The open interval between a and b is the subposet of P induced by the elements z such that p < z < q. If a and b are incomparable, then an error is thrown.
i1 : P = booleanLattice 3; |
i2 : openInterval(P, "001", "111") o2 = Relation Matrix: | 1 0 | | 0 1 | o2 : Poset |