func TestUtilityBinaryRelation(t *testing.T) {
s := set.New()
s.Add("one")
s.Add("two")
s.Add("three")
ub := NewUtilityBinaryRelationOn(s, u)
if !relation.Reflexive(ub) {
t.Errorf("Our UtilityBinaryRelation should be reflexive")
}
if !relation.Complete(ub) {
t.Errorf("Our UtilityBinaryRelation should be complete")
}
if !relation.Transitive(ub) {
t.Errorf("Our UtilityBinaryRelation should be transitive")
}
if !Rational(Preference(ub)) {
t.Errorf("Our UtilityBinaryRelation should be rational! -- von Neumann-Morgenstern")
}
}
func TestBinaryRelationBasicUsage(t *testing.T) {
s := set.WithElements(1, 2, 3, 4, 5, 6, 7, 8, 9, 0)
b := relation.New(s)
if b.Universe() != s {
t.Errorf("Expected b's universe to be the set given in constructoon")
}
// Let's define the greater than binary relation
b.AddRelation(2, 1)
b.AddRelation(3, 2)
b.AddRelation(4, 3)
b.AddRelation(5, 4)
b.AddRelation(6, 5)
b.AddRelation(7, 6)
b.AddRelation(8, 7)
b.AddRelation(9, 8)
b.AddRelation(1, 0)
if !b.ContainsRelation(3, 2) {
t.Error("Expected the binary relation to contain (3, 2), as we defined it")
}
if relation.Complete(b) {
t.Error("Expected b to be incomplete, consider: (9, 0)")
}
if !b.ContainsRelation(1, 0) {
t.Errorf("Expected binary relation to contain (1, 0")
}
b.RemoveRelation(1, 0)
if b.ContainsRelation(1, 0) {
t.Errorf("Expected binary relation to no longer contain (1, 0), as we removed it")
}
}