Re: don't understand inverseimage

[Ramón Casero Cañas <rcasero@tsc.uc3m.es>]

Bill Allombert wrote:
> On Tue, Dec 17, 2002 at 11:10:42PM +0100, rcasero@tsc.uc3m.es wrote:

> matinverseimage(A,Y) return a solution of AX=Y if it exists, and [;] else.

Um, I have another question linked to Bill's answer. Let's say the 
matrix is invertible. Each time that a vector's inverse image is to be 
computed, the matrix has to be inverted (or whichever process it 
follows), isn't it? That doesn't seem efficient from a computational 
point of view (and I'm not saying that that function was written with 
that idea, or maybe it's more efficient that way than inverting the 
matrix and then use the inverse as a linear mapping, I don't know). I've 
been reading other functions descriptions, and I haven't found anything 
like "inverse(A)".


Regards,

Ramón.

--
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                Ramón Casero Cañas
                rcasero@tsc.uc3m.es

              Ing. de Telecomunicación.
          Universidad Carlos III de Madrid
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