Functions in Programming (Complete Beginner Guide),part 2

Types of User-Defined Functions

 

1.     Function with No Argument and No Return

In this type of Function there are no arguments and also does not return anything in back. An example of such function is as following:

v Example:

def myfunc():

print("My first function")

 

myfunc()

·       ✔ No input

·       ✔ No return

·       ✔ Only prints output

2.     Function with Argument but No Return

This type of functions have arguments but it does not return any result in back. An examples of this type of functions are:

v  Example: Even Odd function

def evenodd(x):

    if x % 2 == 0:

        print("Even")

    else:

        print("Odd")

 

evenodd(10)

·       ✔ Takes input

·       ✔ Prints result

·       ✔ No return value

v Example: Leap Year Check

def leapyear(x):

    if x % 4 == 0:

        print("Leap year")

    else:

        print("Not a leap year")

3.     Function with Argument and Return

In these type of functions the function first takes the input and also returns the output in back. An examples of such functions are as following:

v Example: Sum Function

def sum(a, b):

    return a + b

 

result = sum(2, 8)

print(result)

v Example: Multiplication Function

def mul(x, y):

    return x * y

 

result = mul(4, 6)

print("mul is:", result)

v Example: Subtraction Function

def sub(x, y):

    return x - y

 

diff = sub(3, 2)

print(diff)

v  Example: Student result example with return

def marks(x):

    if x >= 50:

        return "Pass"

    else:

        return "Fail"

 

result = marks(70)

print(result)

Output:

Pass

🔁 Function Calling

 After Defining the function we use it in the program. To use a function, we call it by its name, which we defined in the function definition. Calling a function means we are activating a function. Calling a function means executing it. It is a necessary to call a function before we use it in program.

v  Example:

myfunc()

·      Print vs Return

Feature	Print()	return
Purpose	Display Output	Sends Value
Usage	Inside Function	Inside Function
Result	Shows Immediately	Can be stored in variable

 

❓ Frequently Asked Questions (FAQs)

Q1: What is a function in simple words?

A function is a block of code that performs a specific task in a program.

Q2: Why are functions important?

They make code reusable, clean, and easy to manage.

Q3: What is the difference between print and return?

a.      "print()" shows output

b.      "return" gives output back to the program

Q4: Can a function work without return?

Yes, it works without return but it will not send any value back.

Q5: What are parameters?

Parameters are inputs given to a function so that it can perform some tasks.

 

Conclusion

Functions are a powerful feature in programming. They help us to write a clean, efficient, and reusable code.

By understanding the functions properly, we are able to take an important step towards becoming a better programmer.