Developer Reference for Intel® oneAPI Math Kernel Library for C

ID 766684
Date 12/16/2022
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents

cblas_?sdot

Computes a vector-vector dot product with double precision.

Syntax

float cblas_sdsdot (const MKL_INT n, const float sb, const float *sx, const MKL_INT incx, const float *sy, const MKL_INT incy);

double cblas_dsdot (const MKL_INT n, const float *sx, const MKL_INT incx, const float *sy, const MKL_INT incy);

Include Files
  • mkl.h
Description

The ?sdot routines compute the inner product of two vectors with double precision. Both routines use double precision accumulation of the intermediate results, but the sdsdot routine outputs the final result in single precision, whereas the dsdot routine outputs the double precision result. The function sdsdot also adds scalar value sb to the inner product.

Input Parameters
n

Specifies the number of elements in the input vectors sx and sy.

sb

Single precision scalar to be added to inner product (for the function sdsdot only).

sx, sy

Arrays, size at least (1+(n -1)*abs(incx)) and (1+(n-1)*abs(incy)), respectively. Contain the input single precision vectors.

incx

Specifies the increment for the elements of sx.

incy

Specifies the increment for the elements of sy.

Output Parameters
res

Contains the result of the dot product of sx and sy (with sb added for sdsdot), if n is positive. Otherwise, res contains sb for sdsdot and 0 for dsdot.

Return Values

The result of the dot product of sx and sy (with sb added for sdsdot), if n is positive. Otherwise, returns sb for sdsdot and 0 for dsdot.