func TestEquivalent(t *testing.T) {
t.Parallel()
elements := []set.Element{"A", "B", "C", "D", "E", "F"}
A := set.WithElements(elements...)
B := set.WithElements(elements...)
if !set.Equivalent(A, B) {
t.Fatalf("%s and %s should be equivalent", A, B)
}
if set.Equivalent(A, set.Empty) {
t.Fatalf("%s and %s should not be equivalent", A, set.Empty)
}
if !set.Equivalent(set.Empty, set.Empty) {
t.Fatalf("%s and %s should be equivalent", set.Empty, set.Empty)
}
}
func TestString(t *testing.T) {
t.Parallel()
A := set.WithElements(1, 2, 3)
B := set.Clone(A)
if !set.Equivalent(A, B) {
t.Fatalf("Clone of %s: %s should be equivalent", A, B)
}
B.Remove(1)
if set.Equivalent(A, B) {
t.Fatalf("%s should no longer be equivalent to %s", B, A)
}
if !A.Contains(1) {
t.Fatalf("%s should still contain 1", A)
}
}
func TestSetComplement(t *testing.T) {
t.Parallel()
A := set.WithElements(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
B := set.WithElements(2, 4, 6, 8, 10)
Odds := set.Complement(A, B)
expectedOdds := set.WithElements(1, 3, 5, 7, 9)
if !set.Equivalent(Odds, expectedOdds) {
t.Fatalf("Expected %s\\%s to be %s, but got %s", A, B, expectedOdds, Odds)
}
}
// ComposableRelations indicates whether the list of relations can be
// composed. That is to say whether they are defined over equivalent Universes.
func ComposableRelations(relations []AbstractInterface) bool {
if len(relations) == 0 {
return true
}
u := relations[0].Universe()
for _, b := range relations {
if !set.Equivalent(u, b.Universe()) {
return false
}
}
return true
}
func TestSetIntersection(t *testing.T) {
t.Parallel()
A := set.WithElements("one", "two")
B := set.WithElements("two", "three")
I := set.Intersection(A, B)
if I.Cardinality() != 1 {
t.Fatalf("Intersection of %s and %s should have cardinality 1", A, B)
}
expected := set.WithElements("two")
if !set.Equivalent(I, expected) {
t.Fatalf("Expected %s intersect %s to be %s, but got %s", A, B, expected, I)
}
}
// Compose takes two distributions, p and q, and creates a third lottery,
// n which takes on each outcome in p with a probability alpha times that
// events previous probability and each event in q with a probability 1-alpha
// times that events previous probability.
//
// for o ∈ p.Domain() intersect q.Domain(); P(x in n) is alpha*P(x in p) + (1-alpha)P(x in q)
func Compose(p, q DiscreteDistribution, alpha Probability) DiscreteDistribution {
assert(FullySupported(p), "first distribution is not fully supported")
assert(FullySupported(q), "second distribution is not fully supported")
assert(set.Equivalent(p.Domain(), q.Domain()), "domains of both distributions must be equivalent")
n := NewDiscreteDistribution(p.Domain())
for o := range n.Domain().Iter() {
cp := alpha*p.ProbabilityOf(o) + (1-alpha)*q.ProbabilityOf(o)
if cp == Impossible {
continue // don't bother supporting
}
n.AddOutcome(o, cp)
}
return n
}
