Code works in one Python environments but has a syntax error in another

Question

I am working on the following code:

def numberToName(number):
    if (number==3):
        return "Three"
    elif (number==2):
        return "Two"
    elif (number==1):
        return "One"
    else:
        return "Invalid"

print numberToName(2)
print numberToName(3)
print numberToName(1)
print numberToName(1)

This code runs 100% fine in the following online Python environment - http://www.codeskulptor.org/#user11_Hh0KVUpNVP_0.py

But when I use IDLE it shows a syntax error Invalid Syntax in line print numberToName(2)

My Python version is 3.3.1

I have noticed some issues as well. For an example, in the given URL, I can run print "hello" and get the output, but the same generated error in IDLE unless I type print ("Hello").

What is the issue here? I am new to Python.

(Please note the main question is about the given code snippet).

If you plan to learn Python 3.3 (which is a good idea), you're going to want to find an online Python 3.3 interpreter. There are a bunch of them out there if you search. There's even an online [interactive visualizer](http://pythontutor.com/visualize.html#) that handles 3.3. — abarnert, May 02 '13 at 20:17
Also, if you don't know which Python version you're using, you can always do this: `import sys; print(sys.version)`. This line of code works with both 3.x and 2.x (and even 1.x, in case you accidentally fall through a Primeval-style temporal anomaly). — abarnert, May 02 '13 at 20:21
@msw: Wow, that's all kinds of weird. I love their handling of complex numbers—`j` is a legal suffix for numbers, but means nothing. So, e.g., `1+2j` is `3`. Imagine how easy (and useless) trig class would be… And simulating bitwise operators on floats is especially clever; you can prove that `((1 << 64) + 1) & 1) == 0`. — abarnert, May 02 '13 at 21:09
@msw: No, it is a python environment. It is built by Rice University, specially for their online course in here https://www.coursera.org/course/interactivepython. I am also a student there — PeakGen, May 03 '13 at 05:21
It's a Python-like environment. If you come here and ask why Python is telling you `((1 << 64) + 1) & 1) == 0` and `not dir(dict)` are True, people will waste time trying to figure out that you're running a simulation of Python written in javascript. Clever? Sure. Python? Nope. — msw, May 03 '13 at 08:34

score 4 · Answer 1 · answered May 02 '13 at 20:08

4

The online environment is Python 2. Your IDLE install is Python 3.

There are many differences, in this case the issue is that print is now a function.

See also: http://python3porting.com/

answered May 02 '13 at 20:08

Lennart Regebro

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Thanks for the reply. But, why the other function calling in my code made issues? Please help! – PeakGen May 02 '13 at 20:14
ah I got it, thanks! +1 from me! – PeakGen May 02 '13 at 20:17

eandersson · Accepted Answer · 2013-05-02T20:30:04.423

3

That is because the IDE is using Python 3.X, and not Python 2.X like in the online environment.

In Python 2.X you can use print("test") or print "Text".

In Python 3.x you need to use print("test").

This is because in Python 2.X print is a keyword, and not a function, while in Python 3 it is a function.

If you change the print functions to this, it will run on both the web application and your IDE.

print(numberToName(2))
print(numberToName(3))
print(numberToName(1))
print(numberToName(1))

edited May 02 '13 at 20:30

answered May 02 '13 at 20:09

eandersson

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Thanks for the reply. But, why the other function calling in my code made issues? Please help! – PeakGen May 02 '13 at 20:15
If you change the print lines to `print(numberToName(2))` it should run in your IDE. – eandersson May 02 '13 at 20:16
@Yohan This code will run in both the IDE and the online compiler http://www.codeskulptor.org/#user11_RAR5KMSUd4IHJMq.py – eandersson May 02 '13 at 20:28

score 3 · Answer 3 · answered May 02 '13 at 20:10

3

The site you link to uses python 2.6 as they state.

print is no longer a statement in python 3, but rather a function, which means it must be called with parenthesis: print(...).

answered May 02 '13 at 20:10

azgult

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10

score 1 · Answer 4 · answered May 02 '13 at 20:12

1

The difference between print 'word' and print('word') was one of the big changes from 2.x to 3.x. To fix it, just treat print as a function and it will work.

answered May 02 '13 at 20:12

erdekhayser

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Code works in one Python environments but has a syntax error in another

4 Answers4