[Gsll-devel] inverse-matrix-product

[Liam Healy]

On Wed, Feb 25, 2009 at 7:25 AM, Dmitri Hrapof <hrapof at common-lisp.ru> wrote:
> Hello!
>
> Just cloned git repository. In both SBCL 1.0.23 and ClozureCL
> 1.2-r11583M on Linux PPC, with GSL 1.9-3:
>
> CL-USER> (gsll:invert-matrix #m((1 0 2) (-1 3 1) (1 1 0)))
> #<MATRIX-DOUBLE-FLOAT #2A((0.11111111111111116D0 -0.2222222222222222D0
>                           0.6666666666666666D0)
>                          (-0.11111111111111109D0 0.22222222222222224D0
>                           0.3333333333333333D0)
>                          (0.4444444444444444D0 0.1111111111111111D0
>                           -0.3333333333333333D0))>
> CL-USER> (gsll:matrix-product * #m(3 2 1))
> #<VECTOR-DOUBLE-FLOAT #(0.5555555555555557D0 0.44444444444444453D0
>                        1.222222222222222D0)>
> CL-USER> (gsll:inverse-matrix-product #m((1 0 2) (-1 3 1) (1 1 0)) #m(3
> 2 1))
> #<VECTOR-DOUBLE-FLOAT #(1D+-0 #| not-a-number |# -1D++0 1D++0)>
>
> Do I misunderstand something?

No, I get a similar result.   I don't know why.  The macroexpansion to
the foreign function call looks right.
You don't by any chance have a C program calling GSL/BLAS that does
this calculation, do you?
That would help isolate whether the problem is in GSL or GSLL.

>
> Sincerely yours,
> Dmitri
>
> PS and to add insult to injury ;) nonsymmetric-generalized.lisp fails to
> compile, complaining about invalid function call: ("gsl_eigen_gen"
> "gsl_eigen_gen_QZ")
>
I've fixed and pushed this.  There was a bug in how it signaled
obsolete-gsl-version
(generalized eigensystem problems are not supported in GSL 1.9 so if you try to
call those functions it should give you an error).

Thanks for the report.

Liam