Developer Reference

  • 0.9
  • 09/09/2020
  • Public Content
Contents

p?dot

Computes the dot product of two distributed real vectors.

Syntax

void psdot
(
const MKL_INT
*n
,
float
*dot
,
const float
*x
,
const MKL_INT
*ix
,
const MKL_INT
*jx
,
const MKL_INT
*descx
,
const MKL_INT
*incx
,
const float
*y
,
const MKL_INT
*iy
,
const MKL_INT
*jy
,
const MKL_INT
*descy
,
const MKL_INT
*incy
);
void pddot
(
const MKL_INT
*n
,
double
*dot
,
const double
*x
,
const MKL_INT
*ix
,
const MKL_INT
*jx
,
const MKL_INT
*descx
,
const MKL_INT
*incx
,
const double
*y
,
const MKL_INT
*iy
,
const MKL_INT
*jy
,
const MKL_INT
*descy
,
const MKL_INT
*incy
);
Include Files
  • mkl_pblas.h
Description
The
?dot
functions compute the dot product
dot
of two distributed real vectors defined as
dot = sub(x)'*sub(y)
where
sub(
x
)
and
sub(
y
)
are
n
-element distributed vectors.
sub(
x
)
denotes
X
(
ix
,
jx
:
jx
+
n
-1)
if
incx
=
m_x
, and
X
(
ix
:
ix
+
n
-1,
jx
)
if
incx
= 1
;
sub(
y
)
denotes
Y
(
iy
,
jy
:
jy
+
n
-1)
if
incy
=
m_y
, and
Y
(
iy
:
iy
+
n
-1,
jy
)
if
incy
= 1
.
Input Parameters
n
(global) The length of distributed vectors,
n
0.
x
(local)
Array, size
(
jx
-1)*
m_x
+
ix
+(
n
-1)*abs(
incx
))
.
This array contains the entries of the distributed vector
sub(
x
)
.
ix
,
jx
(global) The row and column indices in the distributed matrix
X
indicating the first row and the first column of the submatrix
sub(
X
)
, respectively.
descx
(global and local) array of dimension 9. The array descriptor of the distributed matrix
X
.
incx
(global) Specifies the increment for the elements of
sub(
x
)
. Only two values are supported, namely 1 and
m_x
.
incx
must not be zero.
y
(local)
Array, size
(
jy
-1)*
m_y
+
iy
+(
n
-1)*abs(
incy
))
.
This array contains the entries of the distributed vector
sub(
y
)
.
iy
,
jy
(global) The row and column indices in the distributed matrix
Y
indicating the first row and the first column of the submatrix
sub(
Y
)
, respectively.
descy
(global and local) array of dimension 9. The array descriptor of the distributed matrix
Y
.
incy
(global) Specifies the increment for the elements of
sub(
y
)
. Only two values are supported, namely 1 and
m_y
.
incy
must not be zero.
Output Parameters
dot
(local)
Dot product of
sub(
x
)
and
sub(
y
)
only in their scope.

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