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Python Python Basics (2015) Shopping List App Shopping List Introduction

Bleza Takouda
Bleza Takouda
5,129 Points
Posted by Bleza Takouda
Bleza Takouda
5,129 Points

input() vs raw_input()

I encountered a NameError when using the input function [item=input("> ")]; but it was solved when I tried the raw_input(">"). Could explain briefly the difference between both functions. Thank you .

2 Answers

William Li
PLUS
William Li
Courses Plus Student 26,868 Points
William Li
William Li
Courses Plus Student 26,868 Points

Short answer is that raw_input() in Python version 2.x was replaced with input() in Python 3.x.

The instructor is using Python 3.x for the course, my guess is that you're running Python 2.x on your own machine.

Alexander Davison
Alexander Davison
65,469 Points

I provided the long answer to avoid confusion :)

Alexander Davison
Alexander Davison
65,469 Points
Alexander Davison
Alexander Davison
65,469 Points

raw_input only exists in Python 2. raw_input in Python 2 is the same thing as input in Python 3.

However, if you try to use input in Python 2, for instance let's say I was inputting my name into a program (and I used the input function instead of the raw_input function):

What's your name? Alex

This will cause an error because Python 2 will start looking for a variable called Alex.

So, that means you could evaluate things for input (in Python 2 only):

What's your age? 15 + 16

And Python will get the input as "31".

raw_input automatically converts the input into a string, so it doesn't do all the parsing.

So, if you wanted to input "Alex" without referring to the Alex variable, you would have to put parentheses around it:

What's your name? "Alex"

But, in Python 3, to avoid confusion, Python changed the input to automatically convert the input into a string and removed the raw_input function.

However, if you want to parse the input you still can do this:

parsed_input = eval(input("What's your name? "))

I hope you understand. :)

Good luck! ~alex