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:

 1 package main

 2 

 3 import (

 4     "fmt"

 5     "math/cmplx"

 6 )

 7 

 8 func Cbrt(x complex128) complex128 {

 9     z:=complex128(1)

10     for i:=0;i<10;i++{

11         z=z-(z*z*z-x)/(3*z*z)

12     }

13     return z

14 }

15 

16 func main() {

17     fmt.Println(Cbrt(2))

18     fmt.Println(cmplx.Pow(2,1.0/3))

19 }

将输出：

(1.2599210498948732+0i)

(1.259921049894873+0i)

注意一下cmplx.Pow的用法。