Developer Reference for Intel® oneAPI Math Kernel Library - C

Developer Reference

  • 0.9
  • 09/09/2020
  • Public Content
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
.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804