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Re: chol?
From: |
dastew |
Subject: |
Re: chol? |
Date: |
Sat, 15 Apr 2006 17:35:44 -0400 |
Here is what I get
GNU Octave, version 2.1.73 (i686-pc-cygwin).
Copyright (C) 2006 John W. Eaton.
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octave:1> C = [36 24; 24 25];
octave:2> C
C =
36 24
24 25
octave:3>
octave:3> chol(C)
ans =
6 4
0 3
Upper Triangular
Doug Stewart
>
> From: Vic Norton <address@hidden>
> Date: 2006/04/15 Sat PM 04:16:22 EST
> To: Octave Help <address@hidden>
> Subject: chol?
>
> I had thought Octave, version 2.1.73, was working fine on my iMac G5,
> but now I'm not so sure. Here's my problem.
>
> I start with the matrix
> octave> C = [36 24; 24 25];
> and do
> octave> chol(C);
> After waiting for a while I get
> panic: Bus error -- stopping myself...
> attempting to save variables to `octave-core'...
> save to `octave-core' complete
> Bus error
> vic$
>
> To tell you the truth I'm not sure what the Cholesky factor of C is
> supposed to be. I do know that C = R' * R where
> R = [0 3; 6 4].
> I have no problem computing another R that does this job:
> octave> C = [36 24; 24 25];
> octave> [U, S, V] = svd(C);
> octave> R = sqrt(S) * V';
> Now
> R = [
> -5.8067 -4.6265
> -1.5108 1.8962
> ]
> and C = R' * R for this R as well. But R = chol(C) simply doesn't work
> for me.
>
> Is anybody else having any problems with "chol" or is it just my screwed
> up system?
>
> Regards,
>
> Vic
>
>
>
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Octave is freely available under the terms of the GNU GPL.
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-------------------------------------------------------------
- chol?, Vic Norton, 2006/04/15
- Re: chol?, Jordi Gutierrez Hermoso, 2006/04/15
- Re: chol?,
dastew <=
Message not available
Re: chol?, Andy Pugh, 2006/04/16