遇到問題初始化對象的ArrayList構造函數中

Question

大家好我有一個neuralnetwork類，它的構造函數應該初始化：

• 二維雙陣列，雙[在.data文件的行＃] [每行中的數字的＃]
• [每行中的數字]的＃ - 1個InputNodes
• 2/3（向下）* HiddenNodes
• 1輸出節點（其也是HiddenNode對象）＃由需要所有的隱藏節點

什麼我有

• 讓Java創建InputNodes，HiddenNodes和OutputNode自動根據提供的數據麻煩，所以到目前爲止，我有手動創建節點

輸入節點將存儲在數組列表或數組中，然後傳遞給HiddenNode的構造函數參數，HiddenNode只能使用以下參數：

HiddenNode(Node[] nodes) 當一個Node對象是HiddenNode和InputNode的超

這裏是我的代碼到目前爲止我的構造函數：

NeuralNetwork.java

/* 
* These are values for the NeuralNetwork Constructor 
*/ 
private final String comma = ","; 
private final String qMarks = "?"; 
private List<InputNode> input = new ArrayList<InputNode>(); // Input Nodes 
private List<HiddenNode> hiddenNodeLayer = new ArrayList<HiddenNode>(); // ArrayList of HiddenNode[] arrays 
private List<HiddenNode> outputNode = new ArrayList<HiddenNode>(); 

public NeuralNetwork(File f){ 


    try { 
     @SuppressWarnings("resource") 
     Scanner inFile = new Scanner(f); 

     int noOfNodes; 

     //While there is another line in inFile. 
     while (inFile.hasNextLine()){ 
      //Store that line into String line 
      String line = inFile.nextLine(); 
      //System.out.println(line);//Test code to see what the file looks like 
      //Parition values separated by a comma 
      String[] numbers = line.split(comma); 
      //System.out.println(Arrays.toString(columns)); //Test code to see length of each column 
      /*code works and prints out row 
      * */ 
      /* 
      * initialize noOfNodes to length of numbers - 1 
      */ 
      noOfNodes = numbers.length - 1; 

      //Counter for number of rows in .data file 
      int noOfRowsInData = 0; 



      //This will count the number of rows in the .data file 
      LineNumberReader lnr = new LineNumberReader(new FileReader(f)); 
      try { 
       lnr.skip(Long.MAX_VALUE); 
       noOfRowsInData = lnr.getLineNumber(); 
       lnr.close(); 
      } catch (IOException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } 

      data = new double[noOfRowsInData][numbers.length]; 
      //System.out.println(data[0].length); //Test code works properly, and prints numbers.length 

      //Copy over data form the .data file 
      for (int i = 0; i < data.length; i++) { 
       for (int j = 0; j < data[i].length; j++) { 
        // For each row... 
        if (!numbers[j].equals(qMarks)) { 
         // If the values in each row do not equal "?" 
         // Set rows[i] to the values in column[i] 
         data[i][j] = Double.parseDouble(numbers[j]); 
         //System.out.println(data[i][j]); //Test code to see what's printed here 
        } else { 
         data[i][j] = 0; 
         //System.out.println(data[i][j]); //Test code to see what's printed here 
        } 
       } 
      } 
     } 

     //System.out.println(data.length); //See what the length of the data double array is. works 
     //Test code to print out the 2-d double array and see what is being stored 
//   for(int i = 0; i < data.length; i++) { 
//    System.out.println("For Row[" + i + "] of file:"); //Works 
//    for (int j = 0; j < data[i].length; j++) { 
//     System.out.println(" data[" + i + "][" + 
//    j + "] = " + data[i][j]); //Works 
//    } 
//   } 

    } catch (FileNotFoundException e) { 
     // TODO Auto-generated catch block 
     e.printStackTrace(); 
    } 

    //Create 13 InputNode Objects initialized to 0.0 
    for (int n = 0; n < 13; n++){ 
     input[n] = new InputNode(0.0); 
    } 
    //Create 8 HiddenNode objects **HAVING PROBLEMS HERE** 
    for (int o = 0; o < 8; o++){ 
     hiddenNodeLayer.add(new HiddenNode(input)); 
    } 

    System.out.println(hiddenNodeLayer.size() + " HiddenNodes created"); 
    //Create one output Node, which is a hidden node 
    outputNode = new ArrayList<HiddenNode>(1); 
    System.out.println(outputNode.size() + " OutputNode created"); 
} 

更新：的NullPointerException錯誤

獲取這裏一個錯誤：

for (int m = 0; m < noOfNodes; m++){ 
      input[m] = new InputNode(0.0); //NullPointerException error 
     } 
     System.out.println(input.length); 
     //Create 8 HiddenNode objects **HAVING PROBLEMS HERE** 
     int noOfHiddenNodes = (int)Math.floor(2.*noOfNodes/3.); 
     System.out.println(noOfHiddenNodes); 
     for (int o = 0; o < noOfHiddenNodes; o++){ 
      hiddenNodeLayer.add(new HiddenNode(input)); 
     } 

實測值和校正的誤差

我不得不初始化輸入=新InputNode [米]中的for循環中，因爲有沒有InputNodes開頭

for (int m = 0; m < noOfNodes; m++){ 
      input = new InputNode[m]; 
     } 
     System.out.println(input.length + ""); 
     //Create 8 HiddenNode objects **HAVING PROBLEMS HERE** 
     int noOfHiddenNodes = (int)Math.floor(2.*noOfNodes/3.); 
     for (int o = 0; o < noOfHiddenNodes; o++){ 
      hiddenNodeLayer.add(new HiddenNode(input)); 
     } 
     System.out.println(hiddenNodeLayer.size() + " HiddenNodes created"); 
     //Create one output Node, which is a hidden node 
     outputNode = new ArrayList<HiddenNode>(1); 
     System.out.println(outputNode.size() + " OutputNode created"); 

Answer 1

你的意思是這樣嗎？

for (int n = 0; n < noOfNodes; n++){ 
    input[n] = new InputNode(0.0); 
} 
//Create 8 HiddenNode objects **HAVING PROBLEMS HERE** 
int noOfHiddenNodes = (int)math.floor(2.*noOfNodes/3.); 
for (int o = 0; o < noOfHiddenNodes; o++){ 
    hiddenNodeLayer.add(new HiddenNode(input)); 
} 

UPDATE（順便說一句，是你的hiddenNodeLayer定義在哪裏？）：鑑於您已經定義了輸入作爲一個ArrayList，你可以在同一個推新節點有作爲hiddenNodeLayer。

private List<InputNode> input = new ArrayList<InputNode>(); // Input Nodes 

for (int n = 0; n < noOfNodes; n++){ 
    input.add(new InputNode(0.0)); 
} 
//Create 8 HiddenNode objects **HAVING PROBLEMS HERE** 
int noOfHiddenNodes = (int)math.floor(2.*noOfNodes/3.); 
for (int o = 0; o < noOfHiddenNodes; o++){ 
    hiddenNodeLayer.add(new HiddenNode(input)); 
}