sslect.f3
Usage
Functions/Subroutines
logical function sslect (zr, zi)
SSLECT
Function/Subroutine Documentation
logical function sslect (real zr, real zi)
SSLECT
Purpose:
!> !> SSLECT returns .TRUE. if the eigenvalue ZR+sqrt(-1)*ZI is to be !> selected, and otherwise it returns .FALSE. !> It is used by SCHK41 to test if SGEES successfully sorts eigenvalues, !> and by SCHK43 to test if SGEESX successfully sorts eigenvalues. !> !> The common block /SSLCT/ controls how eigenvalues are selected. !> If SELOPT = 0, then SSLECT return .TRUE. when ZR is less than zero, !> and .FALSE. otherwise. !> If SELOPT is at least 1, SSLECT returns SELVAL(SELOPT) and adds 1 !> to SELOPT, cycling back to 1 at SELMAX. !>
Parameters
ZR
!> ZR is REAL !> The real part of a complex eigenvalue ZR + i*ZI. !>
ZI
!> ZI is REAL !> The imaginary part of a complex eigenvalue ZR + i*ZI. !>
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Definition at line 61 of file sslect.f.