From octave-maintainers-request at bevo dot che dot wisc dot edu Fri Mar 12 02:00:22 2004
Subject: Left division operator
From: "Pascal A. Dupuis" <Pascal dot Dupuis at esat dot kuleuven dot ac dot be>
To: octave-maintainers at bevo dot che dot wisc dot edu
Date: Fri, 12 Mar 2004 08:59:04 +0100

Hello,

from octave doc, it is said that the left division operator can be
used to solve overdetermined problems: find x  which minimises
norm(Ax-B) => x=A\B

It is also stated that it does not compute the inverse of
A. Translation: it does not use the normal equation (A'*A)*x=A'*B. Right ?

Just curious: which proceduce is used ? Householder transformation of
A? Singular values decomposition ? Other ? In fact, this matters
mainly in the case of a badly conditionned A (nearly linear dependance
between columns).

TIA

Pascal

-- 
Dr. ir. Pascal Dupuis
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