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 (characterJOB, characterSIDE, integerN, integerILO, integerIHI, real, dimension( * )SCALE, integerM, complex, dimension( ldv, * )V, integerLDV, integerINFO)

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:

November 2011

Definition at line 131 of file cgebak.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

cgebak(3) is an alias of cgebak.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK