Basics of Python-13

Day-13

Function :

Python function is a block of code to make the code easier and to do the specific task.

there are two types of functions in python -:

Built-in function

User-defined function

Basics syntax of function :

def function_name(parameter):

statement

return expression

Built-in Functions in python:-

This type of function in python comes along with python software automatically.

some examples of built-in functions are :

print() - used to print values to the console

len() - used to get the length of a string, list, tuple, dictionary, or set

type() - used to get the type of a variable

input() - used to get user input from the console

int() - used to convert a string or float to an integer

float() - used to convert a string or integer to a float

str() - used to convert a variable to a string

range() - used to generate a range of numbers

list() - used to convert a sequence (e.g. a tuple) to a list

max() - used to get the maximum value in a sequence.

User-defined Functions in python :

User-defined functions can be developed on their own.

An example of a user-defined function is:

Function to add two numbers:

def add_numbers(x, y):

return x + y

the basic syntax is :

def function_name(parameter):

Let's solve a few problems on function:

Write a python program to find odd and even numbers by using functions in python -

def is_even(num):
    if num % 2 == 0:
        return True
    else:
        return False
n = int(input("Enter a number: "))
if is_even(n):
    print(n, "is even")
else:
    print(n, "is odd")

output :

Write a python program to print a calculator program by using the python function -

def add(x, y):
    return x + y

def subtract(x, y):
    return x - y

def multiply(x, y):
    return x * y

def divide(x, y):
    if y == 0:
        return "Cannot divide by zero"
    else:
        return x / y


num1 = float(input("Enter first number: "))
num2 = float(input("Enter second number: "))
print("Select operation:")
print("1. Add")
print("2. Subtract")
print("3. Multiply")
print("4. Divide")
choice = input("Enter choice (1/2/3/4): ")
if choice == '1':
    print(num1, "+", num2, "=", add(num1, num2))

elif choice == '2':
    print(num1, "-", num2, "=", subtract(num1, num2))

elif choice == '3':
    print(num1, "*", num2, "=", multiply(num1, num2))

elif choice == '4':
    print(num1, "/", num2, "=", divide(num1, num2))

else:
    print("Invalid input")