installing IPython with two versions of Python (Windows)

Question

Is it possible to have IPython (0.12) installed on the same system with two different versions of Python (v 2.7 and 3.2)? Currently I have both versions of Python running happily on my system.

I am using two machines, one with Windows 7 64-bit, the other XP SP2 32-bit, and both have Python 2.7.2 and 3.2 installed. I have been using IPython with Python 2.7 w/o any problems for a while on both.

Now I would like to have 3.2 available too with IPython, but when I try to run the binary windows IPython installer I get this error toward the end of the install:

*** run_installscript: internal error 0xFFFFFFFF ***

and no shortcuts/entries into Start Menu etc are created. (I ran the install as adminstrator under Win 7) I am running into the same problem with XP and Win 7.

After poking around the net and SO for a while I saw references for getting setuptools. Unfortunately, there's no version for Python 3.x but it was suggested to use distribute.py instead which I ran and installed. I am not sure how to proceed next. And I'm not even sure it is possible to do this (though I think it is :)

Any suggestions?

UPDATE: There was a problem with import readline not working with Python 3.2.3, but I was able to fix it by downloading pyreadline-2.0-dev1.win32.exe which works with Python 3.2.3 .. the above problem remains unfortunately.

Answer 1

Ok, here's my solution to get IPython 0.12.1 to work with both Python ver 2.7.x and 3.2.x on the same system (ie. under Windows 7 64 bit and XP SP2 32 bit). It's not perfect, but works, and hopefully will help others. Where I am showing directories they refer to XP (but should be adjusted accordingly for Windows 7)

Steps for both:

1. Install both versions of Python via the binary windows installer provided at Python.org

2. Install this version of pyreadline pyreadline-2.0-dev1.win32.exe which works for both versions of Python (I could not get the widely available version 1.7 to work with Python 3.2.x)

3. I am not sure if distribute.py is necessary, I'd skip it on the first try.

4. Download ipython-0.12.1.zip file and extract it. Place it under your Programs directory and cd into it (I'll call this the ipython_dir) [I tried the binary installer numerous times without success]

For Python 3.2 (easier)

In the ipython_dir:

c:\python32\pyton.exe setup.py install

will create ipython3.exe in c:\python32\Scripts that can be used to fire up iPython

For Python 2.7 (a bit odd)

The above method failed. However, it is possible to start IPython from the ipython_dir with

c:\python27\python.exe  ipython.py

I can't explain why this is so, but since I use Console2 I can hide these two ways of starting IPython.

Summary:

To start IPython with v 2.7.x of Python:

c:\python27\python.exe "C:\Program Files..\ipython_dir\ipython.py"

To start IPython with v 3.2.x of Python:

c:\python32\Scripts\python3.exe

That was a lot of work and took most of the day, so I hope posting the steps above will save someone else a lot of time (and help me remember what I have to do next time I struggle with this)

Thanks everyone for their suggestions.

Addendum: None of the above resulted in shortcuts or entries in the Start/Program Menus. Shortcuts can be created manually, or in my case aren't necessary since I'm using a special shell (Console2) to run IPython.

Answer 2

The first question in the iPython FAQ titled "Running IPython against multiple versions of Python" may help.