Developer Reference for Intel® oneAPI Math Kernel Library for Fortran

ID 766686
Date 3/31/2023
Public

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p?lasrt

Sorts the numbers in an array and the corresponding vectors in increasing order.

Syntax

call pslasrt (id, n, d, q, iq, jq, descq, work, lwork, iwork, liwork, info )

call pdlasrt (id, n, d, q, iq, jq, descq, work, lwork, iwork, liwork, info )

Description

p?lasrt sorts the numbers in d and the corresponding vectors in q in increasing order.

Input Parameters
id

(global)

CHARACTER*1.

= 'I': sort d in increasing order;

= 'D': sort d in decreasing order. (NOT IMPLEMENTED YET)

n

(global)

INTEGER.

The number of columns to be operated on i.e the number of columns of the distributed submatrix sub( Q ). n >= 0.

d

(global)

REAL for pslasrt

DOUBLE PRECISION for pdlasrt

Array, size (n)

q

(local)

REAL for pslasrt

DOUBLE PRECISION for pdlasrt

Pointer into the local memory to an array of size (lld_q,LOCc(jq+n-1)) .

This array contains the local pieces of the distributed matrix sub( A ) to be copied from.

iq

(global)

INTEGER.

The row index in the global array A indicating the first row of sub( Q ).

jq

(global)

INTEGER.

The column index in the global array A indicating the first column of sub( Q ).

descq

(global and local)

INTEGER.

Array of size dlen_.

The array descriptor for the distributed matrix A.

work

(local)

REAL for pslasrt

DOUBLE PRECISION for pdlasrt

Array, size (lwork)

lwork

(local)

INTEGER.

The size of the array work.

lwork = MAX( n, NP * ( NB + NQ )), where NP = numroc( n, NB, MYROW, IAROW, NPROW ), NQ = numroc( n, NB, MYCOL, DESCQ( csrc_ ), NPCOL ).

numroc is a ScaLAPACK tool function.

iwork

(local)

INTEGER.

Array, size (liwork)

liwork

(local)

INTEGER.

The size of the array iwork.

liwork = n + 2*NB + 2*NPCOL

Output Parameters

d

On exit, the numbers in d are sorted in increasing order.

info

(global)

INTEGER.

= 0: successful exit

< 0: If the i-th argument is an array and the j-th entry had an illegal value, then info = -(i*100+j), if the i-th argument is a scalar and had an illegal value, then info = -i.