C DATA2A              INDICES FOR DATA ARRAY
C
C NEL                    TOTAL NUMBER OF ELEMENTS IN SYSTEM
C NUM                    NUMBER OF ELEMENT CURRENTLY BEING TREATED
C NUSE                   VALUE OF NUM FOR REFERENCE TO BEAM LINE BEING USED
C NDIF                   INCREMENT FOR CURRENT ELEMENT NUMBER
C I                      POINTER TO ELEMENT DATA
C
      INTEGER         NEL, NUM, NUSE, NDIF, I
C
      COMMON /DATA2A/ NEL, NUM, NUSE, NDIF, I