A Tour of Go : Advanced Exercise: Complex cube roots

A Tour of Go系列。如有问题欢迎指出~

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这个也没什么好说的，就是试一下内建的复数运算。

Let's explore Go's built-in support for complex numbers via thecomplex64 and complex128 types. For cube roots, Newton's method amounts to repeating:

Find the cube root of 2, just to make sure the algorithm works. There is aPow function in the math/cmplx package.

代码:

package main

import (
    "fmt"
    "math/cmplx"
)

func Cbrt(x complex128) complex128 {
    z:=complex128(1)
    for i:=0;i<10;i++{
        z=z-(z*z*z-x)/(3*z*z)
    }
    return z
}

func main() {
    fmt.Println(Cbrt(2))
    fmt.Println(cmplx.Pow(2,1.0/3))
}

将输出：

(1.2599210498948732+0i)
(1.259921049894873+0i)

注意一下cmplx.Pow的用法。