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Re: matrix multiplication
- From: Brian Gough <bjg at network-theory dot co dot uk>
- To: Daniel T Konkle <daniel dot konkle at dynetics dot com>
- Cc: gsl-discuss at sources dot redhat dot com
- Date: Wed, 24 Jul 2002 19:14:13 +0100 (BST)
- Subject: Re: matrix multiplication
- References: <5.1.1.5.2.20020722103713.032d8f40@mailhub.dynetics.com>
Daniel T Konkle writes:
> I need to implement S = A' * A where A' is the transpose of A.
> Is it possible to do it like this:
> gsl_blas_dgemm( CblasTrans, CblasNoTrans, 1.0, A, A, 0.0, S );
> or do I need to copy the contents of a into a temporary matrix
> first
> gsl_matrix_memcpy( B, A ); gsl_blas_dgemm( CblasTrans,
> CblasNoTrans, 1.0, A, B, 0.0, S );
If you look at the function definition in the gsl_blas.h header file
or the manual the 'const' keyword shows which arguments are not
modified.
regards
Brian Gough