Developer Reference

  • 2020.2
  • 07/15/2020
  • Public Content
Contents

p?rscl

Multiplies a vector by the reciprocal of a real scalar.

Syntax

call psrscl
(
n
,
sa
,
sx
,
ix
,
jx
,
descx
,
incx
)
call pdrscl
(
n
,
sa
,
sx
,
ix
,
jx
,
descx
,
incx
)
call pcsrscl
(
n
,
sa
,
sx
,
ix
,
jx
,
descx
,
incx
)
call pzdrscl
(
n
,
sa
,
sx
,
ix
,
jx
,
descx
,
incx
)
Description
The
p?rscl
routine
multiplies an
n
-element real/complex vector sub(
X
) by the real scalar 1/
a
. This is done without overflow or underflow as long as the final result sub(
X
)/a does not overflow or underflow.
sub(
X
) denotes
X
(
ix
:
ix
+
n
-1,
jx
:
jx
)
, if
incx
= 1
,
and
X
(
ix
:
ix
,
jx
:
jx
+
n
-1)
, if
incx
=
m_x
.
Input Parameters
n
(global)
INTEGER
.
The number of components of the distributed vector sub(
X
).
n
0
.
sa
REAL
for
psrscl/pcsrscl
DOUBLE PRECISION
for
pdrscl/pzdrscl
.
The scalar
a
that is used to divide each component of the vector sub(
X
). This parameter must be
0.
sx
REAL
for
psrscl
DOUBLE PRECISION
for
pdrscl
COMPLEX
for
pcsrscl
COMPLEX*16
for
pzdrscl
.
Array containing the local pieces of a distributed matrix of size of at least
((
jx
-1)*
m_x
+
ix
+ (
n
-1)*abs(
incx
))
. This array contains the entries of the distributed vector sub(
X
).
ix
(global)
INTEGER
.
The row index of the submatrix of the distributed matrix
X
to operate on.
jx
(global)
INTEGER
.
The column index of the submatrix of the distributed matrix
X
to operate on.
descx
(global and local)
INTEGER
.
Array of size 9. The array descriptor for the distributed matrix
X
.
incx
(global)
INTEGER
.
The increment for the elements of
X
. This version supports only two values of
incx
, namely 1 and
m_x
.
Output Parameters
sx
On exit, the result
x
/
a
.

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