lscov vs \
in [Matlab]
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From: Flyx on 25 May 2010 04:48 Hi all, Having a [m x n] matrix A with m >> n and a vector b [m x 1] I am wondering why the results of the two following two operations is different: x1 = lscov(A,b); x2 = b\A; x1 differs from x2 Is there any explanation? Which one is the correct one for solving an overdetermined linear system Ax=b? Thanks --- news://freenews.netfront.net/ - complaints: news(a)netfront.net ---
From: Michael on 25 May 2010 05:04 Although I cannot help you on your actual problem, I want to throw in that the usage of lscov to me only seems necessary if you have a priori covariance information available. If you just want to solve an overdetermined equation system, "\" should be totally sufficient.
From: Flyx on 25 May 2010 05:27 "Michael " <michael.schmittNOSPAM(a)bv.tum.de> ha scritto nel messaggio news:htg3q5$j8k$1(a)fred.mathworks.com... > Although I cannot help you on your actual problem, I want to throw in that > the usage of lscov to me only seems necessary if you have a priori > covariance information available. If you just want to solve an > overdetermined equation system, "\" should be totally sufficient. Yes, I supposed. But lscov accepts even only the two parameters A and b given a result that completely matches to the "linsolve" one. Why does it differ from "\" ? It should be theoretically the same. Thanks --- news://freenews.netfront.net/ - complaints: news(a)netfront.net ---
From: Bruno Luong on 25 May 2010 05:55 "Flyx" <flyxylf(a)hotmail.com> wrote in message <htg2vb$16l$1(a)adenine.netfront.net>... > Hi all, > > Having a [m x n] matrix A with m >> n and a vector b [m x 1] > I am wondering why the results of the two following two operations is > different: > > x1 = lscov(A,b); > x2 = b\A; > Try x2 = A\b Bruno
From: Flyx on 25 May 2010 06:07
"Bruno Luong" <b.luong(a)fogale.findmycountry> ha scritto nel messaggio news:htg6ps$1sr$1(a)fred.mathworks.com... > "Flyx" <flyxylf(a)hotmail.com> wrote in message > <htg2vb$16l$1(a)adenine.netfront.net>... >> >> x1 = lscov(A,b); >> x2 = b\A; >> > Try > > x2 = A\b > > Bruno That is right! Thank you very much. --- news://freenews.netfront.net/ - complaints: news(a)netfront.net --- |