set: some tweaks

1 files changed, 8 insertions, 7 deletions

diff --git a/skate/set/set.go b/skate/set/set.go
index 29cd3ef..b762cb8 100644
--- a/skate/set/set.go
+++ b/skate/set/set.go
@@ -76,11 +76,11 @@ func (s Set) Intersection(t Set) Set {
 // Union returns the union of two sets.
 func (s Set) Union(t Set) Set {
 	u := New()
-	for _, v := range s.Slice() {
-		u.Add(v)
+	for k := range s {
+		u.Add(k)
 	}
-	for _, v := range t.Slice() {
-		u.Add(v)
+	for k := range t {
+		u.Add(k)
 	}
 	return u
 }
@@ -102,7 +102,7 @@ func (s Set) Sorted() (result []string) {
 	return
 }
 
-// TopK returns at most k elements.
+// TopK returns at most k sorted elements.
 func (s Set) TopK(k int) Set {
 	var top []string
 	for i, v := range s.Sorted() {
@@ -113,7 +113,7 @@ func (s Set) TopK(k int) Set {
 	return FromSlice(top)
 }
 
-// Product returns a slice of pairs, representing the cartesian product.
+// Product returns a slice of pairs, representing the cartesian product of two sets.
 func (s Set) Product(t Set) (result [][]string) {
 	for k := range s {
 		for l := range t {
@@ -123,7 +123,8 @@ func (s Set) Product(t Set) (result [][]string) {
 	return
 }
 
-// Jaccard returns the jaccard index of sets s and t.
+// Jaccard returns the jaccard index of sets s and t, between 0 and 1, where 1
+// means equality.
 func (s Set) Jaccard(t Set) float64 {
 	if s.IsEmpty() && t.IsEmpty() {
 		return 1