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Re: Inverse Matrix Function appears a bit wonky
From: |
Robert A. Macy |
Subject: |
Re: Inverse Matrix Function appears a bit wonky |
Date: |
Wed, 03 Nov 2004 21:39:44 -0800 |
That's it! simply asking to return the value of rcond
allows me to catch a "bad" matrix.
Thank you.
- Robert -
On Wed, 03 Nov 2004 14:08:34 -0700
"Dmitri A. Sergatskov" <address@hidden> wrote:
> Robert A. Macy wrote:
> > I tried a simple test of the inverse function using a
> "made
> > up" matrix...
> >
> > testmatrix =
> > 1 2 3 4
> > 2 2 3 3
> > 1 2 1 2
> > 3 2 2 1
>
> Your matrix is no good. Set testmatrix(4,4)=-1 and try
> again :)
>
> > What do I do to make certain octave doesn't do these
> > erroneous inverse calculations the next time I go to
> use
> > the inverse function?
> >
>
> Instead of b=inv(a), you can try [b,r]=inv(a), and check
> that r is not too small.
>
> > - Robert -
>
> Cheers,
>
> Dmitri.
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- Inverse Matrix Function appears a bit wonky, (continued)
- Re: Inverse Matrix Function appears a bit wonky, Dmitri A. Sergatskov, 2004/11/03
- Re: Inverse Matrix Function appears a bit wonky,
Robert A. Macy <=
- Re: Inverse Matrix Function appears a bit wonky, David Bateman, 2004/11/04
- Re: Inverse Matrix Function appears a bit wonky, John W. Eaton, 2004/11/04
- Re: Inverse Matrix Function appears a bit wonky, David Bateman, 2004/11/05
- Re: Inverse Matrix Function appears a bit wonky, John W. Eaton, 2004/11/05
- Re: Inverse Matrix Function appears a bit wonky, David Bateman, 2004/11/05
Re: Inverse Matrix Function appears a bit wonky, Geraint Paul Bevan, 2004/11/03