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// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// A copy of Sqrt tests from the math package to test the
// purely integer arithmetic implementation in sqrt.go.
package runtime_test
import (
"math"
"runtime"
"testing"
)
func SqrtRT(x float64) float64 {
return math.Float64frombits(runtime.Sqrt(math.Float64bits(x)))
}
func TestSqrt(t *testing.T) {
for i := 0; i < len(vf); i++ {
a := math.Abs(vf[i])
if f := SqrtRT(a); sqrt[i] != f {
t.Errorf("Sqrt(%g) = %g, want %g", a, f, sqrt[i])
}
}
for i := 0; i < len(vfsqrtSC); i++ {
if f := SqrtRT(vfsqrtSC[i]); !alike(sqrtSC[i], f) {
t.Errorf("Sqrt(%g) = %g, want %g", vfsqrtSC[i], f, sqrtSC[i])
}
}
}
func alike(a, b float64) bool {
switch {
case math.IsNaN(a) && math.IsNaN(b):
return true
case a == b:
return math.Signbit(a) == math.Signbit(b)
}
return false
}
var vf = []float64{
4.9790119248836735e+00,
7.7388724745781045e+00,
-2.7688005719200159e-01,
-5.0106036182710749e+00,
9.6362937071984173e+00,
2.9263772392439646e+00,
5.2290834314593066e+00,
2.7279399104360102e+00,
1.8253080916808550e+00,
-8.6859247685756013e+00,
}
var sqrt = []float64{
2.2313699659365484748756904e+00,
2.7818829009464263511285458e+00,
5.2619393496314796848143251e-01,
2.2384377628763938724244104e+00,
3.1042380236055381099288487e+00,
1.7106657298385224403917771e+00,
2.286718922705479046148059e+00,
1.6516476350711159636222979e+00,
1.3510396336454586262419247e+00,
2.9471892997524949215723329e+00,
}
var vfsqrtSC = []float64{
math.Inf(-1),
-math.Pi,
math.Copysign(0, -1),
0,
math.Inf(1),
math.NaN(),
math.Float64frombits(2),
}
var sqrtSC = []float64{
math.NaN(),
math.NaN(),
math.Copysign(0, -1),
0,
math.Inf(1),
math.NaN(),
3.1434555694052576e-162,
}
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