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cungr2.f(3)                         LAPACK                         cungr2.f(3)

NAME
       cungr2.f -

SYNOPSIS
   Functions/Subroutines
       subroutine cungr2 (M, N, K, A, LDA, TAU, WORK, INFO)
           CUNGR2 generates all or part of the unitary matrix Q from an RQ
           factorization determined by cgerqf (unblocked algorithm).

Function/Subroutine Documentation
   subroutine cungr2 (integerM, integerN, integerK, complex, dimension( lda, *
       )A, integerLDA, complex, dimension( * )TAU, complex, dimension( *
       )WORK, integerINFO)
       CUNGR2 generates all or part of the unitary matrix Q from an RQ
       factorization determined by cgerqf (unblocked algorithm).

       Purpose:

            CUNGR2 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 CGERQF.

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

           WORK

                     WORK is COMPLEX 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 cungr2.f.

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

Version 3.4.2                   Sat Nov 16 2013                    cungr2.f(3)