This predicate is offered in CLP(R) only. It computes the infimum of
Expression within the current constraint store, with the
additional constraint that in that infimum, all variables in Ints
have integral values. Vertex will contain the values of Ints
in the infimum. Eps denotes how much a value may differ from
an integer to be considered an integer. E.g. when
Eps = 0.001, then X = 4.999 will be considered as an integer
(5 in this case). Eps should be between 0 and 0.5.