Det virker?

app/src/main/java/com/example/ulrich/contextapp/datawindow/DataWindow.java

@@ -0,0 +1,16 @@
+package com.example.ulrich.contextapp.datawindow;
+
+/**
+ * Created by Anders on 23-11-2017.
+ */
+
+public class DataWindow {
+    private float min, max, stDevMag;
+
+    public DataWindow(float min, float max, float stDevMag)
+    {
+        this.min = min;
+        this.max = max;
+        this.stDevMag = stDevMag;
+    }
+}

app/src/main/java/com/example/ulrich/contextapp/widgets/AccelerometerWidget.java

@@ -3,90 +3,108 @@
 /**
  * Created by anders on 11/21/17.
  */
-import android.content.Context;
+
 import android.hardware.Sensor;
 import android.hardware.SensorEvent;
 import android.hardware.SensorEventListener;
 import android.hardware.SensorManager;
-import android.os.Environment;
-import android.support.v7.app.AppCompatActivity;
-import android.os.Bundle;
-import android.widget.TextView;
-
-
-import java.util.*;
-import java.util.Collections;
-
-
-import weka.filters.*;
-import weka.classifiers.*;
-import weka.core.*;
-
+import android.util.Log;
+import com.example.ulrich.contextapp.datawindow.DataWindow;
+import java.util.ArrayList;
+import java.lang.Math;
 
 public class AccelerometerWidget implements SensorEventListener{
 
     private SensorManager senSensorManager;
     private Sensor senAccelerometer;
     private long lastUpdate = 0;
-    private float last_x, last_y, last_z;
-    private static final int SHAKE_THRESHOLD = 600;
-    private ArrayList <Double> dataList = new ArrayList<Double>();
+    private ArrayList<DataWindow> dataWindows= new ArrayList<>();
+    private float[] xReadings = new float[128];
+    private float[] yReadings = new float[128];
+    private float[] zReadings = new float[128];
+    private int currentIndex = 0;
+    private final int SAMPLE_FREQUENCY = 40;
 
     public AccelerometerWidget(SensorManager manager){
         senSensorManager = manager;
         senAccelerometer = senSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
         senSensorManager.registerListener(this, senAccelerometer , SensorManager.SENSOR_DELAY_NORMAL);
     }
 
-    @Override
-    public void onAccuracyChanged(Sensor sensor, int i) {
-    }
     @Override
     public void onSensorChanged(SensorEvent sensorEvent) {
         Sensor mySensor = sensorEvent.sensor;
 
         if (mySensor.getType() == Sensor.TYPE_ACCELEROMETER) {
-            float x = sensorEvent.values[0];
-            float y = sensorEvent.values[1];
-            float z = sensorEvent.values[2];
-
-            float r = x*x + y*y + z*z;
-            double k = Math.sqrt(r);
-
             long curTime = System.currentTimeMillis();
 
-            if ((curTime - lastUpdate) > 200) {
-                long diffTime = (curTime - lastUpdate);
+            // Only add data point for each SAMPLE_FREQUENCY ms
+            if ((curTime - lastUpdate) > SAMPLE_FREQUENCY){
                 lastUpdate = curTime;
-                float speed = Math.abs(x + y + z - last_x - last_y - last_z)/ diffTime * 10000;
-                //TextView hej =(TextView)findViewById(R.id.hej);
-                //hej.setText(k + "");
-                dataList.add(k);
-                if (speed > SHAKE_THRESHOLD) {
 
+                float x = sensorEvent.values[0];
+                float y = sensorEvent.values[1];
+                float z = sensorEvent.values[2];
+
+                if(currentIndex > 127)
+                    currentIndex = 0;
+
+                xReadings[currentIndex] = x;
+                yReadings[currentIndex] = y;
+                zReadings[currentIndex] = z;
+
+                // When adding a datapoint to the middle or the end of the x,y,z reading arrays -
+                // Make a new DataWindow object (the last check is to avoid making a DataWindow for-
+                // the first 64 readings.)
+                Log.d("hey","currentIndex: "+ currentIndex + " : " + (xReadings[127] != 0L));
+                if((currentIndex == 63 || currentIndex == 127) && xReadings[127] != 0L)
+                {
+                    makeDataWindow();
                 }
 
-                last_x = x;
-                last_y = y;
-                last_z = z;
+                currentIndex++;
             }
         }
     }
 
-    public void getMax(){
-        double i = Collections.max(dataList);
-        //TextView max =(TextView)findViewById(R.id.max);
-        //max.setText(i + "");
-    }
 
-    public void getMin(){
-        double i = Collections.min(dataList);
-        //TextView min =(TextView)findViewById(R.id.min);
-        //min.setText(i + "");
-    }
+    private void makeDataWindow()
+    {
 
-    public void getStdDevOfMagnitude(){}
+        // Calculate min, max
+        int N = 128; //window size
+        float min = Float.MAX_VALUE;
+        float max = Float.MIN_VALUE;
+        float sum = 0;
+        for (int i = 0; i < N; i++) {
+            float val = sample(xReadings[i],yReadings[i],zReadings[i]);
+            if(val < min) { min = val; }
+            if(val > max) { max = val; }
+            sum += val;
+        }
 
+        // Calculate stdDev
+        float mean = sum/N;
+        float summedDifference = 0;
+        for (int i = 0; i < N; i++) {
+            summedDifference += Math.pow(sample(xReadings[i],yReadings[i],zReadings[i]) - mean,2);
+        }
+        float stdDev = (float)Math.sqrt(summedDifference / (N-1)); //standard deviation
 
+        Log.d("newWindow", "Making new datawindow: " + min + ":" + max + ":" +stdDev );
+        // Add new DataWindow
+        DataWindow newWindow = new DataWindow(min, max,stdDev);
+        dataWindows.add(newWindow);
+    }
+
+    private float sample(float x, float y, float z){
+        double x_squared = Math.pow(x,2);
+        double y_squared = Math.pow(y,2);
+        double z_squared = Math.pow(z,2);
+        return (float)Math.sqrt(x_squared + y_squared + z_squared);
+    }
+
+    @Override
+    public void onAccuracyChanged(Sensor sensor, int i) {}
 
 }