Exercise 47 (Complex Cube Root) from tour.golang.org

47_complex_cube_root.go

package main

import "fmt"
import "math/cmplx"

// #47, Complex cube roots
// Cbrt returns a complex128 that is the cube
// root of its lone argument
func Cbrt(x complex128) complex128 {
  z := 1.0 + 0i
	for i := 0; i < 20; i++ {
		z -= (cmplx.Pow(z, 3) - x) / (3 * z * z)
	}
	return z
}

func main() {
	fmt.Println(Cbrt(2))
}