Intel® oneAPI Math Kernel Library Developer Reference - Fortran
Computes the trace of a general square distributed matrix.
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)
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.
(global) INTEGER.
The number of rows and columns to be operated on, that is, the order of the distributed matrix sub(A). n ≥0.
(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.
(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.
(global and local) INTEGER array of size dlen_. The array descriptor for the distributed matrix A.
The value returned by the function.