SRC/dopmtr.f(3)            Library Functions Manual            SRC/dopmtr.f(3)

NAME
       SRC/dopmtr.f

SYNOPSIS
   Functions/Subroutines
       subroutine dopmtr (side, uplo, trans, m, n, ap, tau, c, ldc, work,
           info)
           DOPMTR

Function/Subroutine Documentation
   subroutine dopmtr (character side, character uplo, character trans, integer
       m, integer n, double precision, dimension( * ) ap, double precision,
       dimension( * ) tau, double precision, dimension( ldc, * ) c, integer
       ldc, double precision, dimension( * ) work, integer info)
       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.

       Definition at line 148 of file dopmtr.f.

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

LAPACK                          Version 3.12.0                 SRC/dopmtr.f(3)