java - 使用数组作为方法 (Java)

Question

我在编译我的类时遇到问题。它给我错误，例如“无法取消引用 double ”和“找不到符号”。

潜水员是:

 public class MinilabArraysDriver{
    public static void main(String[ ] args){
       //create a 1d array of ints
       int[ ] array1d = { 8, 8, 7, 5, 3 };

       //call mean1d Method to find the mean (note the static call...)
       double theMean = MinilabArrays.mean1d(array1d);

       //print the original array and the mean
       System.out.print("The mean of: { ");
        for (int i=0; i<array1d.length; i++){
              if (i != 0)
                  System.out.print("   ");
             //print first for separation (except before first element)
             System.out.print(array1d[i]);
         }
        System.out.print(" }   is:  " + theMean);
        //------------------------------------------------------------
        System.out.println("\n\n");
        //create a 2d array of doubles
        double[ ][ ] array2d =  {{ 3.4,  5.1,  8.0},
                                 { 5.23,  8.2 },
                                 { 10.7 },
                                 { 2.9 }
                                };
        //call sum2d to get the sum
        double total = MinilabArrays.sum2d(array2d);

        //print the 2D array
        for (int row=0; row<array2d.length; row++){
             System.out.println();
             for (int col=0; col<array2d[row].length; col++)
                  System.out.print(array2d[row][col] + "\t");
            }
        //print the result
        System.out.println("\n\nTotal of 2d array is: " + total);
        System.out.println("\n\n");
       }
}

这是我正在尝试编写的类:

public class MinilabArrays{
  public static double mean1d(int[ ] theMean){
    double total = 0;
    for (int i = 0 ;i < theMean.length ; i++){
            total = total + theMean [ i ];
            total = total / theMean.length;
            return total;
        }
    }

   public static double sum2d(double [ ] theSum){
    double total2, total3, total4 = 0;
    for(int row=0 ; row < theSum.length ; row++){
        for (int col=0 ; col<theSum[row].length ; col++)
            total2 = total2 + theSum[col];
        }
    total3 = total3 + theSum[row];
    total4 = total3 + total2;
    return total4;
   }
}

对于“mean1d”，我试图找到给定数字的平均值，而对于“sum2d”，我试图找到给定数字的总和。

抱歉，如果我的代码很愚蠢或愚蠢。如果它不允许我编译，我就无法检查它。

谢谢你帮助我!

Answer 1

您通过在参数中传递 2D 数组来调用 sum2d 方法，并将该方法声明为 1D 数组作为参数。

MinilabArrays.java

public static double sum2d(double[][] theSum) {
    double total2 = 0;
    for (int row = 0; row < theSum.length; row++) {
        for (int col = 0; col < theSum[row].length; col++){
            total2 = total2 + theSum[row][col];
        }
    }
    return total2;
}