Added Atan2{,32}.

math.go

@@ -19,16 +19,26 @@ func Abs32(f float32) float32 {
 	return float32(Abs(float64(f)))
 }
 
-// Atan returns the arctangent of f.
+// Atan returns the arc tangent of f.
 func Atan(f float64) float64 {
 	return math.Atan(f)
 }
 
-// Atan32 returns the arctangent of f.
+// Atan2 returns the arc tangent of y/x.
+func Atan2(y, x float64) float64 {
+	return math.Atan2(y, x)
+}
+
+// Atan32 returns the arc tangent of f.
 func Atan32(f float32) float32 {
 	return float32(math.Atan(float64(f)))
 }
 
+// Atan232 returns the arc tangent of y/x.
+func Atan232(y, x float32) float32 {
+	return float32(math.Atan2(float64(y), float64(x)))
+}
+
 // Ceil rounds f up to an natural number.
 func Ceil(f float64) float64 {
 	return math.Ceil(f)