Check character is digit using 'isdigit()'

Check character is digit using ‘isdigit()’ in Python

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In this tutorial we are going to check if the character is Digit ( 0-9) or not using isdigit() function in python.

Problem statement

For the any input character we have to check character is digit or not.

For example:

Case 1: If user is given input 1

              Output should be “Digit”

              As we know that 1 is digit

Case2: If user is given b or B

             Output should be “Not a Digit”

             As we know that B is a Alphabet not a digit.

Our logic to check given character is digit or not using ‘isdigit()’ function

  • Our program will take any character as an input from the user and then checks if the input character is a digit or not.
  • To check the input character, if it is a digit or not, we use a built-in in python called isdigit() which verifies the input.
  • And returns the Boolean value as “True” for digit and “False” for any other character.  

Algorithm to check given character is digit or not using ‘isdigit()’ function

Step1:  Start

Step2:   Take a character as an input from user and store it in “ch” variable.

 Step3:   Apply the condition,

                        If ch.isdigit():

                                    Print (‘Digit’)

                          else:

                                  Print(’Not a Digit’)

Step4:  Stop

Python Code to check given Character is digit or not using ‘isdigit()’ function

# taking input from user
ch = input("Enter a character : ") 
# checks if character ‘ch’ is digit or not
if(ch.isdigit()): 
     #if ‘ch.digit()’ returns “True”
    print("The Given Character ", ch, "is a Digit")
else:
      #if ‘ch.digit()’ returns “False”
    print("The Given Character ", ch, "is not a Digit")

Output 1:

Explanation :

In this case, the user has given 5 as an inputs, and the code generate the output as “The Given Character 5 is a Digit”. This shows the 5 is a numerical value, which is true. In the ‘condition’ block of our program, ch.isdigit() returned true for character ‘5’. So the ‘if’ block executes and the desired output is generated.

Output 2:

Explanation :

In this case, the character input given by the user is ‘C’. The condition block of ‘if’ statements will check for input character using the isdigit() method, which returns “False” as character ‘C’ is an alphabet, not a digit. This fails the ‘if’ block so ‘else’ is executed to print the required output.