java - 如何在 Java 中创建移动平均线

Question

我需要一个程序来计算一组数字的移动平均值(我使用了 4，9、3.14、1.59、86.0、35.2、9.98、1.00、0.01、2.2 和 3.76)。当我运行这个时，它打印出来“17.859999999999996”九次。你们看到任何错误吗？

import java.util.*;

public class MovingAverage
{
    public static void main(String args[])
    {
        Scanner scan = new Scanner(System.in);
        // Read in the length of the moving average and the number
        // of data points
        int averageLength = scan.nextInt();
        int numDataPoints = scan.nextInt();
        // Create an array to hold the data points, and another to
        // hold the moving average
        double data[] = new double[numDataPoints];
        double movingAverage[] = new double[numDataPoints];
        // Read in all of the data points using a for loop
        for(int i = 0; i< numDataPoints; i++)
        {
            data[i]=scan.nextDouble();
        }
        // Create the moving average
        for (int i=0; i<numDataPoints; i++) 
        {
            // Calculate the moving average for index i and put
            // it in movingAverage[i]. (Hint: you need a for
            // loop to do this. Make sure not to use i as your
            // loop variable. Also, make sure to handle the
            // case where i is not large enough (when i<averageLength-1). 
            double sum= 0.0;
            for(int j=0; j<numDataPoints; j++)
            {

                sum=sum+data[j];
                movingAverage[i]=sum/j;
            }

        }
        // Print the moving average, one value per line
        for (int i=0; i<numDataPoints; i++)
        {
            System.out.println(movingAverage[i]);
        }
    }
}

Answer 1

由于这看起来像是一项作业，我会给你一个提示。

移动平均线有一个窗口。在这种情况下，窗口的宽度是averageLength。这是您平均获得的分数。

您需要在创建移动平均线的循环中以某种方式使用averageLength。现在你不需要了。