running same script on same data on two different machines --> different result

[Steven D'Aprano]

On Fri, 14 Nov 2008 07:14:20 -0800, Christopher Brewster wrote:

> I am running the same script on the same data on two different machines
> (the folder is synchronised with Dropbox). I get two different results.
> All the script does is count words in different files and perform a
> simple set operation on the word lists. The laptop is a Macbook Pro (2
> 1/2 years old) running OS X 10.5.5 with Python 2.5.1
> The desktop is an iMac (brand new) running OS X 10.5.5 also with Python
> 2.5.1
> 
> I have tried running the script on an ubuntu server with Python 2.5.2
> and the results corresponded with my laptop's output. How can I find out
> the cause of this anomaly? What tests can I perform?

Try eliminating files and see if you can narrow the problem down to a 
single file.

Make sure the files really are synchronized. Try comparing their md5 
checksums.

Create a batch of test files, copy them from one machine to the other, 
and then confirm that the script calculates the same result.

Lastly, make sure that both machines really are using the same script!

And if you do find the result, please let us know... I'm intrigued.



-- 
Steven