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// Copyright ©2012 The bíogo Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package kdtree
import (
"math/rand"
"sort"
"testing"
"gopkg.in/check.v1"
)
type Ints []int
func (a Ints) Len() int { return len(a) }
func (a Ints) Less(i, j int) bool { return a[i] < a[j] }
func (a Ints) Slice(s, e int) SortSlicer { return a[s:e] }
func (a Ints) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
func (s *S) TestPartition(c *check.C) {
for p := 0; p < 100; p++ {
list := make(Ints, 1e5)
for i := range list {
list[i] = rand.Int()
}
pi := Partition(list, rand.Intn(list.Len()))
for i := 0; i < pi; i++ {
c.Check(list[i] <= list[pi], check.Equals, true)
}
for i := pi + 1; i < len(list); i++ {
c.Check(list[i] > list[pi], check.Equals, true)
}
}
}
func (s *S) TestPartitionCollision(c *check.C) {
for p := 0; p < 10; p++ {
list := make(Ints, 10)
for i := range list {
list[i] = rand.Intn(5)
}
pi := Partition(list, p)
for i := 0; i < pi; i++ {
c.Check(list[i] <= list[pi], check.Equals, true)
}
for i := pi + 1; i < len(list); i++ {
c.Check(list[i] > list[pi], check.Equals, true)
}
}
}
func sortSelection(list Ints, k int) int {
sort.Sort(list)
return list[k]
}
func (s *S) TestSelect(c *check.C) {
for k := 0; k < 2121; k++ {
list := make(Ints, 2121)
for i := range list {
list[i] = rand.Intn(1000)
}
Select(list, k)
sorted := append(Ints(nil), list...)
c.Check(list[k], check.Equals, sortSelection(sorted, k), check.Commentf("\n%d\n%v\n%v", k, list, sorted))
}
}
func (s *S) TestMedianOfMedians(c *check.C) {
list := make(Ints, 1e4)
for i := range list {
list[i] = rand.Int()
}
p := MedianOfMedians(list)
med := list[p]
sort.Sort(list)
var found bool
for _, v := range list[len(list)*3/10 : len(list)*7/10+1] {
if v == med {
found = true
break
}
}
c.Check(found, check.Equals, true)
}
func (s *S) TestMedianOfRandoms(c *check.C) {
list := make(Ints, 1e4)
for i := range list {
list[i] = rand.Int()
}
p := MedianOfRandoms(list, Randoms)
med := list[p]
sort.Sort(list)
var found bool
for _, v := range list[len(list)*3/10 : len(list)*7/10+1] {
if v == med {
found = true
break
}
}
c.Check(found, check.Equals, true)
}
func BenchmarkMoM(b *testing.B) {
for i := 0; i < b.N; i++ {
b.StopTimer()
list := make(Ints, 1e4)
for i := range list {
list[i] = rand.Int()
}
b.StartTimer()
_ = MedianOfMedians(list)
}
}
func BenchmarkMoMPartition(b *testing.B) {
for i := 0; i < b.N; i++ {
b.StopTimer()
list := make(Ints, 1e4)
for i := range list {
list[i] = rand.Int()
}
b.StartTimer()
p := MedianOfMedians(list)
p = Partition(list, p)
}
}
func BenchmarkRM(b *testing.B) {
b.StopTimer()
list := make(Ints, 1e4)
for i := range list {
list[i] = rand.Int()
}
b.StartTimer()
for i := 0; i < b.N; i++ {
_ = MedianOfRandoms(list, list.Len()/1e3)
}
}
func BenchmarkRMPartition(b *testing.B) {
b.StopTimer()
list := make(Ints, 1e4)
for i := range list {
list[i] = rand.Int()
}
b.StartTimer()
for i := 0; i < b.N; i++ {
p := MedianOfRandoms(list, list.Len()/1e3)
p = Partition(list, p)
}
}
func BenchmarkSM(b *testing.B) {
for i := 0; i < b.N; i++ {
b.StopTimer()
list := make(Ints, 1e4)
for i := range list {
list[i] = rand.Int()
}
b.StartTimer()
sort.Sort(list)
}
}
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