Questions about Blas

Barry Smith bsmith at
Wed Sep 16 09:54:49 CDT 2009

    Since you are using a fill factor of 2, I assume that you are  
multiplying sparse matrices? In this case the BLAS are not used since  
they are only for dense matrix computations.

    If you use Emacs take a look at the Emacs Users section in the  
users manual. It will tell you a simple way to find all the  
MatMatMult_*** functions. Essentially in Emacs just use
esc . MatMatMult_ then esc 0 esc . to find the next use.


On Sep 16, 2009, at 10:38 AM, Rodrigo Araujo wrote:

> Hi All,
> I am multiplying matrices using this line of code:
> ierr = MatMatMult(A, B, MAT_INITIAL_MATRIX, ((PetscReal) 2.0),  
> &C);CHKERRQ(ierr);
> But I need to see the source code of the file which has this  
> function, because I´d want to see how the functions from BLAS is  
> being used. Is that possible? If yes, could somebody tell me how.
> Thaks very much,
> Regards.
> -- 
> Rodrigo W. Pimentel Araujo
> Engenharia da Computação

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