ZSLECT
Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
February 2007
February 2007
Purpose
ZSLECT returns .TRUE. if the eigenvalue Z is to be selected,
otherwise it returns .FALSE.
It is used by ZCHK41 to test if ZGEES succesfully sorts eigenvalues,
and by ZCHK43 to test if ZGEESX succesfully sorts eigenvalues.
The common block /SSLCT/ controls how eigenvalues are selected.
If SELOPT = 0, then ZSLECT return .TRUE. when real(Z) is less than
zero, and .FALSE. otherwise.
If SELOPT is at least 1, ZSLECT returns SELVAL(SELOPT) and adds 1
to SELOPT, cycling back to 1 at SELMAX.
otherwise it returns .FALSE.
It is used by ZCHK41 to test if ZGEES succesfully sorts eigenvalues,
and by ZCHK43 to test if ZGEESX succesfully sorts eigenvalues.
The common block /SSLCT/ controls how eigenvalues are selected.
If SELOPT = 0, then ZSLECT return .TRUE. when real(Z) is less than
zero, and .FALSE. otherwise.
If SELOPT is at least 1, ZSLECT returns SELVAL(SELOPT) and adds 1
to SELOPT, cycling back to 1 at SELMAX.
Arguments
| Z |
(input) COMPLEX*16
The eigenvalue Z.
|