.
- Take input from user
- Open and read file
- Does the calculation

- These steps are for one user. This menu has to be shown until user exits. In this case, we have to keep on writting the print statements for the menu. Number of print statements will be N where N is number of times user does an action.


Consider the below steps is case function is involved
- Call function to show menu
- Call funtion to take user input and return a value.
- Return contents of file from a function.
- Calls another function that computes the result and return it to the caller.

Here, we have to just define all the cases only ONCE. In every case, we just call the method and get the result.


2.)
Modifications - > In case we want to debug the code and we know there is some error in a portion of code, it is always easier to maintain the code if one logical set of code is seperated from another set of code.

3.)
Code growth -> It is okay if the lines of code of a program are 10-100 or even in thousands. But, this is not a practical case. In a real life project, the lines of codes are in lakhs. To maintain that huge amount of code, we need some logical segregated approach to identify any issues or make any code changes.

4.)
Reusability -> If same snippet is required at some other place in a project/program, we need to write that again. So, better have functions. Just pass a value to it and get the result without having to write code again.



*Kindly upvote if this helped