3.7.209. Reified constraint
The reified version of a given constraint , where has as arguments all arguments of plus one extra 0-1 variable. This 0-1 variable is set to 1 when constraint holds, and 0 otherwise. Note that constraint inherits from all restrictions of constraint (i.e., incorrect parameters for constraint are also incorrect for constraint ). Within the context of linear programming the extra 0-1 variable is often called an indicator variable.
It was shown in Β [BeldiceanuCarlssonFlenerPearson12] how to reify a global constraint by reformulating it as a conjunction of pure functional dependency constraints together with a constraint that can be easily reified (e.g., an automaton with or without counter, or a Boolean combination of linear arithmetic equalities and inequalities and 0-1 variables).