Developer Reference

Contents

p?lase2

Initializes an
m
-by-
n
distributed matrix.

Syntax

void pslase2
(
const
char*
uplo
,
const
MKL_INT*
m
,
const
MKL_INT*
n
,
const
float*
alpha
,
const
float*
beta
,
float*
a
,
const
MKL_INT*
ia
,
const
MKL_INT*
ja
,
const
MKL_INT*
desca
);
void pdlase2
(
const
char*
uplo
,
const
MKL_INT*
m
,
const
MKL_INT*
n
,
const
double*
alpha
,
const
double*
beta
,
double*
a
,
const
MKL_INT*
ia
,
const
MKL_INT*
ja
,
const
MKL_INT*
desca
);
void pclase2
(
const
char*
uplo
,
const
MKL_INT*
m
,
const
MKL_INT*
n
,
const
MKL_Complex8*
alpha
,
const
MKL_Complex8*
beta
,
MKL_Complex8*
a
,
const
MKL_INT*
ia
,
const
MKL_INT*
ja
,
const
MKL_INT*
desca
);
void pzlase2
(
const
char*
uplo
,
const
MKL_INT*
m
,
const
MKL_INT*
n
,
const
MKL_Complex16*
alpha
,
const
MKL_Complex16*
beta
,
MKL_Complex16*
a
,
const
MKL_INT*
ia
,
const
MKL_INT*
ja
,
const
MKL_INT*
desca
);
Include Files
  • mkl_scalapack.h
Description
p?lase2
initializes an
m
-by-
n
distributed matrix sub(
A
) denoting
A
(
ia
:
ia
+
m
-1,
ja
:
ja
+
n
-1) to
beta
on the diagonal and
alpha
on the off-diagonals.
p?lase2
requires that only the dimension of the matrix operand is distributed.
Input Parameters
uplo
(global)
Specifies the part of the distributed matrix sub(
A
) to be set:
= 'U': Upper triangular part is set; the strictly lower triangular part of sub(
A
) is not changed;
= 'L': Lower triangular part is set; the strictly upper triangular part of sub(
A
) is not changed;
Otherwise: All of the matrix sub(
A
) is set.
m
(global)
The number of rows to be operated on i.e the number of rows of the distributed submatrix sub(
A
).
m
>= 0.
n
(global)
The number of columns to be operated on i.e the number of columns of the distributed submatrix sub(
A
).
n
>= 0.
alpha
(global)
The constant to which the off-diagonal elements are to be set.
beta
(global)
The constant to which the diagonal elements are to be set.
ia
(global)
The row index in the global array
a
indicating the first row of sub(
A
).
ja
(global)
The column index in the global array
a
indicating the first column of sub(
A
).
desca
(global and local)
Array of size
dlen_
.
The array descriptor for the distributed matrix
A
.
Output Parameters
a
(local)
Pointer into the local memory to an array of size
lld_a
*
LOCc
(
ja
+
n
-1)
.
This array contains the local pieces of the distributed matrix sub(
A
) to be set.
On exit, the leading
m
-by-
n
submatrix sub(
A
) is set as follows:
if
uplo
= 'U',
A
(
ia
+i-1,
ja
+j-1) =
alpha
,
1<=i<=j-1, 1<=j<=
n
,
if
uplo
= 'L',
A
(
ia
+i-1,
ja
+j-1) =
alpha
,
j+1<=i<=
m
, 1<=j<=
n
,
otherwise,
A
(
ia
+i-1,
ja
+j-1) =
alpha
, 1<=i<=
m
,
1<=j<=
n
,
ia
+i !=
ja
+j,
and, for all
uplo
,
A
(
ia
+i-1,
ja
+i-1) =
beta
,
1<=i<=min(
m
,
n
)
.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.