Question

此代码应该采用csv数据并获取数据的移动平均值。附件是在java中获得的图的图表。该图与原始图相同。目标是摆脱压力20以上的所有数据，并使其看起来像方波更平滑。但是在我做了移动平均线之后，它仍然给了我相同的图形。另外，我怎样才能在（0-50）秒之间消除这个尖峰。移动平均线不起作用。我的移动平均线有问题，但我无法弄清楚。请帮忙。感谢

import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Random;


public class MovinAverage {
    private static double freqS = 100.000;
    private static double sigma = 0.05;
    private static ArrayList<Double> noise = null;

    static ArrayList<Double> sec = null;
    private static double[] Pressure = new double[20481];
    private static ArrayList<Double> noisySignal = null;

    public static void recordVoice() throws NumberFormatException, IOException{
        BufferedReader read = new BufferedReader(new FileReader(new File("C:\\Users\\KwakuK\\Downloads\\smith2.csv")));     
        String currentLine = new String();
        currentLine = read.readLine();       
        double i = 0;
        //make some computation
        while((currentLine = read.readLine()) != null)
        {
            String[] numbers = currentLine.split(","); // split the string into sub strings
            if(numbers.length >= 3)
            {
                    System.out.println("currentLine: " + " " + currentLine);

            Pressure[(int) i++] = Double.parseDouble(numbers[2]); // when you do the 2, it's the third column which is the pressure

        }
    }

    }
    public static void setupFirstPlot() throws FileNotFoundException{

        sec = new ArrayList<Double>();
        double ws = 1/freqS;
        double n = (Pressure.length)*ws;

        for(double i = 0.01; i < n; i = i + ws){ 
            sec.add(i);
        }
        PrintWriter pw = new PrintWriter(new File("plot3.csv"));
        for(int i = 0; i < Pressure.length; i++){
            pw.write(sec.get(i)+","+Pressure[i]+"\n");
        }
        pw.close();
    }

    public static double movingaverage(){
        double sum = 0;
        for (int i = 0; i < Pressure.length; i++){
            sum +=Pressure[i];
        }
        double average = sum / Pressure.length;

    return average;

    }


    public static void setupNoisySignal(){
        noise = new ArrayList<Double>(Pressure.length);
        noisySignal = new ArrayList<Double>(Pressure.length);

        Random rand = new Random();
        for(int i = 0; i < Pressure.length; i++){
            double value = rand.nextGaussian()*sigma;
            noise.add(value);
            noisySignal.add(value + Pressure[i]);
        }

    }

    public static void playSignal(ArrayList<Double> data) throws IOException{

            ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
            DataOutputStream dataStream = new DataOutputStream(byteStream);
            for(int i = 0; i < data.size(); i++){
                dataStream.writeDouble(data.get(i));
            }
            dataStream.close();
            byteStream.close();

    }
    public static void main(String[] args) throws NumberFormatException, IOException {
        //Populate recording data and plotting data
        recordVoice();
        setupFirstPlot();
        setupNoisySignal();
        playSignal(noisySignal);
        System.out.println();
        System.out.println(movingaverage());

    }

}

Answer 1

在给定窗口上完成移动平均线。因此，您需要将该窗口传递给您的平均方法（并使用它）。所以简而言之，你不会包含所有数据，你会忘记＆＃34;所有通过该窗口的数据。因此，它是信号中windowLength最后数据的平均值。

简单移动平均线（SMA）是前n个数据的未加权平均值。

来自https://en.wikipedia.org/wiki/Moving_average

public static double movingaverage(int windowLength) {
    double sum = 0;
    for (int i = Math.max(0, Pressure.length-windowLength); i < Pressure.length; i++){
        sum += Pressure[i];
    }
    double average = sum / windowLength;

    return average;
}

在java中绘制并获取CSV数据的移动平均值

1 个答案: