gebak - Man Page

subroutine cgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info)
CGEBAK
subroutine dgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info)
DGEBAK
subroutine sgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info)
SGEBAK
subroutine zgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info)
ZGEBAK

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.

Definition at line 129 of file cgebak.f.

DGEBAK  

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.

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 DGEBAL.

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 DGEBAL.
          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 DGEBAL.

M

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

V

          V is 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

          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 128 of file dgebak.f.

SGEBAK  

Purpose:

 SGEBAK forms the right or left eigenvectors of a real general matrix
 by backward transformation on the computed eigenvectors of the
 balanced matrix output by SGEBAL.

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 SGEBAL.

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 SGEBAL.
          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 SGEBAL.

M

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

V

          V is REAL array, dimension (LDV,M)
          On entry, the matrix of right or left eigenvectors to be
          transformed, as returned by SHSEIN or STREVC.
          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 128 of file sgebak.f.

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.