cunglq(3P) Sun Performance Library cunglq(3P)NAMEcunglq - generate an M-by-N complex matrix Q with orthonormal rows,
SYNOPSIS
SUBROUTINE CUNGLQ(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)
COMPLEX A(LDA,*), TAU(*), WORK(*)
INTEGER M, N, K, LDA, LWORK, INFO
SUBROUTINE CUNGLQ_64(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)
COMPLEX A(LDA,*), TAU(*), WORK(*)
INTEGER*8 M, N, K, LDA, LWORK, INFO
F95 INTERFACE
SUBROUTINE UNGLQ(M, [N], [K], A, [LDA], TAU, [WORK], [LWORK], [INFO])
COMPLEX, DIMENSION(:) :: TAU, WORK
COMPLEX, DIMENSION(:,:) :: A
INTEGER :: M, N, K, LDA, LWORK, INFO
SUBROUTINE UNGLQ_64(M, [N], [K], A, [LDA], TAU, [WORK], [LWORK],
[INFO])
COMPLEX, DIMENSION(:) :: TAU, WORK
COMPLEX, DIMENSION(:,:) :: A
INTEGER(8) :: M, N, K, LDA, LWORK, INFO
C INTERFACE
#include <sunperf.h>
void cunglq(int m, int n, int k, complex *a, int lda, complex *tau, int
*info);
void cunglq_64(long m, long n, long k, complex *a, long lda, complex
*tau, long *info);
PURPOSEcunglq generates an M-by-N complex 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 CGELQF.
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 CGELQF 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 CGELQF.
WORK (workspace)
On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
LWORK (input)
The dimension of the array WORK. LWORK >= max(1,M). For
optimum performance LWORK >= M*NB, where NB is the optimal
blocksize.
If LWORK = -1, then a workspace query is assumed; the routine
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 LWORK is issued by XERBLA.
INFO (output)
= 0: successful exit;
< 0: if INFO = -i, the i-th argument has an illegal value
6 Mar 2009 cunglq(3P)
