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From: "Bruno Luong" <b.luong@fogale.findmycountry>
Newsgroups: comp.soft-sys.matlab
Subject: Re: how do I count the permutations that were performed
Date: Tue, 25 Nov 2008 07:42:05 +0000 (UTC)
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"Gilles " <louvre65662@mypacks.net> wrote in message <ggfp59$87b$1@fred.mathworks.com>...
> How do I count the permutations that were performed during lu factorization? For instance, I get back the permutation matrix.  Is there a way I could calculate how many permutations that permutation matrix represents?

One ?  Given by the permutation matrix P. 

Your question is unclear.

Any permutation P can be decomposed as smaller independent inner circular-shift, each circular shift (length c) is in turned composed by c-1 (?) elementary swapping.

If is not very difficult to make such decomposition. But just wonder why you need it?

Bruno