ADAS Subroutine xxsion

      SUBROUTINE XXSION( SYMB , IZ , SION , LEN )
C
C
C-----------------------------------------------------------------------
C
C  ****************** FORTRAN77 SUBROUTINE: XXSION *********************
C
C  PURPOSE: RETURNS ION ELEMENT SYMBOL AND ION CHARGE AS A STRING
C           CONSTRUCTED AS FOLLOWS <SYMBOL><CHARGE>. IT ALSO RETURNS
C           THE LENGTH OF THE STRING.
C
C  CALLING PROGRAM: GENERAL USE
C
C  SUBROUTINE:
C
C  INPUT : (C*2)  SYMB      = ION ELEMENT SYMBOL OF BEAM.
C  INPUT : (I*4)  IZ        = ION CHARGE
C
C  INPUT : (C*4)  SION      = ION STRING '<SYMBOL><CHARGE>'.
C  INPUT : (I*4)  LEN       = LENGTH OF ION STRING.
C
C          (I*4)  I         = LENGTH IN BYTES OF NON-BLANK 'DSNAME'.
C
C ROUTINES: NONE
C
C AUTHOR:  JONATHAN NASH  (TESSELLA SUPPORT SERVICES PLC)
C          K1/0/87
C          JET EXT. 5183
C
C DATE:    21/12/93
C
C UNIX-IDL PORT:
C
C VERSION: 1.1                          DATE: 16-11-95
C MODIFIED: TIM HAMMOND (TESSELLA SUPPORT SERVICES PLC)
C               - FIRST VERSION
C
C-----------------------------------------------------------------------
C
C-----------------------------------------------------------------------
      CHARACTER*4         SION
      CHARACTER*2         SYMB
      INTEGER             IZ,          LEN