108 lines
2.7 KiB
Fortran
108 lines
2.7 KiB
Fortran
*> \brief \b CLCTES
|
|
*
|
|
* =========== DOCUMENTATION ===========
|
|
*
|
|
* Online html documentation available at
|
|
* http://www.netlib.org/lapack/explore-html/
|
|
*
|
|
* Definition:
|
|
* ===========
|
|
*
|
|
* LOGICAL FUNCTION CLCTES( Z, D )
|
|
*
|
|
* .. Scalar Arguments ..
|
|
* COMPLEX D, Z
|
|
* ..
|
|
*
|
|
*
|
|
*> \par Purpose:
|
|
* =============
|
|
*>
|
|
*> \verbatim
|
|
*>
|
|
*> CLCTES returns .TRUE. if the eigenvalue Z/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 CDRGES to test whether the driver
|
|
*> routine CGGES succesfully sorts eigenvalues.
|
|
*> \endverbatim
|
|
*
|
|
* Arguments:
|
|
* ==========
|
|
*
|
|
*> \param[in] Z
|
|
*> \verbatim
|
|
*> Z is COMPLEX
|
|
*> The numerator part of a complex eigenvalue Z/D.
|
|
*> \endverbatim
|
|
*>
|
|
*> \param[in] D
|
|
*> \verbatim
|
|
*> D is COMPLEX
|
|
*> The denominator part of a complex eigenvalue Z/D.
|
|
*> \endverbatim
|
|
*
|
|
* Authors:
|
|
* ========
|
|
*
|
|
*> \author Univ. of Tennessee
|
|
*> \author Univ. of California Berkeley
|
|
*> \author Univ. of Colorado Denver
|
|
*> \author NAG Ltd.
|
|
*
|
|
*> \date November 2011
|
|
*
|
|
*> \ingroup complex_eig
|
|
*
|
|
* =====================================================================
|
|
LOGICAL FUNCTION CLCTES( Z, D )
|
|
*
|
|
* -- LAPACK test routine (version 3.4.0) --
|
|
* -- LAPACK is a software package provided by Univ. of Tennessee, --
|
|
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
|
|
* November 2011
|
|
*
|
|
* .. Scalar Arguments ..
|
|
COMPLEX D, Z
|
|
* ..
|
|
*
|
|
* =====================================================================
|
|
*
|
|
* .. Parameters ..
|
|
*
|
|
REAL ZERO, ONE
|
|
PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 )
|
|
COMPLEX CZERO
|
|
PARAMETER ( CZERO = ( 0.0E+0, 0.0E+0 ) )
|
|
* ..
|
|
* .. Local Scalars ..
|
|
REAL ZMAX
|
|
* ..
|
|
* .. Intrinsic Functions ..
|
|
INTRINSIC ABS, AIMAG, MAX, REAL, SIGN
|
|
* ..
|
|
* .. Executable Statements ..
|
|
*
|
|
IF( D.EQ.CZERO ) THEN
|
|
CLCTES = ( REAL( Z ).LT.ZERO )
|
|
ELSE
|
|
IF( REAL( Z ).EQ.ZERO .OR. REAL( D ).EQ.ZERO ) THEN
|
|
CLCTES = ( SIGN( ONE, AIMAG( Z ) ).NE.
|
|
$ SIGN( ONE, AIMAG( D ) ) )
|
|
ELSE IF( AIMAG( Z ).EQ.ZERO .OR. AIMAG( D ).EQ.ZERO ) THEN
|
|
CLCTES = ( SIGN( ONE, REAL( Z ) ).NE.
|
|
$ SIGN( ONE, REAL( D ) ) )
|
|
ELSE
|
|
ZMAX = MAX( ABS( REAL( Z ) ), ABS( AIMAG( Z ) ) )
|
|
CLCTES = ( ( REAL( Z ) / ZMAX )*REAL( D )+
|
|
$ ( AIMAG( Z ) / ZMAX )*AIMAG( D ).LT.ZERO )
|
|
END IF
|
|
END IF
|
|
*
|
|
RETURN
|
|
*
|
|
* End of CLCTES
|
|
*
|
|
END
|