写一个matlab代码，真的不会

用牛顿迭代法造立方根表，令x等于三次根号下a，a=42002210621

https://zhidao.baidu.com/question/503616093974431564/answer/3384104165.html

float CubeRoot(float num)
{
    float x = num;
    float error = 1e-5;
    
    while (fabs(num - (x * x * x)) >= error)
    {
        x = (2 * x + num / (x * x)) / 3.0;
    }
    
    return x;
}