dorglq(3P) Sun Performance Library dorglq(3P)NAMEdorglq - generate an M-by-N real matrix Q with orthonormal rows,
SYNOPSIS
SUBROUTINE DORGLQ(M, N, K, A, LDA, TAU, WORK, LDWORK, INFO)
INTEGER M, N, K, LDA, LDWORK, INFO
DOUBLE PRECISION A(LDA,*), TAU(*), WORK(*)
SUBROUTINE DORGLQ_64(M, N, K, A, LDA, TAU, WORK, LDWORK, INFO)
INTEGER*8 M, N, K, LDA, LDWORK, INFO
DOUBLE PRECISION A(LDA,*), TAU(*), WORK(*)
F95 INTERFACE
SUBROUTINE ORGLQ(M, [N], [K], A, [LDA], TAU, [WORK], [LDWORK], [INFO])
INTEGER :: M, N, K, LDA, LDWORK, INFO
REAL(8), DIMENSION(:) :: TAU, WORK
REAL(8), DIMENSION(:,:) :: A
SUBROUTINE ORGLQ_64(M, [N], [K], A, [LDA], TAU, [WORK], [LDWORK],
[INFO])
INTEGER(8) :: M, N, K, LDA, LDWORK, INFO
REAL(8), DIMENSION(:) :: TAU, WORK
REAL(8), DIMENSION(:,:) :: A
C INTERFACE
#include <sunperf.h>
void dorglq(int m, int n, int k, double *a, int lda, double *tau, int
*info);
void dorglq_64(long m, long n, long k, double *a, long lda, double
*tau, long *info);
PURPOSEdorglq generates an M-by-N real matrix Q with orthonormal rows, which
is defined as the first M rows of a product of K elementary reflectors
of order N
Q = H(k) . . . H(2)H(1)
as returned by DGELQF.
ARGUMENTS
M (input) The number of rows of the matrix Q. M >= 0.
N (input) The number of columns of the matrix Q. N >= M.
K (input) The number of elementary reflectors whose product defines the
matrix Q. M >= K >= 0.
A (input/output)
On entry, the i-th row must contain the vector which defines
the elementary reflector H(i), for i = 1,2,...,k, as returned
by DGELQF in the first k rows of its array argument A. On
exit, the M-by-N matrix Q.
LDA (input)
The first dimension of the array A. LDA >= max(1,M).
TAU (input)
TAU(i) must contain the scalar factor of the elementary
reflector H(i), as returned by DGELQF.
WORK (workspace)
On exit, if INFO = 0, WORK(1) returns the optimal LDWORK.
LDWORK (input)
The dimension of the array WORK. LDWORK >= max(1,M). For
optimum performance LDWORK >= M*NB, where NB is the optimal
blocksize.
If LDWORK = -1, then a workspace query is assumed; the rou‐
tine only calculates the optimal size of the WORK array,
returns this value as the first entry of the WORK array, and
no error message related to LDWORK is issued by XERBLA.
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument has an illegal value
6 Mar 2009 dorglq(3P)