Differences Between 'Input' and 'Raw_Input'

What's the difference between `raw_input()` and `input()` in Python 3?

The difference is that raw_input() does not exist in Python 3.x, while input() does. Actually, the old raw_input() has been renamed to input(), and the old input() is gone, but can easily be simulated by using eval(input()). (Remember that eval() is evil. Try to use safer ways of parsing your input if possible.)

Differences between `input` and `raw_input`

In python 2.x, raw_input() returns a string and input() evaluates the input in the execution context in which it is called

>>> x = input()
"hello"
>>> y = input()
x + " world"
>>> y
'hello world'

In python 3.x, input has been scrapped and the function previously known as raw_input is now input. So you have to manually call compile and than eval if you want the old functionality.

python2.x                    python3.x

raw_input()   --------------> input()               
input()  -------------------> eval(input())     

In 3.x, the above session goes like this

>>> x = eval(input())
'hello'
>>> y = eval(input())
x + ' world'
>>> y
'hello world'
>>> 

So you were probably getting an error at the interpretor because you weren't putting quotes around your input. This is necessary because it's evaluated. Where you getting a name error?

Is it ever useful to use Python's input over raw_input?

Is it ever useful to use Python 2's input over raw_input?

No.

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input() evaluates the code the user gives it. It puts the full power of Python in the hands of the user. With generator expressions/list comprehensions, __import__, and the if/else operators, literally anything Python can do can be achieved with a single expression. Malicious users can use input() to remove files (__import__('os').remove('precious_file')), monkeypatch the rest of the program (setattr(__import__('__main__'), 'function', lambda:42)), ... anything.

A normal user won't need to use all the advanced functionality. If you don't need expressions, use ast.literal_eval(raw_input()) – the literal_eval function is safe.

If you're writing for advanced users, give them a better way to input code. Plugins, user modules, etc. – something with the full Python syntax, not just the functionality.

If you're absolutely sure you know what you're doing, say eval(raw_input()). The eval screams "I'm dangerous!" to the trained eye. But, odds are you won't ever need this.

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input() was one of the old design mistakes that Python 3 is solving.

How do I use raw_input in Python 3?

Starting with Python 3, raw_input() was renamed to input().

From What’s New In Python 3.0, Builtins section second item.

Difference of input() in python2/3

Data type of answer is string, After changing it to int it will work fine

import random
import sys

#display the python version
print(sys.version)

#computer selects two random numbers between 1 and 10
x = random.randint(1,10)
y = random.randint(1,10)

#print x and y values
print("For x =", x, "and y =", y)

#calculate the correct answer to the sum of the two numbers and store it in the variable named "correct"
correct = x + y

#ask the user what is the sum of the two random numbers and provide a response
answer = input("What is the sum of x plus y ? ")
if(int(answer)==correct):
    print("well done")
else:
    print("Incorrect. The correct answer is", correct)

Differences between input commands in Python 2.x and 3.x

In Python 3.x, raw_input became input and Python 2.x's input was removed. So, by doing this in 3.x:

text = input('Text here')

you are basically doing this in 2.x:

text = raw_input('Text here')

Doing this in 3.x:

text = eval(input('Text here'))

is the same as doing this in 2.x:

text = input('Text here')

Here is a quick summary from the Python Docs:

PEP 3111: raw_input() was renamed to input(). That is, the new input()
function reads a line from sys.stdin and returns it with the trailing
newline stripped. It raises EOFError if the input is terminated
prematurely. To get the old behavior of input(), use eval(input()).

raw_input function in Python

It presents a prompt to the user (the optional arg of raw_input([arg])), gets input from the user and returns the data input by the user in a string. See the docs for raw_input().

Example:

name = raw_input("What is your name? ")
print "Hello, %s." % name

This differs from input() in that the latter tries to interpret the input given by the user; it is usually best to avoid input() and to stick with raw_input() and custom parsing/conversion code.

Note: This is for Python 2.x

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