From: Jason Riedy
Date: Thu, 10 Jul 2014 15:06:19 -0400
And James Demmel writes:
How to do this of course depends on how we decide to treat the cases
Behavior here is fixed by decades of code depending on current behavior. I
know I've used beta=0 to multiply into uninitialized memory. GEMM documents
that case specifically. I have a sneaking suspicion people have used alpha=0
to scale or initialize C (likely some submatrix of a larger matrix).