[Help-gsl] Re: General CBLAS question

[Rodney Sparapani]

On 09/ 9/10 03:01 PM, Rodney Sparapani wrote:
> I looked for this in the GSL docs, but maybe it is too basic.
> I also looked at the source, but I must be missing something.
> Anyways, many CBLAS functions calculate something like
> y = a A x + b y. I need (and have tried) the following which
> seems to work: y = 1 A y + 0 y. Is that OK or will you run
> into trouble somehow. Any pointers welcome. Thanks
>
> Rodney

Oh, and getting back to the original question.  Am I reading the
BLAST Forum standard correctly in stating that the correctness of
y = 1 A y + 0 y is not guaranteed?  On page 26, in subsection 2.3.2,
it states:  Correctness is only guaranteed if output arguments are not
aliased with any other arguments.  The fact that y is both the
first and second vector passed to dgemv would imply an alias
between the arguments, correct?

By the way, there must be an Errata somewhere since on that page in
the above subsection 2.2.6, there are some obvious typos such as
x(i)).

Rodney