clctsx.f

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*> \brief \b CLCTSX
*
*  =========== DOCUMENTATION ===========
*
* Online html documentation available at
*            http://www.netlib.org/lapack/explore-html/
*
*  Definition:
*  ===========
*
*       LOGICAL          FUNCTION CLCTSX( ALPHA, BETA )
*
*       .. Scalar Arguments ..
*       COMPLEX            ALPHA, BETA
*       ..
*
*
*> \par Purpose:
*  =============
*>
*> \verbatim
*>
*> This function is used to determine what eigenvalues will be
*> selected.  If this is part of the test driver CDRGSX, do not
*> change the code UNLESS you are testing input examples and not
*> using the built-in examples.
*> \endverbatim
*
*  Arguments:
*  ==========
*
*> \param[in] ALPHA
*> \verbatim
*>          ALPHA is COMPLEX
*> \endverbatim
*>
*> \param[in] BETA
*> \verbatim
*>          BETA is COMPLEX
*>
*>          parameters to decide whether the pair (ALPHA, BETA) is
*>          selected.
*> \endverbatim
*
*  Authors:
*  ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \ingroup complex_eig
*
*  =====================================================================
      LOGICAL          FUNCTION clctsx( ALPHA, BETA )
*
*  -- LAPACK test routine --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
*     .. Scalar Arguments ..
      COMPLEX            alpha, beta
*     ..
*
*  =====================================================================
*
*     .. Parameters ..
*     REAL               ZERO
*     PARAMETER          ( ZERO = 0.0E+0 )
*     COMPLEX            CZERO
*     PARAMETER          ( CZERO = ( 0.0E+0, 0.0E+0 ) )
*     ..
*     .. Scalars in Common ..
      LOGICAL            fs
      INTEGER            i, m, mplusn, n
*     ..
*     .. Common blocks ..
      COMMON             / mn / m, n, mplusn, i, fs
*     ..
*     .. Save statement ..
      SAVE
*     ..
*     .. Executable Statements ..
*
      IF( fs ) THEN
         i = i + 1
         IF( i.LE.m ) THEN
            clctsx = .false.
         ELSE
            clctsx = .true.
         END IF
         IF( i.EQ.mplusn ) THEN
            fs = .false.
            i = 0
         END IF
      ELSE
         i = i + 1
         IF( i.LE.n ) THEN
            clctsx = .true.
         ELSE
            clctsx = .false.
         END IF
         IF( i.EQ.mplusn ) THEN
            fs = .true.
            i = 0
         END IF
      END IF
*
*      IF( BETA.EQ.CZERO ) THEN
*         CLCTSX = ( REAL( ALPHA ).GT.ZERO )
*      ELSE
*         CLCTSX = ( REAL( ALPHA/BETA ).GT.ZERO )
*      END IF
*
      RETURN
*
*     End of CLCTSX
*
      END