ADAS Subroutine cxfrac

       SUBROUTINE CXFRAC( MXNENG , MXNSHL ,
     &                    NENRGY , NMIN   , NMAX   ,
     &                    LSETL  ,
     &                    SIGNA  , FRACLA
     &                  )
C-----------------------------------------------------------------------
C
C  ****************** FORTRAN77 SUBROUTINE: CXFRAC *********************
C
C  PURPOSE:  TO CONVERT L RESOLVED PARTIAL CROSS-SECTIONS FROM
C            ABSOLUTE VALUES TO FRACTIONS OF THE N AND L RESOLVED DATA,
C            RESPECTIVELY.
C
C  CALLING PROGRAM: ADAS301/ADAS306/ADAS307/ADAS308/ADAS309
C
C  SUBROUTINE:
C
C  INPUT : (I*4)  MXNENG    = MAXIMUM NO. OF ENERGIES.
C  INPUT : (I*4)  MXNSHL    = MAXIMUM NO. OF N SHELLS.
C  INPUT : (I*4)  NENRGY    = NUMBER OF ENERGIES READ.
C  INPUT : (I*4)  NMIN      = LOWEST N-SHELL FOR WHICH DATA READ.
C  INPUT : (I*4)  NMAX      = HIGHEST N-SHELL FOR WHICH DATA READ.
C  INPUT : (L*4)  LSETL     = FLAGS IF L-RESOLVED DATA PRESENT.
C                             .TRUE.  => L-RESOLVED DATA PRESENT.
C                             .FALSE  => L-RESOLVED DATA ABSENT.
C  INPUT : (R*8)  SIGNA(,)  = N-RESOLVED CHARGE EXCHANGE CROSS-SECTIONS.
C                             UNITS: CM2
C                             1ST DIMENSION: ENERGY INDEX
C                             2ND DIMENSION: N-SHELL
C
C  I/O   : (R*8)  FRACLA(,) = L-RESOLVED CHARGE EXCHANGE CROSS-SECTIONS.
C                             INPUT : ABSOLUTE VALUES (CM2)
C                             OUTPUT: FRACTION OF N-RESOLVED DATA.
C                             1ST DIMENSION: ENERGY INDEX
C                             2ND DIMENSION: INDEXED BY I4IDFL(N,L)
C
C          (I*4)  IE        = ENERGY INDEX.
C          (I*4)  N         = N QUANTUM NUMBER.
C          (I*4)  L         = L QUANTUM NUMBER.
C          (I*4)  IDL       = L-RESOLVED DATA INDEX.
C          (I*4)  IDM       = M-RESOLVED DATA INDEX.
C
C ROUTINES:
C          ROUTINE    SOURCE    BRIEF DESCRIPTION
C          -------------------------------------------------------------
C          I4IDFL     ADAS      RETURNS UNIQUE INDEX FROM QUANTUM
C                               NUMBERS N AND L.
C          I4IDFM     ADAS      RETURNS UNIQUE INDEX FROM QUANTUM
C                               NUMBERS N, L AND M.
C
C AUTHOR:  JONATHAN NASH (TESSELLA SUPPORT SERVICES PLC)
C          K1/0/81
C          JET EXT. 5183
C
C DATE:    15/09/93
C
C VERSION  : 1.2
C DATE     : 22-05-2007
C MODIFIED : Martin O'Mullane
C              - Remove unused m-subshell data possibility.
C
C-----------------------------------------------------------------------
C-----------------------------------------------------------------------
      INTEGER             MXNENG,      MXNSHL,      NENRGY,      NMAX
      INTEGER             NMIN
      LOGICAL             LSETL
      REAL*8              FRACLA(MXNENG,(MXNSHL*(MXNSHL+1))/2)
      REAL*8              SIGNA(MXNENG,MXNSHL)