ZUPGTR(l)		LAPACK routine (version	1.1)		    ZUPGTR(l)

NAME
  ZUPGTR - generate a complex unitary matrix Q which is	defined	as the pro-
  duct of n-1 elementary reflectors of order n,	as returned by ZHPTRD using
  packed storage

SYNOPSIS

  SUBROUTINE ZUPGTR( UPLO, N, AP, TAU, Q, LDQ, WORK, INFO )

      CHARACTER	     UPLO

      INTEGER	     INFO, LDQ,	N

      COMPLEX*16     AP( * ), Q( LDQ, *	), TAU(	* ), WORK( * )

PURPOSE
  ZUPGTR generates a complex unitary matrix Q which is defined as the product
  of n-1 elementary reflectors of order	n, as returned by ZHPTRD using packed
  storage:

  if UPLO = 'U', Q = H(n-1) . .	. H(2) H(1),

  if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).

ARGUMENTS

  UPLO	  (input) CHARACTER*1
	  = 'U': Upper triangular packed storage used in previous call to
	  ZHPTRD; = 'L': Lower triangular packed storage used in previous
	  call to ZHPTRD.

  N	  (input) INTEGER
	  The order of the matrix Q. N >= 0.

  AP	  (input) COMPLEX*16 array, dimension (N*(N+1)/2)
	  The vectors which define the elementary reflectors, as returned by
	  ZHPTRD.

  TAU	  (input) COMPLEX*16 array, dimension (N-1)
	  TAU(i) must contain the scalar factor	of the elementary reflector
	  H(i),	as returned by ZHPTRD.

  Q	  (output) COMPLEX*16 array, dimension (LDQ,N)
	  The N-by-N unitary matrix Q.

  LDQ	  (input) INTEGER
	  The leading dimension	of the array Q.	LDQ >= max(1,N).

  WORK	  (workspace) COMPLEX*16 array,	dimension (N-1)

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


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