Percentage matching of text

[Steve Christensen]

In article <mailman.958.1091195562.5135.python-list at python.org>, Bruce
Eckel wrote:
> 
> What I'd like to do is find an algorithm that produces the results of
> a text comparison as a percentage-match. Thus I would be able to
> assert that my test samples must match the control sample by at least
> (for example) 83% for the test to pass. Clearly, this wouldn't be a
> perfect test but it would help flag problems, which is primarily what
> I need.
> 
> Does anyone know of an algorithm or library that would do this? Thanks
> in advance.
> 

Have you come across the following yet?

Levenshtein C extension module for Python:
http://trific.ath.cx/resources/python/levenshtein/


And/or:
http://hetland.org/python/distance.py


-Steve