zunmhr()

subroutine zunmhr	(	character	side,
		character	trans,
		integer	m,
		integer	n,
		integer	ilo,
		integer	ihi,
		complex*16, dimension( lda, * )	a,
		integer	lda,
		complex*16, dimension( * )	tau,
		complex*16, dimension( ldc, * )	c,
		integer	ldc,
		complex*16, dimension( * )	work,
		integer	lwork,
		integer	info )

ZUNMHR

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Purpose:

!>
!> ZUNMHR overwrites the general complex M-by-N matrix C with
!>
!>                 SIDE = 'L'     SIDE = 'R'
!> TRANS = 'N':      Q * C          C * Q
!> TRANS = 'C':      Q**H * C       C * Q**H
!>
!> where Q is a complex unitary matrix of order nq, with nq = m if
!> SIDE = 'L' and nq = n if SIDE = 'R'. Q is defined as the product of
!> IHI-ILO elementary reflectors, as returned by ZGEHRD:
!>
!> Q = H(ilo) H(ilo+1) . . . H(ihi-1).
!> 

Parameters

[in]	SIDE	!> SIDE is CHARACTER*1 !> = 'L': apply Q or Q**H from the Left; !> = 'R': apply Q or Q**H from the Right. !>
[in]	TRANS	!> TRANS is CHARACTER*1 !> = 'N': apply Q (No transpose) !> = 'C': apply Q**H (Conjugate transpose) !>
[in]	M	!> M is INTEGER !> The number of rows of the matrix C. M >= 0. !>
[in]	N	!> N is INTEGER !> The number of columns of the matrix C. N >= 0. !>
[in]	ILO	!> ILO is INTEGER !>
[in]	IHI	!> IHI is 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 SIDE = 'L', then 1 <= ILO <= IHI <= M, if M > 0, and !> ILO = 1 and IHI = 0, if M = 0; !> if SIDE = 'R', then 1 <= ILO <= IHI <= N, if N > 0, and !> ILO = 1 and IHI = 0, if N = 0. !>
[in]	A	!> A is COMPLEX*16 array, dimension !> (LDA,M) if SIDE = 'L' !> (LDA,N) if SIDE = 'R' !> The vectors which define the elementary reflectors, as !> returned by ZGEHRD. !>
[in]	LDA	!> LDA is INTEGER !> The leading dimension of the array A. !> LDA >= max(1,M) if SIDE = 'L'; LDA >= max(1,N) if SIDE = 'R'. !>
[in]	TAU	!> TAU is COMPLEX*16 array, dimension !> (M-1) if SIDE = 'L' !> (N-1) if SIDE = 'R' !> TAU(i) must contain the scalar factor of the elementary !> reflector H(i), as returned by ZGEHRD. !>
[in,out]	C	!> C is COMPLEX*16 array, dimension (LDC,N) !> On entry, the M-by-N matrix C. !> On exit, C is overwritten by Q*C or Q**H*C or C*Q**H or C*Q. !>
[in]	LDC	!> LDC is INTEGER !> The leading dimension of the array C. LDC >= max(1,M). !>
[out]	WORK	!> WORK is COMPLEX*16 array, dimension (MAX(1,LWORK)) !> On exit, if INFO = 0, WORK(1) returns the optimal LWORK. !>
[in]	LWORK	!> LWORK is INTEGER !> The dimension of the array WORK. !> If SIDE = 'L', LWORK >= max(1,N); !> if SIDE = 'R', LWORK >= max(1,M). !> For optimum performance LWORK >= N*NB if SIDE = 'L', and !> LWORK >= M*NB if SIDE = 'R', 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. !>
[out]	INFO	!> INFO is INTEGER !> = 0: successful exit !> < 0: if INFO = -i, the i-th argument had an illegal value !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.