How to Get User Input in Python from Keyboard?

We already know, Programming is all about processing data. To process the data program needs information as an input. It can come from many ways.as from a database or other machine/device/website or mouse hover/clicking.

Such as,

• input from the database
• information from external resources like machine/device/website
• by typing on the keyboard
• hovering or clicking by mouse

In this post, we are only interested in getting keyboard input from the user.

How to Get User Input in Python?

There are two different inbuilt functions to read user input.

• raw_input()
• input()

Here in this post, we check out, how to receive input from the keyboard.  And what is the difference between ‘raw_input()’ and input() function?

Python 2: Getting command line input using ‘raw_input()’

There is function raw_input(). Name itself depicts as it read raw data. It read user data as a string. It does not have the intelligence to interpret the type of data; the user has entered.

 name = raw_input('Enter your keyboard input:') 

All the data until you press the return key, will be read by this function.

By default, raw_input read the input data and gives in the form of a string.

Note: It is an in-built function, so you don’t need to import any external library.

Python 3: Keyboard input from the user using ‘input()’

It provides in build function ‘input()’ to read the input from the user.

name = input("What's your Good name? ")

Function input() reads the data from the user and interprets data according to the type of data entered by the user.

If the user enters integer/float value, it preserves the data type of input. It return same as integer/float value, unlike to raw_input() function.

Function input() is consider to be an intelligent function for its datatype interpretation.

Let’s start exploring it further.

What is the difference between input and raw_input function?

If you want to get input as integer or float in Python 2, you need to convert data into int or float after reading data using raw_input().

mode=int(raw_input('How old are you?:'))

As we are taking input from the user, we can not ensure if the given user input value type is numeric data type (float or int) or not.

So it is good practice to catch the error using try and except.

try:
    mode=int(raw_input('Keyboard Input:'))
except ValueError:
    print "This is not a number."

Another way is you can check the data type of the input using isdigit().

mode = raw_input('Keyboard Input:')
 if(mode.isdigit())
     "Number is integer."
 else
     "Number is not a integer."

Handling error is good practice to prevent code from crashing at runtime.

How to Get User Input in Python for Both Python version?

But now real confusion starts from here.

What about if you do not know the python version to whom you are going to run your code? Or do you want the code to run on both Python version?

It’s simple. Just check the version of the python and then put the if else statement to distinguish python input function as per the Python version.

Suppose if you are running code on Python 2.x, it should use raw_input() function to read user value. If the same is going to run on Python 3.x environment, it should use the input() function.

So the first task is to find the Python version number.

To get the Python version, you need to import sys module.

Use the following code snippet to read user input for both python version.

from sys import version_info

python_3 = version_info[0]

#creates Boolean value 
#for test that Python major version

if python_3:
     response = input("Please enter your Good Name: ")
 else:
    response = raw_input("Please enter your Good Name: ")

Conclusion:

• Python 2.x has raw_input() function to get keyboard input. Likewise, Python 3.x has function input().
• The input() function has more intelligence to interpret the user input datatype than raw_input() function.
• If you want your code to work on both Python version, use condition by checking its python version.

Hope you got the solution, how to Get User Input in Python for both Python 2 and Python 3 version. If you have any question, feel free to ask me in a comment.

You can read my post on  3 Types of Programmer needs for Software Developer Jobs in Future.

Happy Coding!