CXML
        	    
LAPACK version 3.0
cunmbr(3)

PURPOSE
  CUNMBR - VECT = 'Q', CUNMBR overwrites the general complex M-by-N matrix C
  with SIDE = 'L' SIDE = 'R' TRANS = 'N'

SYNTAX
  SUBROUTINE CUNMBR( VECT, SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK,
		     LWORK, INFO )

      CHARACTER	     SIDE, TRANS, VECT

      INTEGER	     INFO, K, LDA, LDC, LWORK, M, N

      COMPLEX	     A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * )

DESCRIPTION
  If VECT = 'Q', CUNMBR 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

  If VECT = 'P', CUNMBR overwrites the general complex M-by-N matrix C with
		  SIDE = 'L'	 SIDE = 'R'
  TRANS = 'N':	    P * C	   C * P
  TRANS = 'C':	    P**H * C	   C * P**H

  Here Q and P**H are the unitary matrices determined by CGEBRD when reducing
  a complex matrix A to bidiagonal form: A = Q * B * P**H. Q and P**H are
  defined as products of elementary reflectors H(i) and G(i) respectively.

  Let nq = m if SIDE = 'L' and nq = n if SIDE = 'R'. Thus nq is the order of
  the unitary matrix Q or P**H that is applied.

  If VECT = 'Q', A is assumed to have been an NQ-by-K matrix: if nq >= k, Q =
  H(1) H(2) . . . H(k);
  if nq < k, Q = H(1) H(2) . . . H(nq-1).

  If VECT = 'P', A is assumed to have been a K-by-NQ matrix: if k < nq, P =
  G(1) G(2) . . . G(k);
  if k >= nq, P = G(1) G(2) . . . G(nq-1).

ARGUMENTS
  VECT	  (input) CHARACTER*1
	  = 'Q': apply Q or Q**H;
	  = 'P': apply P or P**H.

  SIDE	  (input) CHARACTER*1
	  = 'L': apply Q, Q**H, P or P**H from the Left;
	  = 'R': apply Q, Q**H, P or P**H from the Right.

  TRANS	  (input) CHARACTER*1
	  = 'N':  No transpose, apply Q or P;
	  = 'C':  Conjugate transpose, apply Q**H or P**H.

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

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

  K	  (input) INTEGER
	  If VECT = 'Q', the number of columns in the original matrix reduced
	  by CGEBRD.  If VECT = 'P', the number of rows in the original
	  matrix reduced by CGEBRD.  K >= 0.

  A	  (input) COMPLEX array, dimension
	  (LDA,min(nq,K)) if VECT = 'Q' (LDA,nq)	if VECT = 'P' The
	  vectors which define the elementary reflectors H(i) and G(i), whose
	  products determine the matrices Q and P, as returned by CGEBRD.

  LDA	  (input) INTEGER
	  The leading dimension of the array A.	 If VECT = 'Q', LDA >=
	  max(1,nq); if VECT = 'P', LDA >= max(1,min(nq,K)).

  TAU	  (input) COMPLEX array, dimension (min(nq,K))
	  TAU(i) must contain the scalar factor of the elementary reflector
	  H(i) or G(i) which determines Q or P, as returned by CGEBRD in the
	  array argument TAUQ or TAUP.

  C	  (input/output) COMPLEX 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 or P*C or P**H*C or C*P or C*P**H.

  LDC	  (input) INTEGER
	  The leading dimension of the array C. LDC >= max(1,M).

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

  LWORK	  (input) 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.

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