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zungr2.f(3)                         LAPACK                         zungr2.f(3)

NAME
       zungr2.f -

SYNOPSIS
   Functions/Subroutines
       subroutine zungr2 (M, N, K, A, LDA, TAU, WORK, INFO)
           ZUNGR2 generates all or part of the unitary matrix Q from an RQ
           factorization determined by cgerqf (unblocked algorithm).

Function/Subroutine Documentation
   subroutine zungr2 (integerM, integerN, integerK, complex*16, dimension(
       lda, * )A, integerLDA, complex*16, dimension( * )TAU, complex*16,
       dimension( * )WORK, integerINFO)
       ZUNGR2 generates all or part of the unitary matrix Q from an RQ
       factorization determined by cgerqf (unblocked algorithm).

       Purpose:

            ZUNGR2 generates an m by n complex 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 H(2)**H . . . H(k)**H

            as returned by ZGERQF.

       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 COMPLEX*16 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 ZGERQF 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 COMPLEX*16 array, dimension (K)
                     TAU(i) must contain the scalar factor of the elementary
                     reflector H(i), as returned by ZGERQF.

           WORK

                     WORK is COMPLEX*16 array, dimension (M)

           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.

       Date:
           September 2012

       Definition at line 115 of file zungr2.f.

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

Version 3.4.2                   Sat Nov 16 2013                    zungr2.f(3)