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dorg2r.f(3)                         LAPACK                         dorg2r.f(3)

NAME
       dorg2r.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dorg2r (M, N, K, A, LDA, TAU, WORK, INFO)
           DORG2R generates all or part of the orthogonal matrix Q from a QR
           factorization determined by sgeqrf (unblocked algorithm).

Function/Subroutine Documentation
   subroutine dorg2r (integerM, integerN, integerK, double precision,
       dimension( lda, * )A, integerLDA, double precision, dimension( * )TAU,
       double precision, dimension( * )WORK, integerINFO)
       DORG2R generates all or part of the orthogonal matrix Q from a QR
       factorization determined by sgeqrf (unblocked algorithm).

       Purpose:

            DORG2R generates an m by n real matrix Q with orthonormal columns,
            which is defined as the first n columns of a product of k elementary
            reflectors of order m

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

            as returned by DGEQRF.

       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 DOUBLE PRECISION array, dimension (LDA,N)
                     On entry, the i-th column must contain the vector which
                     defines the elementary reflector H(i), for i = 1,2,...,k, as
                     returned by DGEQRF in the first 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 DOUBLE PRECISION array, dimension (K)
                     TAU(i) must contain the scalar factor of the elementary
                     reflector H(i), as returned by DGEQRF.

           WORK

                     WORK is DOUBLE PRECISION 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 dorg2r.f.

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

Version 3.4.2                   Sat Nov 16 2013                    dorg2r.f(3)