Question

当我尝试运行该程序时，它将接受输入，但仅对所有打印输出0.0 0.0 0.0。我需要它来打印估算的数字，然后将平均值打印到2位小数精度。为什么只打印0，而不打印数字

import java.util.Scanner;
import java.util.Arrays;

public class pcCalculate 


{
     double[] pcPrice = new double [10];
    public static void main(String[] args)
    {
        Quiz input = new Quiz();
        Quiz display = new Quiz();
        Quiz avgCalc = new Quiz();
        input.arrayInput();
        display.displayPCPrices();
        avgCalc.avgPCCalc();
}

public void displayPCPrices()
{
    System.out.println(Arrays.toString(pcPrice));
}

   public double avgPCCalc() 
   {
    int sum = 0;
        for (int i=0; i < pcPrice.length; i++)
        {
                 sum = (int) (sum + pcPrice[i]);
        }
double average = sum / (double)pcPrice.length;
return average;
   }
          public void arrayInput()
     {

    Scanner price = new Scanner(System.in);
     System.out.println("Enter Prices");
        pcPrice[0] = price.nextDouble();
        pcPrice[1] = price.nextDouble();
        pcPrice[2] = price.nextDouble();
        pcPrice[3] = price.nextDouble();
        pcPrice[4] = price.nextDouble();
        pcPrice[5] = price.nextDouble();
        pcPrice[6] = price.nextDouble();
        pcPrice[7] = price.nextDouble();
        pcPrice[8] = price.nextDouble();
        pcPrice[9] = price.nextDouble();
  }

}

Answer 1

从主目录调用displayPCPrices方法，并将pcPrice作为参数传递：

import java.util.Scanner;
import java.util.Arrays;

public class pcCalculate
{
    public static void main(String[] args)
    {
        double[] pcPrice = new double [10];

        Scanner price = new Scanner(System.in);
        System.out.println("Enter Prices");
        pcPrice[0] = price.nextDouble();
        pcPrice[1] = price.nextDouble();
        pcPrice[2] = price.nextDouble();
        pcPrice[3] = price.nextDouble();
        pcPrice[4] = price.nextDouble();
        pcPrice[5] = price.nextDouble();
        pcPrice[6] = price.nextDouble();
        pcPrice[7] = price.nextDouble();
        pcPrice[8] = price.nextDouble();
        pcPrice[9] = price.nextDouble();

        displayPCPrices(pcPrice);

    }

    public void displayPCPrices(Array pcPrice)
    {
        System.out.println(Arrays.toString(pcPrice));
    }

   public double avgPCCalc() 
   {
       int sum = 0;
       for (int i=0; i < pcPrice.length; i++)
       {
           sum = (int) (sum + pcPrice[i]);
       }
       double average = sum / (double)pcPrice.length;
       return average;
   }
}

编辑：就像您知道的那样，main（String [] args）是您的程序将始终启动的地方，您从那里调用其他方法并开始工作。没有别的会调用您的main方法。

EDIT2：如果您想就您的编码实践进行对话，向我发送消息，我看到您已经更改了问题，并且缺少了一些可以帮助您轻松解决此问题的基本概念。

Answer 2

数组在循环中更好，在这种情况下，我会这样：

import java.util.Scanner;
import java.util.Arrays;

public class pcCalculate {

    double[] pcPrice = new double [10];
    public static void main(String[] args){

    Scanner price = new Scanner(System.in);
    for(int i=0; i< pcPrice.length; i++){
    System.out.print("Set Price " + (i + 1) + ":");
    pcPrice[i] = price.nextDouble();
    }
displayPCPrices();
System.out.println("The average is :" + avgPCCalc());
}

public void displayPCPrices()
{
    System.out.println("The prices are: " + "\n");
    for(int i = 0; i< pcPrice.length; i++){
    System.out.print(pcPrice[i] + " ");
    }

}

   public double avgPCCalc() 
   {
    double sum = 0;
        for (int i=0; i < pcPrice.length; i++)
            {
                 sum += pcPrice[i];
           }
    double average = sum / 10;
    return average;
   }


}

如何获得其他方法以正确读取数组

2 个答案: