Developer Reference

  • 098
  • 03/30/2020
  • Public Content
Contents

p?ger

Performs a rank-1 update of a distributed general matrix.

Syntax

call psger
(
m
,
n
,
alpha
,
x
,
ix
,
jx
,
descx
,
incx
,
y
,
iy
,
jy
,
descy
,
incy
,
a
,
ia
,
ja
,
desca
)
call pdger
(
m
,
n
,
alpha
,
x
,
ix
,
jx
,
descx
,
incx
,
y
,
iy
,
jy
,
descy
,
incy
,
a
,
ia
,
ja
,
desca
)
Include Files
  • mkl_pblas.h
Description
The
p?ger
routines perform a distributed matrix-vector operation defined as
sub(
A
) :=
alpha
*sub(
x
)*sub(
y
)' + sub(
A
),
where:
alpha
is a scalar,
sub(
A
) is a
m
-by-
n
distributed general matrix,
sub(
A
)=
A
(
ia
:
ia
+
m
-1,
ja
:
ja
+
n
-1)
,
sub(
x
)
is an
m
-element distributed vector, sub(
y
) is an
n
-element distributed vector,
sub(
x
)
denotes
X
(
ix
,
jx
:
jx
+
m
-1)
if
incx
=
m_x
, and
X
(
ix
:
ix
+
m
-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
m
(global)
INTEGER
.
Specifies the number of rows of the distributed matrix
sub(
A
)
,
m
0.
n
(global)
INTEGER
.
Specifies the number of columns of the distributed matrix
sub(
A
)
,
n
0.
alpha
(global)
REAL
for
psger
DOUBLE REAL
for
pdger
Specifies the scalar
alpha
.
x
(local)
REAL
for
psger
DOUBLE REAL
for
pdger
Array, size at least
(
jx
-1)*
m_x
+
ix
+(
m
-1)*abs(
incx
))
.
This array contains the entries of the distributed vector
sub(
x
)
.
ix
,
jx
(global)
INTEGER
.
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)
INTEGER
array of dimension 9. The array descriptor of the distributed matrix
X
.
incx
(global)
INTEGER
.
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)
REAL
for
psger
DOUBLE REAL
for
pdger
Array, size at least
(
jy
-1)*
m_y
+
iy
+(
n
-1)*abs(
incy
))
.
This array contains the entries of the distributed vector
sub(
y
)
.
iy
,
jy
(global)
INTEGER
.
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)
INTEGER
array of dimension 9. The array descriptor of the distributed matrix
Y
.
incy
(global)
INTEGER
.
Specifies the increment for the elements of
sub(
y
)
. Only two values are supported, namely 1 and
m_y
.
incy
must not be zero.
a
(local)
REAL
for
psger
DOUBLE REAL
for
pdger
Array, size
(
lld_a
, LOCq(
ja
+
n
-1))
.
Before entry this array contains the local pieces of the distributed matrix
sub(
A
)
.
ia
,