ZUNGHR(l)		LAPACK routine (version	1.1)		    ZUNGHR(l)

NAME
  ZUNGHR - generate a complex unitary matrix Q which is	defined	as the pro-
  duct of IHI-ILO elementary reflectors	of order N, as returned	by ZGEHRD

SYNOPSIS

  SUBROUTINE ZUNGHR( N,	ILO, IHI, A, LDA, TAU, WORK, LWORK, INFO )

      INTEGER	     IHI, ILO, INFO, LDA, LWORK, N

      COMPLEX*16     A(	LDA, * ), TAU( * ), WORK( LWORK	)

PURPOSE
  ZUNGHR generates a complex unitary matrix Q which is defined as the product
  of IHI-ILO elementary	reflectors of order N, as returned by ZGEHRD:

  Q = H(ilo) H(ilo+1) .	. . H(ihi-1).

ARGUMENTS

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

  ILO	  (input) INTEGER
	  IHI	  (input) INTEGER ILO and IHI must have	the same values	as in
	  the previous call of ZGEHRD. Q is equal to the unit matrix except
	  in the submatrix Q(ilo+1:ihi,ilo+1:ihi).  If N > 0, 1	<= ILO <= IHI
	  <= N;	otherwise ILO =	1 and IHI = N.

  A	  (input/output) COMPLEX*16 array, dimension (LDA,N)
	  On entry, the	vectors	which define the elementary reflectors,	as
	  returned by ZGEHRD.  On exit,	the N-by-N unitary matrix Q.

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

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

  WORK	  (workspace) COMPLEX*16 array,	dimension (LWORK)
	  On exit, if INFO = 0,	WORK(1)	returns	the optimal LWORK.

  LWORK	  (input) INTEGER
	  The dimension	of the array WORK. LWORK >= IHI-ILO.  For optimum
	  performance LWORK >= (IHI-ILO)*NB, where NB is the optimal block-
	  size.

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


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