## Developer Reference

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

# p?rot

Applies a planar rotation to two distributed vectors.

## Syntax

Description
p?rot
applies a planar rotation defined by
cs
and
sn
to the two distributed vectors sub(
x
) and sub(
y
).
Input Parameters
n
(global )
INTEGER
The number of elements to operate on when applying the planar rotation to
x
and
y
(
n
0).
x
REAL
for
psrot
DOUBLE PRECISION
for
pdrot
(local) array of size ( (
jx
-1)*
m_x
+
ix
+ (
n
- 1 )*abs(
incx
) )
This array contains the entries of the distributed vector sub(
x
).
ix
(global )
INTEGER
The global row index of the submatrix of the distributed matrix
x
to operate on. If
incx
= 1, then it is required that
ix
=
iy
. 1
ix
m_x
.
jx
(global )
INTEGER
The global column index of the submatrix of the distributed matrix
x
to operate on. If
incx
=
m_x
, then it is required that
jx
=
jy
. 1
ix
n_x
.
descx
(global and local)
INTEGER
array of size 9
The array descriptor of the distributed matrix
x
.
incx
(global )
INTEGER
The global increment for the elements of
x
. Only two values of
incx
are supported in this version, namely 1 and
m_x
. Moreover, it must hold that
incx
=
m_x
if
incy
=
m_y
and that
incx
= 1 if
incy
= 1.
y
REAL
for
psrot
DOUBLE PRECISION
for
pdrot
(local) array of size ( (
jy
-1)*
m_y
+
iy
+ (
n
- 1 )*abs(
incy
) )
This array contains the entries of the distributed vector sub(
y
).
iy
(global )
INTEGER
The global row index of the submatrix of the distributed matrix
y
to operate on. If
incy
= 1, then it is required that
iy
=
ix
. 1
iy
m_y
.
jy
(global )
INTEGER
The global column index of the submatrix of the distributed matrix
y
to operate on. If
incy
=
m_x
, then it is required that
jy
=
jx
. 1
jy
m_y
.
descy
(global and local)
INTEGER
array of size 9
The array descriptor of the distributed matrix
y
.
incy
(global )
INTEGER
The global increment for the elements of
y
. Only two values of
incy
are supported in this version, namely 1 and
m_y
. Moreover, it must hold that
incy
=
m_y
if
incx
=
m_x
and that
incy
= 1 if
incx
= 1.
cs
,
sn
(global)
REAL
for
psrot
DOUBLE PRECISION
for
pdrot
The parame