zgebak.f(3)

zgebak.f3

Usage

Functions/Subroutines

subroutine zgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info)
ZGEBAK

Function/Subroutine Documentation

subroutine zgebak (character job, character side, integer n, integer ilo, integer ihi, double precision, dimension( * ) scale, integer m, complex*16, dimension( ldv, * ) v, integer ldv, integer info)

ZGEBAK

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.
!> 

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 ZGEBAL.
!> 

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 ZGEBAL.
!>          1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0.
!> 

SCALE

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

M

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

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.
!> 

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.

Definition at line 129 of file zgebak.f.

Releases

4 releases since Debian 7 (Wheezy); the text changed 3 times.

  1. 7
  2. 8
  3. 9
  4. Arch

Author

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