cgemqrt.f(3)

NAME
cgemqrt.f -

SYNOPSIS

  Functions/Subroutines
subroutine CGEMQRT (SIDE, TRANS, M, N, K, NB, V, LDV, T, LDT, C, LDC, WORK, INFO)
CGEMQRT

Function/Subroutine Documentation

  subroutine CGEMQRT (CHARACTERSIDE, CHARACTERTRANS, INTEGERM, INTEGERN, INTEGERK, INTEGERNB, COMPLEX, dimension( ldv, * )V, INTEGERLDV, COMPLEX, dimension( ldt, * )T, INTEGERLDT, COMPLEX, dimension( ldc, * )C, INTEGERLDC, COMPLEX, dimension( * )WORK, INTEGERINFO)

CGEMQRT

Purpose:

     CGEMQRT 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 orthogonal 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 CGEQRT.
     Q is of order M if SIDE = 'L' and of order N  if SIDE = 'R'.

Parameters:
    SIDE

              SIDE is CHARACTER*1
              = 'L': apply Q or Q**H from the Left;
              = 'R': apply Q or Q**H from the Right.

    TRANS

              TRANS is CHARACTER*1
              = 'N':  No transpose, apply Q;
              = 'C':  Transpose, apply Q**H.

    M

              M is INTEGER
              The number of rows of the matrix C. M >= 0.

    N

              N is INTEGER
              The number of columns of the matrix C. N >= 0.

    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.

    NB

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

    V

              V is COMPLEX array, dimension (LDV,K)
              The i-th column must contain the vector which defines the
              elementary reflector H(i), for i = 1,2,...,k, as returned by
              CGEQRT in the first K columns of its array argument A.

    LDV

              LDV is INTEGER
              The leading dimension of the array V.
              If SIDE = 'L', LDA >= max(1,M);
              if SIDE = 'R', LDA >= max(1,N).

    T

              T is COMPLEX array, dimension (LDT,K)
              The upper triangular factors of the block reflectors
              as returned by CGEQRT, stored as a NB-by-N matrix.

    LDT

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

    C

              C is COMPLEX 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.

    LDC

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

    WORK

              WORK is COMPLEX array. The dimension of WORK is
               N*NB if SIDE = 'L', or  M*NB if SIDE = 'R'.

    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'.

Date:
    November 2011

Definition at line 168 of file cgemqrt.f'.

Author

Generated automatically by Doxygen for LAPACK from the source code'.