DGEBAK(l)		LAPACK routine (version	1.1)		    DGEBAK(l)

NAME
  DGEBAK - form	the right or left eigenvectors of a real general matrix	by
  backward transformation on the computed eigenvectors of the balanced matrix
  output by DGEBAL

SYNOPSIS

  SUBROUTINE DGEBAK( JOB, SIDE,	N, ILO,	IHI, SCALE, M, V, LDV, INFO )

      CHARACTER	     JOB, SIDE

      INTEGER	     IHI, ILO, INFO, LDV, M, N

      DOUBLE	     PRECISION SCALE( *	), V( LDV, * )

PURPOSE
  DGEBAK forms the right or left eigenvectors of a real	general	matrix by
  backward transformation on the computed eigenvectors of the balanced matrix
  output by DGEBAL.

ARGUMENTS

  JOB	  (input) CHARACTER*1
	  Specifies the	type of	backward transformation	required: = 'N', do
	  nothing, return immediately; = 'P', do backward transformation for
	  permutation only; = 'S', do backward transformation for scaling
	  only;	= 'B', do backward transformations for both permutation	and
	  scaling.  JOB	must be	the same as the	argument JOB supplied to DGE-
	  BAL.

  SIDE	  (input) CHARACTER*1
	  = 'R':  V contains right eigenvectors;
	  = 'L':  V contains left eigenvectors.

  N	  (input) INTEGER
	  The number of	rows of	the matrix V.  N >= 0.

  ILO	  (input) INTEGER
	  IHI	  (input) INTEGER The integers ILO and IHI determined by DGE-
	  BAL.

  SCALE	  (input) DOUBLE PRECISION array, dimension (N)
	  Details of the permutation and scaling factors, as returned by DGE-
	  BAL.

  M	  (input) INTEGER
	  The number of	columns	of the matrix V.

  V	  (input/output) DOUBLE	PRECISION array, dimension (LDV,M)
	  On entry, the	matrix of right	or left	eigenvectors to	be
	  transformed, as returned by DHSEIN or	DTREVC.	 On exit, V is
	  overwritten by the transformed eigenvectors.

  LDV	  (input) INTEGER
	  The leading dimension	of the array V.	LDV >= max(1,N).

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


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