SKREEX    SKREEX    SKREEX    SKREEX    SKREEX    SKREEX    SKREEX    
          **********************************************
                    **************************
                              ******

SUBROUTINE SKREEX (IR, ISKWRK, RSKWRK, RE)

Returns the activation energy
of the IRth reaction, or changes its
value, depending on the sign of IR.

INPUT
IR        - Integer scalar, reaction index;
            IR> 0 gets RE(I) from RSKWRK
            IR< 0 puts RE(I) into RSKWRK
ISKWRK(*) - Integer workspace array; dimension at least LENISK.
RSKWRK(*) - Real    workspace array; dimension at least LENRSK.

If IR< 0:
RE        - Real scalar, activation energy for
            reaction IR.
               cgs units, K

OUTPUT
If IR> 0:
RE        - Real scalar, activation energy for
            reaction IR.
               cgs units, K