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cung2l.f(3)                         LAPACK                         cung2l.f(3)

NAME
       cung2l.f -

SYNOPSIS
   Functions/Subroutines
       subroutine cung2l (M, N, K, A, LDA, TAU, WORK, INFO)
           CUNG2L generates all or part of the unitary matrix Q from a QL
           factorization determined by cgeqlf (unblocked algorithm).

Function/Subroutine Documentation
   subroutine cung2l (integerM, integerN, integerK, complex, dimension( lda, *
       )A, integerLDA, complex, dimension( * )TAU, complex, dimension( *
       )WORK, integerINFO)
       CUNG2L generates all or part of the unitary matrix Q from a QL
       factorization determined by cgeqlf (unblocked algorithm).

       Purpose:

            CUNG2L generates an m by n complex matrix Q with orthonormal columns,
            which is defined as the last n columns of a product of k elementary
            reflectors of order m

                  Q  =  H(k) . . . H(2) H(1)

            as returned by CGEQLF.

       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. M >= N >= 0.

           K

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

           A

                     A is COMPLEX array, dimension (LDA,N)
                     On entry, the (n-k+i)-th column must contain the vector which
                     defines the elementary reflector H(i), for i = 1,2,...,k, as
                     returned by CGEQLF in the last k columns 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 CGEQLF.

           WORK

                     WORK is COMPLEX array, dimension (N)

           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 cung2l.f.

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

Version 3.4.2                   Sat Nov 16 2013                    cung2l.f(3)