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## zgemlqt()

subroutine zgemlqt | ( | character | side,
|  | character | trans,
|  | integer | m,
|  | integer | n,
|  | integer | k,
|  | integer | mb,
|  | complex*16, dimension( ldv, * ) | v,
|  | integer | ldv,
|  | complex*16, dimension( ldt, * ) | t,
|  | integer | ldt,
|  | complex*16, dimension( ldc, * ) | c,
|  | integer | ldc,
|  | complex*16, dimension( * ) | work,
|  | integer | info )

ZGEMLQT

Download ZGEMLQT + dependencies [TGZ] [ZIP] [TXT]

Purpose:

      !>
      !> ZGEMLQT 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 defined as the product of K
      !> elementary reflectors:
      !>
      !>       Q = H(1) H(2) . . . H(K) = I - V T V**H
      !>
      !> generated using the compact WY representation as returned by ZGELQT.
      !>
      !> Q is of order M if SIDE = 'L' and of order N  if SIDE = 'R'.
      !>

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':  No transpose, apply Q;
      !>          = 'C':  Conjugate transpose, apply Q**H.
      !>

  [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]

  K

      !>          K is INTEGER
      !>          The number of elementary reflectors whose product defines
      !>          the matrix Q.
      !>          If SIDE = 'L', M >= K >= 0;
      !>          if SIDE = 'R', N >= K >= 0.
      !>

  [in]

  MB

      !>          MB is INTEGER
      !>          The block size used for the storage of T.  K >= MB >= 1.
      !>          This must be the same value of MB used to generate T
      !>          in ZGELQT.
      !>

  [in]

  V

      !>          V is COMPLEX*16 array, dimension
      !>                               (LDV,M) if SIDE = 'L',
      !>                               (LDV,N) if SIDE = 'R'
      !>          The i-th row must contain the vector which defines the
      !>          elementary reflector H(i), for i = 1,2,...,k, as returned by
      !>          ZGELQT in the first K rows of its array argument A.
      !>

  [in]

  LDV

      !>          LDV is INTEGER
      !>          The leading dimension of the array V. LDV >= max(1,K).
      !>

  [in]

  T

      !>          T is COMPLEX*16 array, dimension (LDT,K)
      !>          The upper triangular factors of the block reflectors
      !>          as returned by ZGELQT, stored as a MB-by-K matrix.
      !>

  [in]

  LDT

      !>          LDT is INTEGER
      !>          The leading dimension of the array T.  LDT >= MB.
      !>

  [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, Q**H C, 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. The dimension of
      !>          WORK is N*MB if SIDE = 'L', or  M*MB if SIDE = 'R'.
      !>

  [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.