DOPMTR(l)		LAPACK routine (version	1.1)		    DOPMTR(l)

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( * )

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
	  Specifies whether the	matrix Q or Q**T is applied to C:
	  = '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 illegal value


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