Calculator Program in Python

Making evaluations and manipulating the variables to make it work as per the need is what makes Python programming an easy and significant tool.

The article below will help us to learn "how to create a calculator program in Python", where we shall explore arithmetic operators, functions in Python, and conditional statements.

Pre-requisite

Pre-requisites for creating a calculator program in Python are as follows:

• Functions in Python
• Function Arguments in Python
• User-defined Functions in Python
• Knowledge of tkinter in Python

Simple Calculator Program in Python

Let's learn "How to make a simple calculator in python?"

We shall be breaking down our process of creating the calculator program in Python into simple steps. To help understand the concepts in depth, create a simple calculator program in Python that can perform basic mathematical operations such as addition, subtraction, multiplication, or division, all of which depend upon the input given by the user.

Let us dive in and learn by executing each step towards creating a calculator program in Python.

Step 1: Prompting Input from the User, we shall accept input for two variables.

In this step, we shall take the user's input using Python's input() function. It is the same as when we enter numbers in an accurate calculator to perform arithmetic operations. We shall ask the user to input two variables using each variable's input() function.

Let's have the program perform the prompt for the two numbers:

Code:

Output:

Step 2: Define and Add operators or functions such as add(), subtract(), multiply() and divide() to estimate respective functions.

Now we are adding the functions to perform the mathematical operations such as addition, subtraction, multiplication, and division to create the computation for the calculator program in Python. We also modified our input functions as integers to guide the user to perform the arithmetic operations only on integers, not strings.

Code:

Output:

Above, we have described each of the four basic arithmetic operations in Python using the format() function. format() functions fill the placeholder and make the output formatted. The user's input was now computed for each of the arithmetic operations we defined.

As all the functions are getting executed described for the two numbers, we have to make it work per the user's choice. We shall be using conditional statements - if…elif…else branching so that it only performs the operations based on the user's choice of operation like in an accurate calculator.

Step 3: To make it similar to a calculator, apply conditional statements (if…elif…else branching) to make it work as per the User's choice

To make it the user's choice, we shall define each arithmetic operation as a function using the def function in Python. We will again ask for the user's input for the mathematical operations that they want to perform.

Code:

Output:

Bravo!!! We made our calculator program in Python based on the user's choice of input of numbers and operators, exactly how a real calculator works.

Python Program to Make GUI Calculator

Let's learn "how to create GUI Calculator in Python?" Here are the step-by-step instructions to create a GUI calculator in Python using Tkinter, along with the corresponding code:

Step 1: Import necessary libraries

Step 2: Create the main window

Step 3: Create a frame

Step 4: Create an Entry widget

Step 5: Define functions for buttons

Step 6: Create number buttons

Step 7: Create operator buttons

Step 8: Create clear and equal buttons

Step 9: Run the GUI

Step 10: Final program

This completes the step-by-step guide and the corresponding code to create a simple GUI calculator in Python using Tkinter.

See Also

• Factorial Program in Python
• Factorial Using Recursion in Python