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mirror of https://github.com/golang/go synced 2024-11-22 10:54:46 -07:00

casify a few more

R=rsc
DELTA=72  (0 added, 9 deleted, 63 changed)
OCL=22918
CL=22941
This commit is contained in:
Rob Pike 2009-01-16 10:34:21 -08:00
parent 393df07914
commit 4b590bf985
3 changed files with 58 additions and 67 deletions

View File

@ -18,7 +18,7 @@ func min(a, b int) int {
}
// Insertion sort
func InsertionSort(data SortInterface, a, b int) {
func insertionSort(data SortInterface, a, b int) {
for i := a+1; i < b; i++ {
for j := i; j > a && data.Less(j, j-1); j-- {
data.Swap(j, j-1);
@ -30,7 +30,7 @@ func InsertionSort(data SortInterface, a, b int) {
// ``Engineering a Sort Function,'' SP&E November 1993.
// Move the median of the three values data[a], data[b], data[c] into data[a].
func MedianOfThree(data SortInterface, a, b, c int) {
func medianOfThree(data SortInterface, a, b, c int) {
m0 := b;
m1 := a;
m2 := c;
@ -41,22 +41,22 @@ func MedianOfThree(data SortInterface, a, b, c int) {
// now data[m0] <= data[m1] <= data[m2]
}
func SwapRange(data SortInterface, a, b, n int) {
func swapRange(data SortInterface, a, b, n int) {
for i := 0; i < n; i++ {
data.Swap(a+i, b+i);
}
}
func Pivot(data SortInterface, lo, hi int) (midlo, midhi int) {
func doPivot(data SortInterface, lo, hi int) (midlo, midhi int) {
m := (lo+hi)/2;
if hi - lo > 40 {
// Tukey's ``Ninther,'' median of three medians of three.
s := (hi - lo) / 8;
MedianOfThree(data, lo, lo+s, lo+2*s);
MedianOfThree(data, m, m-s, m+s);
MedianOfThree(data, hi-1, hi-1-s, hi-1-2*s);
medianOfThree(data, lo, lo+s, lo+2*s);
medianOfThree(data, m, m-s, m+s);
medianOfThree(data, hi-1, hi-1-s, hi-1-2*s);
}
MedianOfThree(data, lo, m, hi-1);
medianOfThree(data, lo, m, hi-1);
// Invariants are:
// data[lo] = pivot (set up by ChoosePivot)
@ -98,26 +98,26 @@ func Pivot(data SortInterface, lo, hi int) (midlo, midhi int) {
}
n := min(b-a, a-lo);
SwapRange(data, lo, b-n, n);
swapRange(data, lo, b-n, n);
n = min(hi-d, d-c);
SwapRange(data, c, hi-n, n);
swapRange(data, c, hi-n, n);
return lo+b-a, hi-(d-c);
}
func Quicksort(data SortInterface, a, b int) {
func quickSort(data SortInterface, a, b int) {
if b - a > 7 {
mlo, mhi := Pivot(data, a, b);
Quicksort(data, a, mlo);
Quicksort(data, mhi, b);
mlo, mhi := doPivot(data, a, b);
quickSort(data, a, mlo);
quickSort(data, mhi, b);
} else if b - a > 1 {
InsertionSort(data, a, b);
insertionSort(data, a, b);
}
}
export func Sort(data SortInterface) {
Quicksort(data, 0, data.Len());
quickSort(data, 0, data.Len());
}

