How to Check if a String is a Number in Python

Submitted by razormist on Sunday, March 10, 2024 - 23:45.

In this tutorial, we will program a 'How to Check if a String is a Number in Python'. We will gain a better understanding of checking whether a string is a number. The main goal here is to understand the structure of the program for checking the string. I will provide a sample program to demonstrate the actual coding of this tutorial.

This topic is very easy to understand; just follow the instructions I provide, and you can also do it yourself with ease. The program I will show you covers the basics of programming for checking if a string is a number. I will do my best to provide you with the easiest method of creating this program, called 'Check a string'. So, let's start with the coding.

Getting Started:

First you will have to download & install the Python IDLE's, here's the link for the Integrated Development And Learning Environment for Python https://www.python.org/downloads/.

Creating Main Function

This is the main function of the application. The following code will display a simple GUI in terminal console that will display the checking of string. To do this, simply copy and paste these blocks of code into the IDLE text editor.

def checkNum(num):
    try:
        float(num)
        return True
    except ValueError:
        return False
 
while True:
    ret=False
 
    print("\n\n================= Check if a string is a number  =================\n\n")
 
    string=input("Enter here: ")
 
    if checkNum(string) == True:
        print("This a number!")
    else:
        print("This is not a number!")
    
    
    user_input=input("\n\nExit Application? (Yes/No): ")
    if user_input.lower()=='yes':
        print("Exit program.")
        break
 
    elif user_input.lower()=='no':
        ret=True
 
    else:
        print("Wrong input.")
        ret=True
 
 
    if ret:
        continue

In the provided code, we created a method that will handle the argument to check if the string is a number. Lastly, we will create a while loop that will enclose our whole block of code.

Output:

The How to Check if a String is a Number in Python source code that I provide can be download below. Please kindly click the download button.

There you have it we successfully created How to Check if a String is a Number in Python. I hope that this simple tutorial help you to what you are looking for. For more updates and tutorials just kindly visit this site. Enjoy Coding!

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