[Pkg-octave-devel] Bug#525113: Bug#525113: Bug#525113: Inconsistant complex matrix multiplication

[Laurent Mazet <mazet@softndesign.org>]

Hi Thomas,

you was right, my problem is inthe atlas library:

$ LD_LIBRARY_PATH=/usr/lib /usr/bin/octave -q --eval '[1 2; 3 4] * [1; 1i]'
ans =
   1 + 2i
   3 + 4i

$ lmt-linux ~ $ /usr/bin/octave -q --eval '[1 2; 3 4] * [1; 1i]'
ans =
   1.0000 + 0.0000i
   3.0000 + 0.0000i

$ ldd /usr/bin/octave | grep -i lapack
	liblapack.so.3gf => /usr/lib/sse2/atlas/liblapack.so.3gf (0xb653f000)
$ dpkg -S /usr/lib/sse2/atlas/liblapack.so.3gf
libatlas3gf-sse2: /usr/lib/sse2/atlas/liblapack.so.3gf
$ dpkg -l libatlas3gf-sse2
...
+++-==============-==============-============================================
ii  libatlas3gf-ss 3.6.0-24       Automatically Tuned Linear Algebra Software,

Does I need to make a follow-up to the atlas package bug-report system?

Regards,

     Laurent

Quoting Thomas Weber <thomas.weber.mail@gmail.com>:

> On Wed, Apr 22, 2009 at 11:04:14PM +0200, Thomas Weber wrote:
> > On Wed, Apr 22, 2009 at 12:01:19PM +0200, Laurent Mazet wrote:
> > > Package: octave3.0
> > > Version: 1:3.0.1-7
> > > Arch: i386
> > > Severity: grave
> > >
> > > Hi,
> > >
> > > I've just realized that I can multiply a real 2x2 matrix by a  
> > complex vector.
> >
> > Uh, yes. Why shouldn't this work? Or in other words, how do you
> > distinguish the real matrix from a complex matrix with its complex
> > coefficients being zero
> >
> > [ 1, 2; 3,4] is the same as [1+0i, 2+0i; 3+0i, 4+0i], isn't it?
>
> Sorry, I just realized that the problem was the result, not the act of
> multiplication. Anyway, which BLAS/ATLAS libraries are installed on your
> system?
>
> 	Thomas



--
Dr. Laurent Mazet   -=-  "Use the source, Luke"  -=-   mazet@softndesign.org