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Date: Mon, 3 May 2010 08:39:54 +0000 (GMT)
From: texsit <texsit AT yahoo DOT it>
Subject: Octave 3.2.3: wrong matrix calculation
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Hi All,
I use octave 3.2.3 under Cygwin (windows 7) for my math application.=20
I discovered a bad calculation calling the function det(). The step to repr=
oduce is this:

> A =3D [1,2,3;4,5,6;7,8,9];
> det(A)
ans =3D -9.5171e-16

The matrix is singular so I expected the resul was 0 and not a very very li=
ttle number. I problem is the same also with Octave 3.2.4.
At the begin I thougth it was only a round error, but I've made the same pr=
oof with Octave under Debian Linux (lenny).=20
Under Linux=A0the resul has been 0 as I expected.

Can anyone suggest me something to solve that problem?

I'm using Cygwin 1.7.5-1 with Intel centrino 2 and windows 7 64 bit.

Thank you in advance.
Regards.

Luca




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