Re: [Help-gsl] matrix multiplication

[Paulo Jabardo]

There are two interfaces to multiply the matrices. The
The one you are attempting to use is the low level
cblas interface. In this case you should use something
like

cblas_dgemm(
        CblasRowMajor,
        CblasNoTrans,
        CblasNoTrans,
        n, l, n, 1.0, A->data, A->tda, B->data,
B->tda, 0.0, AB->data, AB->tda);


This function is defined in gsl_cblas.h.

Since you are using gsl_matrix matrices, gsl has
wrappers that operate on gsl_matrix objetcs (defined
on gsl_blas.h:

gsl_blas_dgemm(
        CblasNoTrans,
        CblasNoTrans,
        1.0, A, B, 0.0, C)

I recommend you use that.


Hope this helps

Paulo

--- Keymone <address@hidden> escreveu:

> hello guys
> 
> help me please to multiplicate 2 matrices :)
> 
> gsl_matrix * A = gsl_matrix_alloc(n, n);
> gsl_matrix * B = gsl_matrix_alloc(n, l);
> gsl_matrix * AB = gsl_matrix_alloc(n, l);
> 
> cblas_dgemm(
>         CblasRowMajor,
>         CblasNoTrans,
>         CblasNoTrans,
>         ?, ?, ?, 1.0, ?, ?, ?, ?, 0, ?, ?);
> 
> it looks like primitive operation but i can't figure
> this out
> i started with GSL only tomorrow so don't kill me :)
> 
> -- 
> Regards, Keymone
> _______________________________________________
> Help-gsl mailing list
> address@hidden
> http://lists.gnu.org/mailman/listinfo/help-gsl
> 


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