View File

@ -11,8 +11,6 @@ import (
"testing";
)
func BentleyMcIlroyTests();
var ints = [...]int{74, 59, 238, -784, 9845, 959, 905, 0, 0, 42, 7586, -5467984, 7586}
var floats = [...]float{74.3, 59.0, 238.2, -784.0, 2.3, 9845.768, -959.7485, 905, 7.8, 7.8}
@ -75,7 +73,7 @@ export func TestSortStrings(t *testing.T) {
}
}
export func TestSortLargeRandom(t *testing.T) {
export func TestSortLarge_Random(t *testing.T) {
data := make([]int, 1000000);
for i := 0; i < len(data); i++ {
data[i] = rand.rand() % 100;
@ -90,25 +88,25 @@ export func TestSortLargeRandom(t *testing.T) {
}
const (
Sawtooth = iota;
Rand;
Stagger;
Plateau;
Shuffle;
NDist;
_Sawtooth = iota;
_Rand;
_Stagger;
_Plateau;
_Shuffle;
_NDist;
)
const (
Copy = iota;
Reverse;
ReverseFirstHalf;
ReverseSecondHalf;
Sorted;
Dither;
NMode;
);
_Copy = iota;
_Reverse;
_ReverseFirstHalf;
_ReverseSecondHalf;
_Sorted;
_Dither;
_NMode;
)
type TestingData struct {
type testingData struct {
desc string;
t *testing.T;
data []int;
@ -116,9 +114,9 @@ type TestingData struct {
nswap int;
}
func (d *TestingData) Len() int { return len(d.data); }
func (d *TestingData) Less(i, j int) bool { return d.data[i] < d.data[j]; }
func (d *TestingData) Swap(i, j int) {
func (d *testingData) Len() int { return len(d.data); }
func (d *testingData) Less(i, j int) bool { return d.data[i] < d.data[j]; }
func (d *testingData) Swap(i, j int) {
if d.nswap >= d.maxswap {
d.t.Errorf("%s: used %d swaps sorting array of %d", d.desc, d.nswap, len(d.data));
d.t.FailNow();
@ -127,7 +125,7 @@ func (d *TestingData) Swap(i, j int) {
d.data[i], d.data[j] = d.data[j], d.data[i];
}
func Lg(n int) int {
func lg(n int) int {
i := 0;
for 1<<uint(i) < n {
i++;
@ -135,13 +133,6 @@ func Lg(n int) int {
return i;
}
func Min(a, b int) int {
if a < b {
return a;
}
return b;
}
export func TestBentleyMcIlroy(t *testing.T) {
sizes := []int{100, 1023, 1024, 1025};
dists := []string{"sawtooth", "rand", "stagger", "plateau", "shuffle"};
@ -150,21 +141,21 @@ export func TestBentleyMcIlroy(t *testing.T) {
for ni := 0; ni < len(sizes); ni++ {
n := sizes[ni];
for m := 1; m < 2*n; m *= 2 {
for dist := 0; dist < NDist; dist++ {
for dist := 0; dist < _NDist; dist++ {
j := 0;
k := 1;
data := tmp1[0:n];
for i := 0; i < n; i++ {
switch dist {
case Sawtooth:
case _Sawtooth:
data[i] = i % m;
case Rand:
case _Rand:
data[i] = rand.rand() % m;
case Stagger:
case _Stagger:
data[i] = (i*m + i) % n;
case Plateau:
data[i] = Min(i, m);
case Shuffle:
case _Plateau:
data[i] = min(i, m);
case _Shuffle:
if rand.rand() % m != 0 {
j += 2;
data[i] = j;
@ -176,45 +167,45 @@ export func TestBentleyMcIlroy(t *testing.T) {
}
mdata := tmp2[0:n];
for mode := 0; mode < NMode; mode++ {
for mode := 0; mode < _NMode; mode++ {
switch mode {
case Copy:
case _Copy:
for i := 0; i < n; i++ {
mdata[i] = data[i];
}
case Reverse:
case _Reverse:
for i := 0; i < n; i++ {
mdata[i] = data[n-i-1];
}
case ReverseFirstHalf:
case _ReverseFirstHalf:
for i := 0; i < n/2; i++ {
mdata[i] = data[n/2-i-1];
}
for i := n/2; i < n; i++ {
mdata[i] = data[i];
}
case ReverseSecondHalf:
case _ReverseSecondHalf:
for i := 0; i < n/2; i++ {
mdata[i] = data[i];
}
for i := n/2; i < n; i++ {
mdata[i] = data[n-(i-n/2)-1];
}
case Sorted:
case _Sorted:
for i := 0; i < n; i++ {
mdata[i] = data[i];
}
// sort.SortInts is known to be correct
// because mode Sort runs after mode Copy.
// because mode Sort runs after mode _Copy.
sort.SortInts(mdata);
case Dither:
case _Dither:
for i := 0; i < n; i++ {
mdata[i] = data[i] + i%5;
}
}
desc := fmt.Sprintf("n=%d m=%d dist=%s mode=%s", n, m, dists[dist], modes[mode]);
d := &TestingData{desc, t, mdata[0:n], n*Lg(n)*12/10, 0};
d := &testingData{desc, t, mdata[0:n], n*lg(n)*12/10, 0};
sort.Sort(d);
// If we were testing C qsort, we'd have to make a copy

View File

@ -12,10 +12,10 @@ import (
var chatty = flag.Bool("chatty", false, "chatty")
// Insert tabs after newlines - but not the last one
func Tabify(s string) string {
func tabify(s string) string {
for i := 0; i < len(s) - 1; i++ { // -1 because if last char is newline, don't bother
if s[i] == '\n' {
return s[0:i+1] + "\t" + Tabify(s[i+1:len(s)]);
return s[0:i+1] + "\t" + tabify(s[i+1:len(s)]);
}
}
return s
@ -38,11 +38,11 @@ func (t *T) FailNow() {
}
func (t *T) Log(args ...) {
t.errors += "\t" + Tabify(fmt.Sprintln(args));
t.errors += "\t" + tabify(fmt.Sprintln(args));
}
func (t *T) Logf(format string, args ...) {
t.errors += Tabify(fmt.Sprintf("\t" + format, args));
t.errors += tabify(fmt.Sprintf("\t" + format, args));
l := len(t.errors);
if l > 0 && t.errors[l-1] != '\n' {
t.errors += "\n"
@ -74,7 +74,7 @@ export type Test struct {
f *(*T);
}
func TRunner(t *T, test *Test) {
func tRunner(t *T, test *Test) {
test.f(t);
t.ch <- t;
}
@ -91,7 +91,7 @@ export func Main(tests []Test) {
}
t := new(T);
t.ch = make(chan *T);
go TRunner(t, &tests[i]);
go tRunner(t, &tests[i]);
<-t.ch;
if t.failed {
println("--- FAIL:", tests[i].name);