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zgebak examples
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Man Page Details
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 Online html documentation available at 
            http://www.netlib.org/lapack/explore-html/ 

  Definition:
  ===========

       SUBROUTINE ZGEBAK( JOB, SIDE, N, ILO, IHI, SCALE, M, V, LDV,
                          INFO )
 
       .. Scalar Arguments ..
       CHARACTER          JOB, SIDE
       INTEGER            IHI, ILO, INFO, LDV, M, N
       ..
       .. Array Arguments ..
       DOUBLE PRECISION   SCALE( * )
       COMPLEX*16         V( LDV, * )
       ..
  

  Purpose:
  =============

   ZGEBAK forms the right or left eigenvectors of a complex general
   matrix by backward transformation on the computed eigenvectors of the
   balanced matrix output by ZGEBAL.

  Arguments:
  ==========

  [in] JOB

          JOB is 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 ZGEBAL.

  [in] SIDE

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

  [in] N

          N is INTEGER
          The number of rows of the matrix V.  N >= 0.

  [in] ILO

          ILO is INTEGER

  [in] IHI

          IHI is INTEGER
          The integers ILO and IHI determined by ZGEBAL.
          1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0.


  [in] SCALE

          SCALE is DOUBLE PRECISION array, dimension (N)
          Details of the permutation and scaling factors, as returned
          by ZGEBAL.


  [in] M

          M is INTEGER
          The number of columns of the matrix V.  M >= 0.

  [in,out] V

          V is COMPLEX*16 array, dimension (LDV,M)
          On entry, the matrix of right or left eigenvectors to be
          transformed, as returned by ZHSEIN or ZTREVC.
          On exit, V is overwritten by the transformed eigenvectors.

  [in] LDV

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

  [out] INFO

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

  Authors:
  ========

   Univ. of Tennessee 
   Univ. of California Berkeley 
   Univ. of Colorado Denver 
   NAG Ltd. 

 November 2011

