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From: "John D'Errico" <woodchips@rochester.rr.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Uniform random rotation matrix
Date: Thu, 9 Dec 2010 21:47:05 +0000 (UTC)
Organization: John D'Errico (1-3LEW5R)
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"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <idri4m$nuc$1@fred.mathworks.com>...
> "John D'Errico" <woodchips@rochester.rr.com> wrote in message 
> > On the other hand, is either of these methods
> > truly random in their result? Try this...
> > > ...
> >   [q,~] = qr(randn(2) - 0.5);
> 
> The above has flaw, but my original method without shifting
> 
> > [q,~] = qr(randn(2));
> 

Yes it does have a flaw. Have you tried my example
for randn?

LOOK AT THE RESULT. Does it look unbiased?

John