cgebak.f man page

cgebak.f

Synopsis

Functions/Subroutines

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

Function/Subroutine Documentation

subroutine cgebak (character JOB, character SIDE, integer N, integer ILO, integer IHI, real, dimension( * ) SCALE, integer M, complex, dimension( ldv, * ) V, integer LDV, integer INFO)

CGEBAK  

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.
Parameters:

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 CGEBAL.

SIDE

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

N

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

ILO

          ILO is INTEGER

IHI

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

SCALE

          SCALE is REAL array, dimension (N)
          Details of the permutation and scaling factors, as returned
          by CGEBAL.

M

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

V

          V is 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

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

INFO

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

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

December 2016

Definition at line 133 of file cgebak.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page cgebak(3) is an alias of cgebak.f(3).

Tue Nov 14 2017 Version 3.8.0 LAPACK