移动加速度传感器的平均方法

Question

我正在试图做简单移动平均为总加速度。简单地说，移动平均值应该采用TotalAccelerate矢量的4个样本，并在运行时对其进行平均。然后移动一个样本并平均下四个样本，以此类推。 我写的代码不起作用。它因我不知道的原因而坠毁。我应该使用单独的线程来做计算吗？如果你写一个伪代码，我将不胜感激。

double TotalAccelerate; 
ArrayList<Double> listPeaks; 
//for Accelermeter 
sm = (SensorManager) getSystemService(Context.SENSOR_SERVICE); 
sensorText = (TextView) findViewById(R.id.sensor); 
accelermeter = sm.getDefaultSensor(Sensor.TYPE_ACCELEROMETER); 
sm.registerListener(this, accelermeter, SensorManager.SENSOR_DELAY_NORMAL); 
mDetector = new GestureDetectorCompat(this, new MyGestureListener()); 

    @Override 
public final void onSensorChanged(SensorEvent event) { 
    // The light sensor returns a single value. 
    // Many sensors return 3 values, one for each axis. 

     //If my ToggleButton Ischecked and isListening=true.(at Oncreate method) 
    if (isListening) { 
     double xx = event.values[0]; 
     double yy = event.values[1]; 
     double zz = event.values[2]; 
     //The result will be one vector of array 
     TotalAccelerate = Math.round(Math.sqrt(Math.pow(xx, 2) 
       + Math.pow(yy, 2) 
       + Math.pow(zz, 2))); 
     Log.i(DEBUG, "Accelerometer = " + TotalAccelerate); 

     listPeaks.add(TotalAccelerate); 
     //findPeaks(listPeaks); 

     Log.i(DEBUG, "list values " + listPeaks); 
     //Find moving average - window size= 4 
     MovingAverage ma = new MovingAverage(4); 
     ma.newNum(TotalAccelerate); 
     float valueAfterMovingAverage = (float) ma.getAvg(); 
     sensorText.setText((int) valueAfterMovingAverage); 
    } 

} 

public Queue<Double> window = new LinkedList<Double>(); 
public int p; 
public double sum; 

///Moving Average class. 
public class MovingAverage { 
    public MovingAverage(int period) { 
     assert period > 0 : "Period must be a positive integer"; 
     p = period; 
    } 

    public void newNum(double num) { 
     sum += num; 
     window.add(num); 
     if (window.size() > p) { 
      sum -= window.remove(); 
     } 
    } 

    public double getAvg() { 
     if (window.isEmpty()) return 0; // technically the average is undefined 
     return sum/window.size(); 
    } 

} 

这是我得到的错误：

at android.content.res.Resources.getText(Resources.java:275) 
                      at android.widget.TextView.setText(TextView.java:4264) 
                      at com.example.arduinosensors.MainActivity.onSensorChanged(MainActivity.java:230) 
                      at android.hardware.SystemSensorManager$SensorEventQueue.dispatchSensorEvent(SystemSensorManager.java:436) 
                      at android.os.MessageQueue.nativePollOnce(Native Method) 
                      at android.os.MessageQueue.next(MessageQueue.java:143) 
                      at android.os.Looper.loop(Looper.java:122) 
                      at android.app.ActivityThread.main(ActivityThread.java:5354) 
                      at java.lang.reflect.Method.invoke(Native Method) 
                      at java.lang.reflect.Method.invoke(Method.java:372) 
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908) 
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703) 

Answer 1

改变这一行：

sensorText.setText((int) valueAfterMovingAverage); 

到：

sensorText.setText(String.valueOf((int) valueAfterMovingAverage));