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dopmtr.f(3)                         LAPACK                         dopmtr.f(3)

NAME
       dopmtr.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dopmtr (SIDE, UPLO, TRANS, M, N, AP, TAU, C, LDC, WORK,
           INFO)
           DOPMTR

Function/Subroutine Documentation
   subroutine dopmtr (characterSIDE, characterUPLO, characterTRANS, integerM,
       integerN, double precision, dimension( * )AP, double precision,
       dimension( * )TAU, double precision, dimension( ldc, * )C, integerLDC,
       double precision, dimension( * )WORK, integerINFO)
       DOPMTR

       Purpose:

            DOPMTR overwrites the general real M-by-N matrix C with

                            SIDE = 'L'     SIDE = 'R'
            TRANS = 'N':      Q * C          C * Q
            TRANS = 'T':      Q**T * C       C * Q**T

            where Q is a real orthogonal matrix of order nq, with nq = m if
            SIDE = 'L' and nq = n if SIDE = 'R'. Q is defined as the product of
            nq-1 elementary reflectors, as returned by DSPTRD using packed
            storage:

            if UPLO = 'U', Q = H(nq-1) . . . H(2) H(1);

            if UPLO = 'L', Q = H(1) H(2) . . . H(nq-1).

       Parameters:
           SIDE

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

           UPLO

                     UPLO is CHARACTER*1
                     = 'U': Upper triangular packed storage used in previous
                            call to DSPTRD;
                     = 'L': Lower triangular packed storage used in previous
                            call to DSPTRD.

           TRANS

                     TRANS is CHARACTER*1
                     = 'N':  No transpose, apply Q;
                     = 'T':  Transpose, apply Q**T.

           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.

           AP

                     AP is DOUBLE PRECISION array, dimension
                                          (M*(M+1)/2) if SIDE = 'L'
                                          (N*(N+1)/2) if SIDE = 'R'
                     The vectors which define the elementary reflectors, as
                     returned by DSPTRD.  AP is modified by the routine but
                     restored on exit.

           TAU

                     TAU is DOUBLE PRECISION array, dimension (M-1) if SIDE = 'L'
                                                or (N-1) if SIDE = 'R'
                     TAU(i) must contain the scalar factor of the elementary
                     reflector H(i), as returned by DSPTRD.

           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:
           November 2011

       Definition at line 150 of file dopmtr.f.

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

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