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NAME
     dopmtr - overwrite the general real  M-by-N  matrix  C  with
     SIDE = 'L' SIDE = 'R' TRANS = 'N'

SYNOPSIS
     SUBROUTINE DOPMTR( SIDE, UPLO, TRANS, M, N, AP, TAU, C, LDC,
               WORK, INFO )

     CHARACTER SIDE, TRANS, UPLO

     INTEGER INFO, LDC, M, N

     DOUBLE PRECISION AP( * ), C( LDC, * ), TAU( * ), WORK( * )



     #include <sunperf.h>

     void dopmtr(char side, char uplo, char trans, int m, int  n,
               double *dap, double *tau, double *dc, int ldc, int
               *info) ;

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


ARGUMENTS
     SIDE      (input) CHARACTER*1
               = 'L': apply Q or Q**T from the Left;
               = 'R': apply Q or Q**T from the Right.

     UPLO      (input) 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     (input) CHARACTER*1
               = 'N':  No transpose, apply Q;
               = 'T':  Transpose, apply Q**T.

     M         (input) INTEGER
               The number of rows of the matrix C. M >= 0.

     N         (input) INTEGER
               The number of columns of the matrix C. N >= 0.

     AP        (input) 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       (input) 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         (input/output) 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       (input) INTEGER
               The leading dimension  of  the  array  C.  LDC  >=
               max(1,M).

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

     INFO      (output) INTEGER
               = 0:  successful exit
               < 0:  if INFO = -i, the i-th argument had an ille-
               gal value

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