SSYMV/DSYMV/CHEMV/ZHEMV

Matrix-vector multiply

incx

Increment for the array x, incx ≠ 0:

 

incx > 0

x is stored forward in array x; that is,

 

 

xi is stored in x((i−1)⋅incx+1).

 

incx < 0

x is stored backward in array x; that

 

 

is, xi is stored in x((i−n)⋅incx+1).

 

Use incx = 1 if the vector x is stored contiguously in

 

array x, that is, if xi is stored in x(i). Refer to “BLAS

 

Indexing Conventions” in the introduction to

 

Chapter 2.

 

beta

The scalar β.

 

y

Array of length leny = (n−1)⋅incy+1 containing the

 

n-vector y. Not used as input if beta = 0.

272HP MLIB User’s Guide