Developer Reference for Intel® oneAPI Math Kernel Library for Fortran

ID 766686
Date 7/13/2023
Public

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p?laevswp

Moves the eigenvectors from where they are computed to ScaLAPACK standard block cyclic array.

Syntax

call pslaevswp(n, zin, ldzi, z, iz, jz, descz, nvs, key, rwork, lrwork)

call pdlaevswp(n, zin, ldzi, z, iz, jz, descz, nvs, key, rwork, lrwork)

call pclaevswp(n, zin, ldzi, z, iz, jz, descz, nvs, key, rwork, lrwork)

call pzlaevswp(n, zin, ldzi, z, iz, jz, descz, nvs, key, rwork, lrwork)

Description

The p?laevswproutine moves the eigenvectors (potentially unsorted) from where they are computed, to a ScaLAPACK standard block cyclic array, sorted so that the corresponding eigenvalues are sorted.

Input Parameters

np = the number of rows local to a given process.

nq = the number of columns local to a given process.

n

(global) INTEGER.

The order of the matrix A. n 0.

zin

(local).

REAL for pslaevswp

DOUBLE PRECISION for pdlaevswp

COMPLEX for pclaevswp

COMPLEX*16 for pzlaevswp.

Array of size (ldzi, nvs(iam+2) ). The eigenvectors on input. iam is a process rank from [0, nprocs) interval. Each eigenvector resides entirely in one process. Each process holds a contiguous set of nvs(iam+2) eigenvectors. The global number of the first eigenvector that the process holds is: ((sum for i=[1, iam+1] of nvs(i))+1).

ldzi

(local)

INTEGER. The leading dimension of the zin array.

iz, jz

(global) INTEGER. The row and column indices in the global matrix Z indicating the first row and the first column of the submatrix Z, respectively.

descz

(global and local) INTEGER

Array of size dlen_. The array descriptor for the distributed matrix Z.

nvs

(global) INTEGER.

Array of size nprocs+1

nvs(i) = number of eigenvectors held by processes [0, i-1)

nvs(1) = number of eigenvectors held by processes [0, 1 -1) = 0

nvs(nprocs+1)= number of eigenvectors held by processes [0, nprocs)= total number of eigenvectors.

key

(global) INTEGER.

Array of size n. Indicates the actual index (after sorting) for each of the eigenvectors.

rwork

(local).

REAL for pslaevswp

DOUBLE PRECISION for pdlaevswp

COMPLEX for pclaevswp

COMPLEX*16 for pzlaevswp.

Array of size lrwork.

lrwork

(local)

INTEGER. Size of work.

Output Parameters

z

(local).

REAL for pslaevswp

DOUBLE PRECISION for pdlaevswp

COMPLEX for pclaevswp

COMPLEX*16 for pzlaevswp.

Array of global size nby n and of local size (lld_z, nq). The eigenvectors on output. The eigenvectors are distributed in a block cyclic manner in both dimensions, with a block size of nb.

See Also