removed PointMinHeap and PointMaxHeap

Author: yuzhichang

point.go

@@ -4,6 +4,7 @@ import (
 	"encoding/binary"
 	"sort"
 
+	datastructures "github.com/deepfabric/go-datastructures"
 	"github.com/keegancsmith/nth"
 )
 
@@ -12,12 +13,6 @@ type Point struct {
 	UserData uint64
 }
 
-// PointMinHeap is a min-heap of points.
-type PointMinHeap []Point
-
-// PointMaxHeap is a max-heap of points.
-type PointMaxHeap []Point
-
 type PointArray interface {
 	sort.Interface
 	GetPoint(idx int) Point
@@ -41,6 +36,17 @@ type PointArrayExt struct {
 	pointSize   int
 }
 
+// Compare is part of datastructures.Comparable interface
+func (p Point) Compare(other datastructures.Comparable) int {
+	rhs := other.(Point)
+	for dim := 0; dim < len(p.Vals); dim++ {
+		if p.Vals[dim] != rhs.Vals[dim] {
+			return int(p.Vals[dim] - rhs.Vals[dim])
+		}
+	}
+	return int(p.UserData - rhs.UserData)
+}
+
 func (p *Point) Inside(lowPoint, highPoint Point) (isInside bool) {
 	for dim := 0; dim < len(p.Vals); dim++ {
 		if p.Vals[dim] < lowPoint.Vals[dim] || p.Vals[dim] > highPoint.Vals[dim] {
@@ -111,68 +117,6 @@ func (p *Point) Decode(b []byte, numDims int, bytesPerDim int) {
 	return
 }
 
-// Len is part of sort.Interface.
-func (s PointMinHeap) Len() int {
-	return len(s)
-}
-
-// Swap is part of sort.Interface.
-func (s PointMinHeap) Swap(i, j int) {
-	s[i], s[j] = s[j], s[i]
-}
-
-// Less is part of sort.Interface.
-func (s PointMinHeap) Less(i, j int) bool {
-	return s[i].LessThan(s[j])
-}
-
-// Push is part of heap.Interface.
-func (s *PointMinHeap) Push(x interface{}) {
-	// Push and Pop use pointer receivers because they modify the slice's length,
-	// not just its contents.
-	*s = append(*s, x.(Point))
-}
-
-// Pop is part of heap.Interface.
-func (s *PointMinHeap) Pop() interface{} {
-	old := *s
-	n := len(old)
-	x := old[n-1]
-	*s = old[0 : n-1]
-	return x
-}
-
-// Len is part of sort.Interface.
-func (s PointMaxHeap) Len() int {
-	return len(s)
-}
-
-// Swap is part of sort.Interface.
-func (s PointMaxHeap) Swap(i, j int) {
-	s[i], s[j] = s[j], s[i]
-}
-
-// Less is part of sort.Interface.
-func (s PointMaxHeap) Less(i, j int) bool {
-	return s[j].LessThan(s[i])
-}
-
-// Push is part of heap.Interface.
-func (s *PointMaxHeap) Push(x interface{}) {
-	// Push and Pop use pointer receivers because they modify the slice's length,
-	// not just its contents.
-	*s = append(*s, x.(Point))
-}
-
-// Pop is part of heap.Interface.
-func (s *PointMaxHeap) Pop() interface{} {
-	old := *s
-	n := len(old)
-	x := old[n-1]
-	*s = old[0 : n-1]
-	return x
-}
-
 // Len is part of sort.Interface.
 func (s *PointArrayMem) Len() int {
 	return len(s.points)

point_test.go

@@ -2,15 +2,9 @@ package bkdtree
 
 import (
 	"bytes"
-	"container/heap"
-	"fmt"
 	"math/rand"
 	"os"
 	"testing"
-
-	"sort"
-
-	"github.com/juju/testing/checkers"
 )
 
 type CaseInside struct {
@@ -101,72 +95,6 @@ func NewRandPoints(numDims int, maxVal uint64, size int) (points []Point) {
 	return
 }
 
-func TestPointHeap(t *testing.T) {
-	numDims := 3
-	maxVal := uint64(100)
-	size := 10000
-	points := NewRandPoints(numDims, maxVal, size)
-	/*There are several ways to build a heap from array:
-
-	s := PointMinHeap(points)
-	h := &s
-	heap.Init(h)
-
-	h := &PointMinHeap{}
-	*h = points
-	heap.Init(h)
-
-	s := &points
-	h := (*PointMinHeap)(s)
-	heap.Init(h)
-
-	h := &PointMinHeap{}
-	for i := 0; i < len(points); i++ {
-		heap.Push(h, points[i])
-	}
-	*/
-	h := &PointMinHeap{}
-	*h = points
-	heap.Init(h)
-	var prevPoint *Point
-	var smallestN1 []Point
-	var smallestN2 []Point
-	N := 1000
-	for h.Len() > 0 {
-		p := heap.Pop(h).(Point)
-		if prevPoint != nil && p.LessThan(*prevPoint) {
-			t.Fatalf("incorrect order of %v %v", *prevPoint, p)
-		}
-		prevPoint = &p
-		if len(smallestN1) < N {
-			smallestN1 = append(smallestN1, p)
-		}
-	}
-
-	/*Inspired by https://stackoverflow.com/questions/5845810/constant-size-priority-queue-insert-first-or-delete-first
-	h2 is a max-heap which stores the N smallest points found so far. The top (largest) is at index zero.
-	*/
-	h2 := &PointMaxHeap{}
-	heap.Init(h2)
-	for i := 0; i < len(points); i++ {
-		if len(*h2) < N {
-			h2.Push(points[i])
-		} else if points[i].LessThan((*h2)[0]) {
-			(*h2)[0] = points[i]
-			heap.Fix(h2, 0)
-		}
-	}
-	s := PointMinHeap(*h2)
-	sort.Sort(&s)
-	smallestN2 = s
-	isEqual, err := checkers.DeepEqual(smallestN1, smallestN2)
-	if !isEqual {
-		fmt.Printf("smallestN1: %+v\n", smallestN1)
-		fmt.Printf("smallestN2: %+v\n", smallestN2)
-		t.Fatalf("smallestN1 and smallestN2 %+v", err)
-	}
-}
-
 func TestPointArrayExt_ToMem(t *testing.T) {
 	numDims := 3
 	maxVal := uint64(100)