Visible to Intel only — GUID: GUID-FEB11238-3B0F-4770-B00C-F237CDDFAEAC
Visible to Intel only — GUID: GUID-FEB11238-3B0F-4770-B00C-F237CDDFAEAC
p?latra
Computes the trace of a general square distributed matrix.
Syntax
val = pslatra(n, a, ia, ja, desca)
val = pdlatra(n, a, ia, ja, desca)
val = pclatra(n, a, ia, ja, desca)
val = pzlatra(n, a, ia, ja, desca)
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) INTEGER.
The number of rows and columns to be operated on, that is, the order of the distributed matrix sub(A). n ≥0.
- a
-
(local).
REAL for pslatra
DOUBLE PRECISION for pdlatra
COMPLEX for pclatra
COMPLEX*16 for pzlatra.
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) INTEGER. 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) INTEGER array of size dlen_. The array descriptor for the distributed matrix A.
Output Parameters
- val
-
The value returned by the function.