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Notes for AXPBY

  1. Performs $ y \leftarrow \alpha x + \beta y $
  2. An index file input line looks like:
    <ID> <alpha> <beta> <incX> <incY> <source file> <author name>
    

  3. The kernel will never be called with beta == 1.0 (AXPY is called instead).
  4. The kernel will never be called with beta == 0.0 (CPSC is called instead).
  5. The kernel will never be called with alpha == 0.0 (SCAL is called instead).
  6. For complex, if both vector strides are 1, and the imaginary components of alpha and beta are both zero, the real kernel is called with 2*N.



R. Clint Whaley 2001-08-04