math: add functions Log2, Nextafter, Fdim, Fmax, Fmin
Add functions, tests and benchmarks. Fix typos in comments
in expm1 and hypot_386. Fix Acosh domain error in benchmark
test.
R=rsc
CC=golang-dev
https://golang.org/cl/204069
diff --git a/src/pkg/math/all_test.go b/src/pkg/math/all_test.go
index 184d045..8c47fd1 100644
--- a/src/pkg/math/all_test.go
+++ b/src/pkg/math/all_test.go
@@ -208,6 +208,18 @@
1.842068661871398836913874273e-02,
-8.3193870863553801814961137573e-02,
}
+var fdim = []float64{
+ 4.9790119248836735e+00,
+ 7.7388724745781045e+00,
+ 0.0000000000000000e+00,
+ 0.0000000000000000e+00,
+ 9.6362937071984173e+00,
+ 2.9263772392439646e+00,
+ 5.2290834314593066e+00,
+ 2.7279399104360102e+00,
+ 1.8253080916808550e+00,
+ 0.0000000000000000e+00,
+}
var floor = []float64{
4.0000000000000000e+00,
7.0000000000000000e+00,
@@ -287,6 +299,18 @@
1.8088493239630770262045333e-02,
-9.0865245631588989681559268e-02,
}
+var log2 = []float64{
+ 2.3158594707062190618898251e+00,
+ 2.9521233862883917703341018e+00,
+ -1.8526669502700329984917062e+00,
+ 2.3249844127278861543568029e+00,
+ 3.268478366538305087466309e+00,
+ 1.5491157592596970278166492e+00,
+ 2.3865580889631732407886495e+00,
+ 1.447811865817085365540347e+00,
+ 8.6813999540425116282815557e-01,
+ 3.118679457227342224364709e+00,
+}
var modf = [][2]float64{
[2]float64{4.0000000000000000e+00, 9.7901192488367350108546816e-01},
[2]float64{7.0000000000000000e+00, 7.3887247457810456552351752e-01},
@@ -299,6 +323,18 @@
[2]float64{1.0000000000000000e+00, 8.2530809168085506044576505e-01},
[2]float64{-8.0000000000000000e+00, -6.8592476857560136238589621e-01},
}
+var nextafter = []float64{
+ 4.97901192488367438926388786e+00,
+ 7.73887247457810545370193722e+00,
+ -2.7688005719200153853520874e-01,
+ -5.01060361827107403343006808e+00,
+ 9.63629370719841915615688777e+00,
+ 2.92637723924396508934364647e+00,
+ 5.22908343145930754047867595e+00,
+ 2.72793991043601069534929593e+00,
+ 1.82530809168085528249036997e+00,
+ -8.68592476857559958602905681e+00,
+}
var pow = []float64{
9.5282232631648411840742957e+04,
5.4811599352999901232411871e+07,
@@ -706,6 +742,17 @@
[2]float64{NaN(), NaN()},
}
+var vfnextafterSC = [][2]float64{
+ [2]float64{0, NaN()},
+ [2]float64{NaN(), 0},
+ [2]float64{NaN(), NaN()},
+}
+var nextafterSC = []float64{
+ NaN(),
+ NaN(),
+ NaN(),
+}
+
var vfpowSC = [][2]float64{
[2]float64{-Pi, Pi},
[2]float64{-Pi, -Pi},
@@ -1031,6 +1078,14 @@
}
}
+func TestFdim(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Fdim(vf[i], 0); fdim[i] != f {
+ t.Errorf("Fdim(%g, %g) = %g, want %g\n", vf[i], 0.0, f, fdim[i])
+ }
+ }
+}
+
func TestFloor(t *testing.T) {
for i := 0; i < len(vf); i++ {
if f := Floor(vf[i]); floor[i] != f {
@@ -1044,6 +1099,22 @@
}
}
+func TestFmax(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Fmax(vf[i], ceil[i]); ceil[i] != f {
+ t.Errorf("Fmax(%g, %g) = %g, want %g\n", vf[i], ceil[i], f, ceil[i])
+ }
+ }
+}
+
+func TestFmin(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Fmin(vf[i], floor[i]); floor[i] != f {
+ t.Errorf("Fmin(%g, %g) = %g, want %g\n", vf[i], floor[i], f, floor[i])
+ }
+ }
+}
+
func TestFmod(t *testing.T) {
for i := 0; i < len(vf); i++ {
if f := Fmod(10, vf[i]); fmod[i] != f { /*!close(fmod[i], f)*/
@@ -1149,6 +1220,23 @@
}
}
+func TestLog2(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Fabs(vf[i])
+ if f := Log2(a); !veryclose(log2[i], f) {
+ t.Errorf("Log2(%g) = %g, want %g\n", a, f, log2[i])
+ }
+ }
+ if f := Log2(E); f != Log2E {
+ t.Errorf("Log2(%g) = %g, want %g\n", E, f, Log2E)
+ }
+ for i := 0; i < len(vflogSC); i++ {
+ if f := Log2(vflogSC[i]); !alike(logSC[i], f) {
+ t.Errorf("Log2(%g) = %g, want %g\n", vflogSC[i], f, logSC[i])
+ }
+ }
+}
+
func TestModf(t *testing.T) {
for i := 0; i < len(vf); i++ {
if f, g := Modf(vf[i]); !veryclose(modf[i][0], f) || !veryclose(modf[i][1], g) {
@@ -1162,6 +1250,19 @@
}
}
+func TestNextafter(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Nextafter(vf[i], 10); nextafter[i] != f {
+ t.Errorf("Nextafter(%g, %g) = %g want %g\n", vf[i], 10.0, f, nextafter[i])
+ }
+ }
+ for i := 0; i < len(vfmodfSC); i++ {
+ if f := Nextafter(vfnextafterSC[i][0], vfnextafterSC[i][1]); !alike(nextafterSC[i], f) {
+ t.Errorf("Nextafter(%g, %g) = %g want %g\n", vfnextafterSC[i][0], vfnextafterSC[i][1], f, nextafterSC[i])
+ }
+ }
+}
+
func TestPow(t *testing.T) {
for i := 0; i < len(vf); i++ {
if f := Pow(10, vf[i]); !close(pow[i], f) {
@@ -1309,7 +1410,7 @@
func BenchmarkAcosh(b *testing.B) {
for i := 0; i < b.N; i++ {
- Acosh(.5)
+ Acosh(1.5)
}
}
@@ -1397,6 +1498,24 @@
}
}
+func BenchmarkFdim(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ Fdim(10, 3)
+ }
+}
+
+func BenchmarkFmax(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ Fmax(10, 3)
+ }
+}
+
+func BenchmarkFmin(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ Fmin(10, 3)
+ }
+}
+
func BenchmarkFmod(b *testing.B) {
for i := 0; i < b.N; i++ {
Fmod(10, 3)
@@ -1439,12 +1558,24 @@
}
}
+func BenchmarkLog2(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ Log2(.5)
+ }
+}
+
func BenchmarkModf(b *testing.B) {
for i := 0; i < b.N; i++ {
Modf(1.5)
}
}
+func BenchmarkNextafter(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ Nextafter(.5, 1)
+ }
+}
+
func BenchmarkPowInt(b *testing.B) {
for i := 0; i < b.N; i++ {
Pow(2, 2)
