Functions and Recursion in PYTHON

A Function is a group of statements performing a particular task.

When a program gets bigger in size and its complexity increases, it gets difficult for a programmer to keep track on which piece of code is doing what ! A function can be reused by the programmer in a given program any number of times as he wants.

Syntax of a Function in Python :-

def func():

print("Hello")

#this function can be called any number of times.

Function cell :-

Whenever we want to call a function we put the name of the function as 'def func_name():'

Function definition is the exact set of instruction which are to be excuted.

Lets write an easy code :-

It was an easy program, lets see some other examples :-

Now we will make a programme of summation using function :-

Now we will see a complicated problem, So that you can understand better :-

Now we have to write a program to find the maximum of three numbers using function :-

Now I hope you understand Functions.

Recursion :-

Recursion is a function which calls itself. It is used to directly use a mathematical formula as a function.

Let first code it with simply using function and after it with recursion:

Now lets try the above program with the help of recursion :-

Hope you understand about Functions and Recursion. Please share it with your friends and help them learning python. In the next tutorial we will learn about some sorting algorithms like Bubble sort and Insertion sort.

John Veer

Contact mail id - john.veer.utube@gmail.com

Thanks for reading !

Comments

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