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Re: funny behavior of the sparse
From: |
David Bateman |
Subject: |
Re: funny behavior of the sparse |
Date: |
Wed, 22 Nov 2006 12:40:06 +0100 |
User-agent: |
Thunderbird 1.5.0.7 (X11/20060921) |
Yes this is strange, particularly as
spinv(A')'
given a correct result, and internally this is pretty much what is down
with this case... I'll take a look, but can say when I'll get back with
an answer..
D.
Gorazd Brumen wrote:
> Hi,
>
> A = sparse ([1:10, 10], [1:10,5], [1:10 1], 10,10)
> A =
>
> Compressed Column Sparse (rows = 10, cols = 10, nnz = 11)
>
> (1, 1) -> 1
> (2, 2) -> 2
> (3, 3) -> 3
> (4, 4) -> 4
> (5, 5) -> 5
> (10, 5) -> 1
> (6, 6) -> 6
> (7, 7) -> 7
> (8, 8) -> 8
> (9, 9) -> 9
> (10, 10) -> 10
>
> octave:5> spinv (A)
> error: division by zero
> warning: spinverse: matrix singular to machine precision, rcond = 0
>
>
> This does not make much sense?
> Tested on Octave 2.9.9 and 2.9.7
>
> Regards,
> Gorazd
>
>
>
>
>
--
David Bateman address@hidden
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