ADAS Subroutine etred

       FUNCTION ETRED( KTYPE , E , T ,  C)
C-----------------------------------------------------------------------
C
C  ******************** FORTRAN 77 FUNCTION: ETRED *********************
C
C  PURPOSE:  TO CALCULATE THE REDUCED ENERGY FOR FOUR TYPES OF 
C            TRANSITION
C
C  CALLING PROGRAM: VARIOUS ADAS101 CODES
C
C  FUNCTION:
C
C  INPUT:    (R*8)    E      =   TRANSITION ENERGY (Eij)
C            (R*8)    T      =   COLLIDING ELECTRON ENERGY AFTER 
C                                EXCITATION (Ej)
C            (R*8)    C      =   ADJUSTABLE SCALING PARAMETER
C            (R*8)    TL     =   Ej/Eij
C            (I)      KTYPE  =   TRANSITION TYPE
C                                1 ELECTRIC DIPOLE
C                                2 NON ELECTRIC DIPOLE
C                                3 SPIN CHANGE
C                                4 OTHER
C
C  OUTPUT:   (R*8)    ETRED  =   REDUCED ENERGY
C
C 
C  ROUTINES: NONE
C
C  DATE:     21/06/95				VERSION 1.1
C  AUTHOR:   A.LANZAFAME (UNIV. OF STRATHCLYDE) & D.H.BROOKS
C
C-----------------------------------------------------------------------
      INTEGER             KTYPE
      REAL*8              C,           E,           T