A simple Calculator Using Python

Hello viewers,
Today I am gonna show you a simple code to help you make a calculator using Python programming language.

There are a number of ways of doing this.The man idea behind this code is to teach you how to write functions in Python.

The syntax goes like this

Syntax

def functionname( parameters ):
   "function_docstring"
   function_suite
   return [expression]

By default, parameters have a positional behavior and you need to inform them in the same order that they were defined.

Example

The following function takes a string as input parameter and prints it on standard screen.

def printme( str ):
   "This prints a passed string into this function"
   print str
   return

The calculator code here:

''' Program make a simple calculator that can add, subtract, multiply and divide using functions '''

# define functions
def add(x, y):
   """This function adds two numbers"""
   return x + y

def subtract(x, y):
   """This function subtracts two numbers"""
   return x - y

def multiply(x, y):
   """This function multiplies two numbers"""
   return x * y

def divide(x, y):
   """This function divides two numbers"""
   return x / y

# take input from the user
print("Select operation.")
print("1.Add")
print("2.Subtract")
print("3.Multiply")
print("4.Divide")

choice = input("Enter choice(1/2/3/4):")

num1 = int(input("Enter first number: "))
num2 = int(input("Enter second number: "))

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")

Output
Select operation.
1.Add
2.Subtract
3.Multiply
4.Divide
Enter choice(1/2/3/4): 3
Enter first number: 15
Enter second number: 14
15 * 14 = 210


In this program, we ask the user to choose the desired operation. Options 1, 2, 3 and 4 are valid. Two numbers are taken and an if...elif...else branching is used to execute a particular section. User-defined functions add(), subtract(), multiply() and divide()evaluate respective operations.





If you have any doubts regarding the above code Feel free to comment in the comments section provided below.



Thank you! Stay tuned on this blog for more posts.