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From: tristram.scott@ntlworld.com (Tristram Scott)
Subject: Re: Is a QR Decomposition Better than B \ A?
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Date: Fri, 13 Jul 2007 14:19:59 GMT
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John D'Errico <woodchips@rochester.rr.com> wrote:
> Randy Yates wrote:
>>
>>
>> If we have a system of equations Ax=b, then we can solve it using
>>
[snip]

> 
> x = R\*(Q'*b);

A Rantmode induced typo, I think.

x = R \ (Q'*b);

> 
> Since R is upper triangular, \ is FAR more
> efficient here.
> 
> 

Excellent rant!

-- 
Dr Tristram J. Scott               
Energy Consultant