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dorm2r.f(3)                         LAPACK                         dorm2r.f(3)

NAME
       dorm2r.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dorm2r (SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK,
           INFO)
           DORM2R multiplies a general matrix by the orthogonal matrix from a
           QR factorization determined by sgeqrf (unblocked algorithm).

Function/Subroutine Documentation
   subroutine dorm2r (characterSIDE, characterTRANS, integerM, integerN,
       integerK, double precision, dimension( lda, * )A, integerLDA, double
       precision, dimension( * )TAU, double precision, dimension( ldc, * )C,
       integerLDC, double precision, dimension( * )WORK, integerINFO)
       DORM2R multiplies a general matrix by the orthogonal matrix from a QR
       factorization determined by sgeqrf (unblocked algorithm).

       Purpose:

            DORM2R overwrites the general real m by n matrix C with

                  Q * C  if SIDE = 'L' and TRANS = 'N', or

                  Q**T* C  if SIDE = 'L' and TRANS = 'T', or

                  C * Q  if SIDE = 'R' and TRANS = 'N', or

                  C * Q**T if SIDE = 'R' and TRANS = 'T',

            where Q is a real orthogonal matrix defined as the product of k
            elementary reflectors

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

            as returned by DGEQRF. Q is of order m if SIDE = 'L' and of order n
            if SIDE = 'R'.

       Parameters:
           SIDE

                     SIDE is CHARACTER*1
                     = 'L': apply Q or Q**T from the Left
                     = 'R': apply Q or Q**T from the Right

           TRANS

                     TRANS is CHARACTER*1
                     = 'N': apply Q  (No transpose)
                     = 'T': apply Q**T (Transpose)

           M

                     M is INTEGER
                     The number of rows of the matrix C. M >= 0.

           N

                     N is INTEGER
                     The number of columns of the matrix C. N >= 0.

           K

                     K is INTEGER
                     The number of elementary reflectors whose product defines
                     the matrix Q.
                     If SIDE = 'L', M >= K >= 0;
                     if SIDE = 'R', N >= K >= 0.

           A

                     A is DOUBLE PRECISION array, dimension (LDA,K)
                     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.
                     A is modified by the routine but restored on exit.

           LDA

                     LDA is INTEGER
                     The leading dimension of the array A.
                     If SIDE = 'L', LDA >= max(1,M);
                     if SIDE = 'R', LDA >= max(1,N).

           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.

           C

                     C is DOUBLE PRECISION array, dimension (LDC,N)
                     On entry, the m by n matrix C.
                     On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q.

           LDC

                     LDC is INTEGER
                     The leading dimension of the array C. LDC >= max(1,M).

           WORK

                     WORK is DOUBLE PRECISION array, dimension
                                              (N) if SIDE = 'L',
                                              (M) if SIDE = 'R'

           INFO

                     INFO is INTEGER
                     = 0: successful exit
                     < 0: if INFO = -i, the i-th argument had an illegal value

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Definition at line 159 of file dorm2r.f.

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

Version 3.4.2                   Sat Nov 16 2013                    dorm2r.f(3)