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[Lapack] BLAS question

Dear LAPACK folks,

We need to compute a matrix product of the form (hc=hermitian conjugate):

        H = hc(M)*Q, Q = h*M

where H and h are hermitian, Q is already computed (it's needed for
another stage).  As you can see we really need only the full upper
(or lower) triangle of the product matrix, H.  Looking through the
BLAS routines we have not found any special routine which would be faster
than the general matrix multiply of hc(M) and Q.  Is there some multiply
routine where we could specify only compute the full upper (or lower)
triangle of the product (so as to speed things up by a bit less than a
factor of 2)?

Tim Boykin


Timothy Boykin, Ph.D.   
Professor (*)
Department of Electrical & Computer Engineering
The University of Alabama in Hunstville
Huntsville, Alabama  35899

(*) effective Aug. 2007; presently "Associate Professor"...

email:  boykin@Domain.Removed

Voice:  (256) 824-6269
FAX:    (256) 824-6803  (9AM-5PM Central Time)
        (256) 824-3482  (5PM-9AM Central Time)
"You know, Foley, I have only one eye.  I have a right to be blind 
sometimes.  I really do not see the signal."

Vice-Admiral Lord Horatio Nelson (with telescope held to his bad eye) to 
Captain Foley (on board Nelson's flagship HMS Elephant at the Battle of 
Copenhagen, 2 April 1801) explaining why he is ignoring Admiral Sir Hyde 
Parker's signal to discontinue action.  Parker assumed that Nelson would
disregard the order if he (Nelson) could continue the attack and indeed
supported Nelson's squadron when he saw that Nelson was pressing forward.

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