complex: use real pow on real only complex to gain precision

1 files changed, 15 insertions, 15 deletions

diff --git a/src/complex.rs b/src/complex.rs
index d120c29..5b95df4 100644
--- a/src/complex.rs
+++ b/src/complex.rs
@@ -1,6 +1,6 @@
+use std::f64::consts::E;
 use std::num::ParseFloatError;
 use std::str::FromStr;
-use std::f64::consts::E;
 
 #[derive(Clone, Copy, Default, Debug)]
 pub struct Complex {
@@ -13,12 +13,8 @@ impl Complex {
         Self { real, imag }
     }
 
-    pub fn div(&mut self, other: &Self) {
-        let z = other.real * other.real + other.imag * other.imag;
-        self.real = self.real * other.real + self.imag * other.imag;
-        self.real /= z;
-        self.imag = self.imag * other.real - self.real * other.imag;
-        self.imag /= z;
+    pub fn is_real(&self) -> bool {
+        self.imag == 0.0
     }
 
     pub fn abs(&self) -> f64 {
@@ -26,12 +22,16 @@ impl Complex {
     }
 
     pub fn pow(&self, rhs: Self) -> Self {
-        let r = self.abs();
-        let x = (self.imag / self.real).atan();
-        let lnr = r.ln();
-        let alpha = lnr * rhs.imag + x * rhs.real;
-        let e_exp = E.powf(lnr * rhs.real - rhs.imag * x);
-        Complex::new(e_exp * alpha.cos(), e_exp * alpha.sin())
+        if self.is_real() && rhs.is_real() {
+            Complex::new(self.real.powf(rhs.real), 0.0)
+        } else {
+            let r = self.abs();
+            let x = (self.imag / self.real).atan();
+            let lnr = r.ln();
+            let alpha = lnr * rhs.imag + x * rhs.real;
+            let e_exp = E.powf(lnr * rhs.real - rhs.imag * x);
+            Complex::new(e_exp * alpha.cos(), e_exp * alpha.sin())
+        }
     }
 
     pub fn sqrt(&self) -> Self {
@@ -39,14 +39,14 @@ impl Complex {
     }
 
     pub fn cos(&self) -> Self {
-        let e : Complex = E.into();
+        let e: Complex = E.into();
         let i = Complex::new(0.0, 1.0);
 
         Complex::new(e.pow(&i * self).real, 0.0)
     }
 
     pub fn sin(&self) -> Self {
-        let e : Complex = E.into();
+        let e: Complex = E.into();
         let i = Complex::new(0.0, 1.0);
 
         Complex::new(e.pow(&i * self).imag, 0.0)