Karim Belabas on Thu, 29 Oct 2015 11:21:07 +0100


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Re: qfgaussred() for singular matrices


* Bill Allombert [2015-10-29 11:03]:
> On Wed, Oct 28, 2015 at 12:22:18PM +0100, Jeroen Demeyer wrote:
> > Hello,
> > 
> > it is not clear to me if qfgaussred() is officially supported for
> > singular matrices.

It is. I'm changing the documentation to make it more explicit.

> > I am asking because of this unexpected output:
> > 
> > gp> qfgaussred([1,1;1,1])
> > %1 =
> > [1 1]
> > 
> > [1 0]
> > 
> > The problem is that the new basis vectors are (1,1) and (1,1) which
> > are not linearly independent.
> 
> Note that this does not seem to contradict the documentation.

Indeed.

Cheers,

    K.B.
--
Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
Universite de Bordeaux         Fax: (+33) (0)5 40 00 69 50
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