CGEBAK(l)		LAPACK routine (version	1.1)		    CGEBAK(l)

NAME
  CGEBAK - form	the right or left eigenvectors of a complex general matrix by
  backward transformation on the computed eigenvectors of the balanced matrix
  output by CGEBAL

SYNOPSIS

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

      CHARACTER	     JOB, SIDE

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

      REAL	     SCALE( * )

      COMPLEX	     V(	LDV, * )

PURPOSE
  CGEBAK forms the right or left eigenvectors of a complex general matrix by
  backward transformation on the computed eigenvectors of the balanced matrix
  output by CGEBAL.

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 CGE-
	  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 CGE-
	  BAL.

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

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

  V	  (input/output) COMPLEX array,	dimension (LDV,M)
	  On entry, the	matrix of right	or left	eigenvectors to	be
	  transformed, as returned by CHSEIN or	CTREVC.	 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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