SRC/cgelqt.f(3)            Library Functions Manual            SRC/cgelqt.f(3)

NAME
       SRC/cgelqt.f

SYNOPSIS
   Functions/Subroutines
       subroutine cgelqt (m, n, mb, a, lda, t, ldt, work, info)
           CGELQT

Function/Subroutine Documentation
   subroutine cgelqt (integer m, integer n, integer mb, complex, dimension(
       lda, * ) a, integer lda, complex, dimension( ldt, * ) t, integer ldt,
       complex, dimension( * ) work, integer info)
       CGELQT

       Purpose:


           !>
           !> CGELQT computes a blocked LQ factorization of a complex M-by-N matrix A
           !> using the compact WY representation of Q.
           !>

       Parameters
           M

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

           N

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

           MB

           !>          MB is INTEGER
           !>          The block size to be used in the blocked QR.  MIN(M,N) >= MB >= 1.
           !>

           A

           !>          A is COMPLEX array, dimension (LDA,N)
           !>          On entry, the M-by-N matrix A.
           !>          On exit, the elements on and below the diagonal of the array
           !>          contain the M-by-MIN(M,N) lower trapezoidal matrix L (L is
           !>          lower triangular if M <= N); the elements above the diagonal
           !>          are the rows of V.
           !>

           LDA

           !>          LDA is INTEGER
           !>          The leading dimension of the array A.  LDA >= max(1,M).
           !>

           T

           !>          T is COMPLEX array, dimension (LDT,MIN(M,N))
           !>          The upper triangular block reflectors stored in compact form
           !>          as a sequence of upper triangular blocks.  See below
           !>          for further details.
           !>

           LDT

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

           WORK

           !>          WORK is COMPLEX array, dimension (MB*N)
           !>

           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.

       Further Details:


           !>
           !>  The matrix V stores the elementary reflectors H(i) in the i-th row
           !>  above the diagonal. For example, if M=5 and N=3, the matrix V is
           !>
           !>               V = (  1  v1 v1 v1 v1 )
           !>                   (     1  v2 v2 v2 )
           !>                   (         1 v3 v3 )
           !>
           !>
           !>  where the vi's represent the vectors which define H(i), which are returned
           !>  in the matrix A.  The 1's along the diagonal of V are not stored in A.
           !>  Let K=MIN(M,N).  The number of blocks is B = ceiling(K/MB), where each
           !>  block is of order MB except for the last block, which is of order
           !>  IB = K - (B-1)*MB.  For each of the B blocks, a upper triangular block
           !>  reflector factor is computed: T1, T2, ..., TB.  The MB-by-MB (and IB-by-IB
           !>  for the last block) T's are stored in the MB-by-K matrix T as
           !>
           !>               T = (T1 T2 ... TB).
           !>

       Definition at line 123 of file cgelqt.f.

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

LAPACK                          Version 3.12.0                 SRC/cgelqt.f(3)