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Pulling all n-sized combinations from a list

mensanator at aol.com mensanator at aol.com
Thu Feb 9 13:23:12 EST 2006 
Jack Diederich wrote:
> On Wed, Feb 08, 2006 at 12:50:19PM -0800, Swroteb wrote:
> > Hi there,
> >
> > I've got a reasonably sized list of objects that I'd like to pull out
> > all combinations of five elements from.  Right now I have a way to do
> > this that's quite slow, but manageable.  I know there must be a better
> > way to do this, but I'm not sure what it is.  Here's what I've got so
> > far:
> >
>
> import probstat # http://probstat.sourceforge.net
> for (a, b, c) in probstat.Combination(range(9), 3): # 0..9, pick 3
>   print a, b, c
>
> It is a C extension that does permutations & combinations and is
> about 10x faster than doing it in pure python [I'm the author].
> It is also the 3rd result for "python combination" and 5th for
> "python permutaiton" but every month someone posts to c.l.py asking
> for something similar.  Go figure.

Did you ever figure that some people use Windows?

> 
> -jackdied
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