NAME

cungl2 - generate an m-by-n complex matrix Q with orthonormal rows,

SYNOPSIS

SUBROUTINE CUNGL2( M, N, K, A, LDA, TAU, WORK, INFO )

INTEGER INFO, K, LDA, M, N

COMPLEX A( LDA, ∗ ), TAU( ∗ ), WORK( ∗ )

#include <sunperf.h>

void cungl2(int m, int n, int k, complex ∗ca, int lda, complex ∗tau, int ∗info) ;

PURPOSE

CUNGL2 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) INTEGER
The number of rows of the matrix Q. M >= 0.

N (input) INTEGER
The number of columns of the matrix Q. N >= M.

K (input) INTEGER
The number of elementary reflectors whose product defines the matrix Q. M >= K >= 0.

A (input/output) COMPLEX array, dimension (LDA,N)
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) INTEGER
The first dimension of the array A. LDA >= max(1,M).

TAU (input) COMPLEX array, dimension (K)
TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by CGELQF.

WORK (workspace) COMPLEX array, dimension (M)

INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument has an illegal value

SunOS 5.0  —  Last change: 10 Dec 1998