Weighted dot product

 

SWDOT/DWDOT/CWDOTC/CWDOTU/ZWDOTC/ZWDOTU

Input

n

Number of elements of vectors w, x, and y to be used in

 

 

the dot product. If n ≤ 0, the subprograms do not

 

 

reference w, x, or y.

 

w

Array of length lenw = (n−1)⋅incw+1 containing the

 

 

n-vector w.

 

 

incw

Increment for the array w:

 

 

incw ≥ 0

w is stored forward in array w; that is,

 

 

 

wi is stored in w((i−1)⋅incw+1).

 

 

incw < 0

w is stored backward in array w; that

 

 

 

is, wi is stored in w((i−n)⋅incw+1).

 

 

Use incw = 1 if the vector w is stored contiguously in

 

 

array w; that is, if wi is stored in w(i). Refer to “BLAS

 

 

Indexing Conventions” in the introduction to this

 

 

chapter.

 

 

x

Array of length lenx = (n−1)⋅incx+1 containing the

 

 

n-vector x. x is used in conjugated form by CWDOTC

 

 

and ZWDOTC and in unconjugated form by the other

 

 

subprograms.

 

 

incx

Increment for the array x:

 

 

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 this

 

 

chapter.

 

 

y

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

 

 

n-vector y.

 

Chapter 2 Basic Vector Operations 147