CGELQF(l)		LAPACK routine (version	1.1)		    CGELQF(l)

NAME
  CGELQF - compute an LQ factorization of a complex M-by-N matrix A

SYNOPSIS

  SUBROUTINE CGELQF( M,	N, A, LDA, TAU,	WORK, LWORK, INFO )

      INTEGER	     INFO, LDA,	LWORK, M, N

      COMPLEX	     A(	LDA, * ), TAU( * ), WORK( LWORK	)

PURPOSE
  CGELQF computes an LQ	factorization of a complex M-by-N matrix A: A =	L *
  Q.

ARGUMENTS

  M	  (input) INTEGER
	  The number of	rows of	the matrix A.  M >= 0.

  N	  (input) INTEGER
	  The number of	columns	of the matrix A.  N >= 0.

  A	  (input/output) COMPLEX array,	dimension (LDA,N)
	  On entry, the	M-by-N matrix A.  On exit, the elements	on and below
	  the diagonal of the array contain the	m-by-min(m,n) lower tra-
	  pezoidal matrix L (L is lower	triangular if m	<= n); the elements
	  above	the diagonal, with the array TAU, represent the	unitary
	  matrix Q as a	product	of elementary reflectors (see Further
	  Details).  LDA     (input) INTEGER The leading dimension of the
	  array	A.  LDA	>= max(1,M).

  TAU	  (output) COMPLEX array, dimension (min(M,N))
	  The scalar factors of	the elementary reflectors (see Further
	  Details).

  WORK	  (workspace) COMPLEX array, dimension (LWORK)
	  On exit, if INFO = 0,	WORK(1)	returns	the optimal LWORK.

  LWORK	  (input) INTEGER
	  The dimension	of the array WORK.  LWORK >= max(1,M).	For optimum
	  performance LWORK >= M*NB, where NB is the optimal blocksize.

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

FURTHER	DETAILS
  The matrix Q is represented as a product of elementary reflectors

     Q = H(k)' . . . H(2)' H(1)', where	k = min(m,n).

  Each H(i) has	the form

     H(i) = I -	tau * v	* v'

  where	tau is a complex scalar, and v is a complex vector with	v(1:i-1) = 0
  and v(i) = 1;	conjg(v(i+1:n))	is stored on exit in A(i,i+1:n), and tau in
  TAU(i).


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