zgebak (l)  Linux Man Pages
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
Command to display zgebak
manual in Linux: $ man l zgebak
NAME
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
SYNOPSIS
 SUBROUTINE ZGEBAK(

JOB, SIDE, N, ILO, IHI, SCALE, M, V, LDV,
INFO )

CHARACTER
JOB, SIDE

INTEGER
IHI, ILO, INFO, LDV, M, N

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
 JOB (input) CHARACTER*1

Specifies the type of backward transformation required:
= aqNaq, do nothing, return immediately;
= aqPaq, do backward transformation for permutation only;
= aqSaq, do backward transformation for scaling only;
= aqBaq, do backward transformations for both permutation and
scaling.
JOB must be the same as the argument JOB supplied to ZGEBAL.
 SIDE (input) CHARACTER*1

= aqRaq: V contains right eigenvectors;
= aqLaq: V contains left eigenvectors.
 N (input) INTEGER

The number of rows of the matrix V. N >= 0.
 ILO (input) INTEGER

IHI (input) 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 (input) DOUBLE PRECISION array, dimension (N)

Details of the permutation and scaling factors, as returned
by ZGEBAL.
 M (input) INTEGER

The number of columns of the matrix V. M >= 0.
 V (input/output) 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 (input) INTEGER

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

= 0: successful exit
< 0: if INFO = i, the ith argument had an illegal value.
Pages related to zgebak
 zgebak (3)
 zgebal (l)  balances a general complex matrix A
 zgebd2 (l)  reduces a complex general m by n matrix A to upper or lower real bidiagonal form B by a unitary transformation
 zgebrd (l)  reduces a general complex MbyN matrix A to upper or lower bidiagonal form B by a unitary transformation
 zgecon (l)  estimates the reciprocal of the condition number of a general complex matrix A, in either the 1norm or the infinitynorm, using the LU factorization computed by ZGETRF
 zgeequ (l)  computes row and column scalings intended to equilibrate an MbyN matrix A and reduce its condition number
 zgeequb (l)  computes row and column scalings intended to equilibrate an MbyN matrix A and reduce its condition number
 zgees (l)  computes for an NbyN complex nonsymmetric matrix A, the eigenvalues, the Schur form T, and, optionally, the matrix of Schur vectors Z