dlctes()

logical function dlctes	(	double precision	ZR,
		double precision	ZI,
		double precision	D
	)

DLCTES

Purpose:

 DLCTES returns .TRUE. if the eigenvalue (ZR/D) + sqrt(-1)*(ZI/D)
 is to be selected (specifically, in this subroutine, if the real
 part of the eigenvalue is negative), and otherwise it returns
 .FALSE..

 It is used by the test routine DDRGES to test whether the driver
 routine DGGES successfully sorts eigenvalues.

Parameters

[in]	ZR	ZR is DOUBLE PRECISION The numerator of the real part of a complex eigenvalue (ZR/D) + i*(ZI/D).
[in]	ZI	ZI is DOUBLE PRECISION The numerator of the imaginary part of a complex eigenvalue (ZR/D) + i*(ZI).
[in]	D	D is DOUBLE PRECISION The denominator part of a complex eigenvalue (ZR/D) + i*(ZI/D).

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date

June 2016

Definition at line 70 of file dlctes.f.

*
*  -- LAPACK test routine (version 3.7.0) --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*     June 2016
*
*     .. Scalar Arguments ..
      DOUBLE PRECISION   D, ZI, ZR
*     ..
*
*  =====================================================================
*
*     .. Parameters ..
      DOUBLE PRECISION   ZERO, ONE
      parameter( zero = 0.0d+0, one = 1.0d+0 )
*     ..
*     .. Intrinsic Functions ..
      INTRINSIC          sign
*     ..
*     .. Executable Statements ..
*
      IF( d.EQ.zero ) THEN
         dlctes = ( zr.LT.zero )
      ELSE
         dlctes = ( sign( one, zr ).NE.sign( one, d ) )
      END IF
*
      RETURN
*
*     End of DLCTES
*