打印一个ref变量

Question

我负责打印一组数字的一组数字的平均值和方差，并且我需要对我所做的平均值做一个参考。但我不明白我现在可以打印什么样的平均值。当我运行程序时，我正在打印0。这是我的代码：

static double varianceValue(ref double avg, params double[] intValues) 
    { 
     double sum = 0; 
     double f = 0; 
     double number = 0; 
     double sv = 0; 
     double variance= 0; 

     foreach (int value in intValues) 
     { 
      sum += value; 
     } 

     for (int i = 0; i < intValues.Length; i++) 
     { 
      number = intValues[i]; 
      avg = sum/intValues.Length; 
      f = number - avg; 
      sv += Math.Pow(f, 2); 

     } 
     variance = sv/(intValues.Length - 1); 
     return variance; 

    } 
    static void Main(string[] args) 
    { 
     double avg = 0; 
     Console.WriteLine("The avg of the variables in the array are: {0}", varianceValue(ref avg)); 
     Console.WriteLine("\nThe variance of 11, 13, 17, 19, 23 is: {0}", varianceValue(ref avg, 11.0, 13.0, 17.0, 19.0, 23.0)); 
     Console.ReadKey(); 
    } 

Answer 1

你在这一点上打印为零，因为数组是空的，当你调用

Console.WriteLine("The avg of the variables in the array are: {0}", varianceValue(ref avg)); 

首先调用方差函数w /阵列PARAMS（这也将设置AVG）。然后自己调用平均值。

static void Main(string[] args) 
{ 
    double avg = 0; 
    Console.WriteLine("\nThe variance of 11, 13, 17, 19, 23 is: {0}", varianceValue(ref avg, 11.0, 13.0, 17.0, 19.0, 23.0)); 
    Console.WriteLine("The avg of the variables in the array are: {0}", avg); 
    Console.ReadKey(); 
}