feat: move new functions from v2 version

mathutil/mathutil.go

@@ -90,3 +90,39 @@ func TruncRound(x float64, n int) float64 {
 	res, _ := strconv.ParseFloat(newFloat, 64)
 	return res
 }
+
+// AngleToRadian converts angle value to radian value.
+func AngleToRadian(angle float64) float64 {
+	radian := angle * (math.Pi / 180)
+	return radian
+}
+
+// RadianToAngle converts radian value to angle value.
+func RadianToAngle(radian float64) float64 {
+	angle := radian * (180 / math.Pi)
+	return angle
+}
+
+// PointDistance get two points distance.
+func PointDistance(x1, y1, x2, y2 float64) float64 {
+	a := x1 - x2
+	b := y1 - y2
+	c := math.Pow(a, 2) + math.Pow(b, 2)
+
+	return math.Sqrt(c)
+}
+
+// IsPrimes checks if number is prime number.
+func IsPrime(n int) bool {
+	if n < 2 {
+		return false
+	}
+
+	for i := 2; i <= int(math.Sqrt(float64(n))); i++ {
+		if n%i == 0 {
+			return false
+		}
+	}
+
+	return true
+}

mathutil/mathutil_test.go

@@ -1,6 +1,7 @@
 package mathutil
 
 import (
+	"math"
 	"testing"
 
 	"github.com/duke-git/lancet/internal"
@@ -70,3 +71,46 @@ func TestTruncRound(t *testing.T) {
 	assert.Equal(TruncRound(0.125, 3), float64(0.125))
 	assert.Equal(TruncRound(33.33333, 2), float64(33.33))
 }
+
+func TestAngleToRadian(t *testing.T) {
+	assert := internal.NewAssert(t, "TestAngleToRadian")
+
+	result1 := AngleToRadian(45)
+	result2 := AngleToRadian(90)
+	result3 := AngleToRadian(180)
+
+	assert.Equal(0.7853981633974483, result1)
+	assert.Equal(1.5707963267948966, result2)
+	assert.Equal(3.141592653589793, result3)
+}
+
+func TestRadianToAngle(t *testing.T) {
+	assert := internal.NewAssert(t, "TestAngleToRadian")
+
+	result1 := RadianToAngle(math.Pi)
+	result2 := RadianToAngle(math.Pi / 2)
+	result3 := RadianToAngle(math.Pi / 4)
+
+	assert.Equal(float64(180), result1)
+	assert.Equal(float64(90), result2)
+	assert.Equal(float64(45), result3)
+}
+
+func TestPointDistance(t *testing.T) {
+	assert := internal.NewAssert(t, "TestPointDistance")
+
+	result1 := PointDistance(1, 1, 4, 5)
+
+	assert.Equal(float64(5), result1)
+}
+
+func TestIsPrime(t *testing.T) {
+	assert := internal.NewAssert(t, "TestIsPrime")
+
+	assert.Equal(false, IsPrime(-1))
+	assert.Equal(false, IsPrime(0))
+	assert.Equal(false, IsPrime(1))
+	assert.Equal(true, IsPrime(2))
+	assert.Equal(true, IsPrime(3))
+	assert.Equal(false, IsPrime(4))
+}