打印一個ref變量

Question

我負責打印一組數字的一組數字的平均值和方差，並且我需要對我所做的平均值做一個參考。但我不明白我現在可以打印什麼樣的平均值。當我運行程序時，我正在打印0。這是我的代碼：

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

你在這一點上打印爲零，因爲數組是空的，當你調用

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

首先調用方差函數w /陣列PARAMS（這也將設置AVG）。然後自己調用平均值。

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(); 
}