Developer Reference

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

?gem2vu

Computes two matrix-vector products using a general matrix (real data)

Syntax

call sgem2vu
(
m
,
n
,
alpha
,
a
,
lda
,
x1
,
incx1
,
x2
,
incx2
,
beta
,
y1
,
incy1
,
y2
,
incy2
)
call dgem2vu
(
m
,
n
,
alpha
,
a
,
lda
,
x1
,
incx1
,
x2
,
incx2
,
beta
,
y1
,
incy1
,
y2
,
incy2
)
call gem2vu
(
a
,
x1
,
x2
,
y1
,
y2
[
,
alpha
]
[
,
beta
]
)
Include Files
  • mkl.fi
    ,
    blas.f90
Description
The
?gem2vu
routines perform two matrix-vector operations defined as
y1
:=
alpha
*
A
*
x1
+
beta
*
y1
,
and
y2
:=
alpha
*
A
'*
x2
+
beta
*
y2
,
where:
alpha
and
beta
are scalars,
x1
,
x2
,
y1
, and
y2
are vectors,
A
is an
m
-by-
n
matrix.
Input Parameters
m
INTEGER
.
Specifies the number of rows of the matrix
A
. The value of
m
must be at least zero.
n
INTEGER
.
Specifies the number of columns of the matrix
A
. The value of
n
must be at least zero.
alpha
REAL
for
sgem2vu
DOUBLE PRECISION
for
dgem2vu
Specifies the scalar
alpha
.
a
REAL
for
sgem2vu
DOUBLE PRECISION
for
dgem2vu
Array, size
(
lda
,
n
)
. Before entry, the leading
m
-by-
n
part of the array
a
must contain the matrix of coefficients.
lda
INTEGER
.
Specifies the leading dimension of
a
as declared in the calling (sub)program. The value of
lda
must be at least
max(1,
m
)
.
x1
REAL
for
sgem2vu
DOUBLE PRECISION
for
dgem2vu
Array, size at least
(1+(
n
-1)*abs(
incx1
))
. Before entry, the incremented array
x1
must contain the vector
x1
.
incx1
INTEGER
.
Specifies the increment for the elements of
x1
.
The value of
incx1
must not be zero.
x2
REAL
for
sgem2vu
DOUBLE PRECISION
for
dgem2vu
Array, size at least
(1+(
m
-1)*abs(
incx2
))
. Before entry, the incremented array
x2
must contain the vector
x2
.
incx2
INTEGER
.
Specifies the increment for the elements of
x2
.
The value of
incx2
must not be zero.
beta
REAL
for
sgem2vu
DOUBLE PRECISION
for
dgem2vu
Specifies the scalar
beta
. When
beta
is set to zero, then
y1
and
y2
need not be set on input.
y1
REAL
for