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NAME
     dorml2 - overwrite the general real m by n matrix C with   Q
     *  C if SIDE = 'L' and TRANS = 'N', or   Q'* C if SIDE = 'L'
     and TRANS = 'T', or   C * Q if SIDE = 'R' and TRANS  =  'N',
     or   C * Q' if SIDE = 'R' and TRANS = 'T',

SYNOPSIS
     SUBROUTINE DORML2( SIDE, TRANS, M, N, K,  A,  LDA,  TAU,  C,
               LDC, WORK, INFO )

     CHARACTER SIDE, TRANS

     INTEGER INFO, K, LDA, LDC, M, N

     DOUBLE PRECISION A( LDA, * ), C( LDC, * ), TAU( * ), WORK( *
               )



     #include <sunperf.h>

     void dorml2(char side, char trans, int m, int n, int k, dou-
               ble  *da,  int  lda,  double *tau, double *dc, int
               ldc, int *info) ;

PURPOSE
     DORML2 overwrites the general real m by n matrix C with

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

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

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


ARGUMENTS
     SIDE      (input) CHARACTER*1
               = 'L': apply Q or Q' from the Left
               = 'R': apply Q or Q' from the Right

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

     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.

     K         (input) 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         (input) DOUBLE PRECISION array, dimension
               (LDA,M) if SIDE = 'L', (LDA,N) if SIDE =  'R'  The
               i-th row must contain the vector which defines the
               elementary reflector H(i), for i =  1,2,...,k,  as
               returned  by  DGELQF  in  the  first k rows of its
               array argument A.  A is modified  by  the  routine
               but restored on exit.

     LDA       (input) INTEGER
               The leading dimension  of  the  array  A.  LDA  >=
               max(1,K).

     TAU       (input) DOUBLE PRECISION array, dimension (K)
               TAU(i) must contain the scalar factor of the  ele-
               mentary reflector H(i), as returned by DGELQF.

     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'*C or C*Q' 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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