Developer Reference for Intel® oneAPI Math Kernel Library - C

Developer Reference

Contents

p?latra

Computes the trace of a general square distributed matrix.

Syntax

float
pslatra
(
MKL_INT
*n
,
float
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
);
double
pdlatra
(
MKL_INT
*n
,
double
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
);
void
pclatra
(
MKL_Complex8
*
,
MKL_INT
*n
,
MKL_Complex8
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
);
void
pzlatra
(
MKL_Complex16
*
,
MKL_INT
*n
,
MKL_Complex16
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
);
Include Files
  • mkl_scalapack.h
Description
This function computes the trace of an
n
-by-
n
 distributed matrix sub(
A
) denoting
A
(
ia
:
ia
+
n
-1
,
ja
:
ja
+
n
-1)
. The result is left on every process of the grid.
Input Parameters
n
(global)
The number of rows and columns to be operated on, that is, the order of the distributed matrix sub(
A
).
n
≥
0
.
a
(local).
Pointer into the local memory to an array of size
lld_a
 *
LOCc
(
ja
+
n
-1)
 containing the local pieces of the distributed matrix, the trace of which is to be computed.
ia
,
ja
(global) The row and column indices respectively in the global matrix
A
 indicating the first row and the first column of the matrix sub(
A
), respectively.
desca
(global and local) array of size
dlen_
. The array descriptor for the distributed matrix
A
.
Output Parameters
val
The value returned by the function.

Product and Performance Information

1

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