Parameters

 Keyword  Position  Type        Description
 -------  --------  ----        -----------
 MODEL       -      UNIV        Data object containing fit
                                model.
           GLOBAL.FIT_MODEL (Default model dataset)
 NUM         1      CHAR        List of ties to operate on (either in
   Default = *                  in SHOW or CANCEL modes
 PARS        2      CHAR        Constraint string. Currently just a
                                list of parameters for equality constraint
 ADD         -      LOGICAL     Add a new tie?
   Default = NO
 SHOW        -      LOGICAL     Display ties
   Default = NO
 CANCEL      -      LOGICAL     Delete a tie
   Default = NO