java - 平均医学模式方法的两个问题

Question

这是我完成的代码，用于计算平均值、中位数、众数、标准差、最小值、最大值、q1、q2 和 5 个数字摘要，这些摘要应该作为数组返回。据我所知，该数组的格式正确，但由于某种奇怪的原因，返回数组吐出这个 5 数字摘要:[D@689af4 我不知道为什么或如何要解决这个问题。当我需要输出-1时，该模式也输出22。有没有人可以看看这个并告诉我出了什么问题以及我可以做些什么来解决这些问题？

import java.util.Arrays;

class Statistics {
  public static void main(String[] args)
  {
     int[] a = new int[]{22,44,66,55,33};

           bubbleSort(a);
           double mean; 
           double median; 
           int mode;
           int max;
           int min;
           double sd;
           int q1; 
           int q3; 
           double[] vals; 


           mode = calcMoe (a);
           median = calcMed (a);
           mean = calcMean (a);
           max =calcMax (a);
           min =calcMin (a);
           sd =calcSd (a);
           q1=calcQuart1 (a); 
           q3=calcQuart3 (a); 
           vals=calcNumsum (a);



           System.out.println("Median:"+median); 
           System.out.println("Mean:"+mean); 
           System.out.println("Mode:"+mode);
           System.out.println("max number is : " + max);
           System.out.println("min number is : " + min);
           System.out.println("Standard Deviation:"+sd);
           System.out.println("1st Quartile:"+q1); 
           System.out.println("3rd Quartile:"+q3);
           System.out.println("5 number Summary:"+vals);

  }



  public static double calcMean(int[] a)
  {

  // int[]array = {22,44,66,55,33}; 
    int i;//=0;
    int sum=0;
    double mean =0;
    for ( i=0;i<a.length;i++)
    { 
      //System.out.println(a[i]);
      sum=sum+a[i];
    }
    {  mean = ((double) sum/ ((double) a.length));
      //System.out.println(); } {

        return mean;}
      } 
   //Calulate median

   public static double calcMed(int[] a)
 {// Sort array 
  int[] sorta = bubbleSort(a);

  double median = 0;
  if (a.length % 2 == 0)

   {
    int indexA = (sorta.length - 1) / 2;
   int indexB = sorta.length / 2;

   median = ((double) (sorta[indexA] + sorta[indexB])) / 2;
  }
 // Else if our array's length is odd
  else  
  {
   int index = (sorta.length - 1) / 2;
   median = a[ index ];
  }

  // Print the values of the sorted array
  for (int v : sorta) 
  {
    System.out.println(v);
  }

  return median; 

   }

   public static int[] bubbleSort(int[] a)
    {
     //outer loop 
    for(int luck=0; luck<a.length -1; luck++){
     for (int juck=1; juck<a.length - luck; juck++){
       if (a[juck-1]>a[juck]){
         int temp= a[juck];
         a[juck]=a[juck-1];
         a[juck-1]=temp;
          //System.out.printf("unsorted array after %d pass %s: %n", luck+1,     Arrays.toString(a));
       }
      }
     }
    return a;
    }





 public static int calcMoe(int[] a)
{
    Arrays.sort(a);

     int count2 = 0;
     int count1 = 1;
     int pupular1 =0;
     int mode =0;


    for (int i = 0; i < a.length; i++)
    {
            pupular1 = a[i];
            count1 = 1;    

        for (int j = i + 1; j < a.length; j++)
        {
            if (pupular1 == a[j]) count1++;
        }

        if (count1 > count2)
        {
                mode = pupular1;
                count2 = count1;
        }

        if (count1 == count2)
        {
            mode = Math.min(mode, pupular1);

         }

         }


     return mode;
  }



public static int calcMax(int[] a) {
 //int min = a[0];
 int max = a[0];
  for (int i = 1; i <= a.length - 1; i++) {
  if (max < a[i]) {
   max = a[i];
   }
  }
   return max; 
}
public static int calcMin(int[] a) {
 int min = a[0];

  for (int i = 1; i <= a.length - 1; i++) {
  if (min > a[i]) {
   min = a[i];
  }
  }
   return min; 
}
public static double calcSd(int[] a) {
  //int sum = 0;
  //int max = 0;
  //int min = a[0];
  double sd = 0;
  int i = 0;
  double mean =0;
  sd=0;
    for ( i=0;i<a.length;i++)
        {
       sd += ((a[i] - mean)*(a[i] - mean)) / (a.length - 1);
    }  


 double standarddeviation = Math.sqrt(sd);
 {
 }
 return standarddeviation; 
 }
public static int calcQuart1(int[] a) {
  int[] sorta = bubbleSort(a);

  int q1 = 0;
  {
   int index = (sorta.length - 1) / 4;
   q1 = a[ index ] ;
  }


  for (int v : sorta) 
  {
    System.out.println(v);
  }

  return q1; 
 }
public static int calcQuart3(int[] a) {
  int[] sorta = bubbleSort(a);

  int q3 = 0;
  {
   int index = 3*(sorta.length - 1) / 4;
   q3 = a[ index ] ;
  }


  for (int v : sorta) 
   {
    System.out.println(v);
  }

  return q3; 
}
   public static double[] calcNumsum(int[] a) { 


  double median = calcMed (a);
  double max =calcMax (a);
  double min =calcMin (a);
  double q1=calcQuart1 (a); 
  double q3=calcQuart3 (a); 
  double[] vals = new double[5];
  vals[0] = min; 
  vals [1] = q1; 
  vals [2] = median; 
  vals [3] = q3; 
  vals [4] = max; 
  return vals;
}
   }

Answer 1

这一行:

System.out.println("5 number Summary:"+vals);

只需获取vals，将其转换为String，然后打印它。 Java 中数组类型的默认 toString 实现会生成您注意到的输出:整体类型([ for 'array')、存储在数组中的类型 ( D 代表 double)、一个 @ 符号以及数组在内存中的位置(在本例中为 689af4)。

为了获得对您的目的更有用的输出，您可以使用 Arrays.toString :

System.out.println("5 number summary: " + Arrays.toString(vals));