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sorgr2.f(3)                         LAPACK                         sorgr2.f(3)

NAME
       sorgr2.f -

SYNOPSIS
   Functions/Subroutines
       subroutine sorgr2 (M, N, K, A, LDA, TAU, WORK, INFO)
           SORGR2 generates all or part of the orthogonal matrix Q from an RQ
           factorization determined by sgerqf (unblocked algorithm).

Function/Subroutine Documentation
   subroutine sorgr2 (integerM, integerN, integerK, real, dimension( lda, *
       )A, integerLDA, real, dimension( * )TAU, real, dimension( * )WORK,
       integerINFO)
       SORGR2 generates all or part of the orthogonal matrix Q from an RQ
       factorization determined by sgerqf (unblocked algorithm).

       Purpose:

            SORGR2 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 SGERQF.

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

           WORK

                     WORK is REAL 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 sorgr2.f.

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

Version 3.4.2                   Sat Nov 16 2013                    sorgr2.f(3)