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

NAME
       SRC/dorgrq.f

SYNOPSIS
   Functions/Subroutines
       subroutine dorgrq (m, n, k, a, lda, tau, work, lwork, info)
           DORGRQ

Function/Subroutine Documentation
   subroutine dorgrq (integer m, integer n, integer k, double precision,
       dimension( lda, * ) a, integer lda, double precision, dimension( * )
       tau, double precision, dimension( * ) work, integer lwork, integer
       info)
       DORGRQ

       Purpose:


           !>
           !> DORGRQ generates an M-by-N real matrix Q with orthonormal rows,
           !> which is defined as the last M rows of a product of K elementary
           !> reflectors of order N
           !>
           !>       Q  =  H(1) H(2) . . . H(k)
           !>
           !> as returned by DGERQF.
           !>

       Parameters
           M

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

           N

           !>          N is INTEGER
           !>          The number of columns of the matrix Q. N >= M.
           !>

           K

           !>          K is INTEGER
           !>          The number of elementary reflectors whose product defines the
           !>          matrix Q. M >= K >= 0.
           !>

           A

           !>          A is DOUBLE PRECISION array, dimension (LDA,N)
           !>          On entry, the (m-k+i)-th row must contain the vector which
           !>          defines the elementary reflector H(i), for i = 1,2,...,k, as
           !>          returned by DGERQF in the last k rows of its array argument
           !>          A.
           !>          On exit, the M-by-N matrix Q.
           !>

           LDA

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

           TAU

           !>          TAU is DOUBLE PRECISION array, dimension (K)
           !>          TAU(i) must contain the scalar factor of the elementary
           !>          reflector H(i), as returned by DGERQF.
           !>

           WORK

           !>          WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK))
           !>          On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
           !>

           LWORK

           !>          LWORK is INTEGER
           !>          The dimension of the array WORK. LWORK >= max(1,M).
           !>          For optimum performance LWORK >= M*NB, 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

           !>          INFO is INTEGER
           !>          = 0:  successful exit
           !>          < 0:  if INFO = -i, the i-th argument has an illegal value
           !>

       Author
           Univ. of Tennessee


           Univ. of California Berkeley


           Univ. of Colorado Denver


           NAG Ltd.

       Definition at line 127 of file dorgrq.f.

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

LAPACK                          Version 3.12.0                 SRC/dorgrq.f(3)