hello all,
i try to implement sensor fusion code from android code under processing. I'm pretty beginner to java and processing, so it's pretty hard for me to make it works. the code is from here: http://www.thousand-thoughts.com/2012/03/android-sensor-fusion-tutorial/
sensor fusion is a triple integral from gyro, accell and magnet. It eliminates the drift from gyros, and stabilize the orientation of the tablet.
the code gives the fusedOrientation[3] calculated...but when I try to catch thoses values, processing tells me:

"can not find symbol."
I comment the original gui lines from the android code- the void draw() is at the end of the sketch.
Any help would be really appreciated- this must be a java problem…thanks in advance.

1.     
   
   //adaptation fusedOrientation
   
   import android.app.Activity;
   import android.hardware.Sensor;
   import android.hardware.SensorEvent;
   import android.hardware.SensorEventListener;
   import android.hardware.SensorManager;
   import android.os.Bundle;
   //import android.os.Handler;
   import android.widget.RadioGroup;
   //import android.widget.TextView;
   
   import java.math.RoundingMode;
   import java.text.DecimalFormat;
   import java.util.Timer;
   import java.util.TimerTask;
   
   //SensorManager sensorManager; // keep track of sensor
   
   public class SensorFusionActivity extends Activity
   implements SensorEventListener, RadioGroup.OnCheckedChangeListener {
   
     private SensorManager mSensorManager = null;
   
     // angular speeds from gyro
     private float[] gyro = new float[3];
   
     // rotation matrix from gyro data
     private float[] gyroMatrix = new float[9];
   
     // orientation angles from gyro matrix
     private float[] gyroOrientation = new float[3];
   
     // magnetic field vector
     private float[] magnet = new float[3];
   
     // accelerometer vector
     private float[] accel = new float[3];
   
     // orientation angles from accel and magnet
     private float[] accMagOrientation = new float[3];
   
     // final orientation angles from sensor fusion
     private float[] fusedOrientation = new float[3];
   
     // accelerometer and magnetometer based rotation matrix
     private float[] rotationMatrix = new float[9];
   
     public static final float EPSILON = 0.000000001f;
     private static final float NS2S = 1.0f / 1000000000.0f;
     private float timestamp;
     private boolean initState = true;
   
     public static final int TIME_CONSTANT = 30;
     public static final float FILTER_COEFFICIENT = 0.98f;
     private Timer fuseTimer = new Timer();
   
     // The following members are only for displaying the sensor output.//
   //  public Handler mHandler;
   //  private RadioGroup mRadioGroup;
   //  private TextView mAzimuthView;
   //  private TextView mPitchView;
   //  private TextView mRollView;
   //  private int radioSelection;
     DecimalFormat d = new DecimalFormat("#.##");
   
   
     @Override
       public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);
   
       gyroOrientation[0] = 0.0f;
       gyroOrientation[1] = 0.0f;
       gyroOrientation[2] = 0.0f;
   
       // initialise gyroMatrix with identity matrix
       gyroMatrix[0] = 1.0f;
       gyroMatrix[1] = 0.0f;
       gyroMatrix[2] = 0.0f;
       gyroMatrix[3] = 0.0f;
       gyroMatrix[4] = 1.0f;
       gyroMatrix[5] = 0.0f;
       gyroMatrix[6] = 0.0f;
       gyroMatrix[7] = 0.0f;
       gyroMatrix[8] = 1.0f;
   
       // get sensorManager and initialise sensor listeners
       mSensorManager = (SensorManager) this.getSystemService(SENSOR_SERVICE);
       initListeners();
   
       // wait for one second until gyroscope and magnetometer/accelerometer
       // data is initialised then scedule the complementary filter task
       fuseTimer.scheduleAtFixedRate(new calculateFusedOrientationTask(),
       1000, TIME_CONSTANT);
   
       // GUI stuff
   //    mHandler = new Handler();
   //    radioSelection = 0;
   //    d.setRoundingMode(RoundingMode.HALF_UP);
   //    d.setMaximumFractionDigits(3);
   //    d.setMinimumFractionDigits(3);
   
   
   
   
   //    mRadioGroup.setOnCheckedChangeListener(this);
     }
   
     @Override
       public void onStop() {
       super.onStop();
       // unregister sensor listeners to prevent the activity from draining the device's battery.
       mSensorManager.unregisterListener(this);
     }
   
     @Override
       protected void onPause() {
       super.onPause();
       // unregister sensor listeners to prevent the activity from draining the device's battery.
       mSensorManager.unregisterListener(this);
     }
   
     @Override
       public void onResume() {
       super.onResume();
       // restore the sensor listeners when user resumes the application.
       initListeners();
     }
   
     // This function registers sensor listeners for the accelerometer, magnetometer and gyroscope.
     public void initListeners() {
       mSensorManager.registerListener(this,
       mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
       SensorManager.SENSOR_DELAY_FASTEST);
   
       mSensorManager.registerListener(this,
       mSensorManager.getDefaultSensor(Sensor.TYPE_GYROSCOPE),
       SensorManager.SENSOR_DELAY_FASTEST);
   
       mSensorManager.registerListener(this,
       mSensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD),
       SensorManager.SENSOR_DELAY_FASTEST);
     }
   
     @Override
       public void onAccuracyChanged(Sensor sensor, int accuracy) {
     }
   
     @Override
       public void onSensorChanged(SensorEvent event) {
       switch(event.sensor.getType()) {
       case Sensor.TYPE_ACCELEROMETER:
         // copy new accelerometer data into accel array and calculate orientation
         System.arraycopy(event.values, 0, accel, 0, 3);
         calculateAccMagOrientation();
         break;
   
       case Sensor.TYPE_GYROSCOPE:
         // process gyro data
         gyroFunction(event);
         break;
   
       case Sensor.TYPE_MAGNETIC_FIELD:
         // copy new magnetometer data into magnet array
         System.arraycopy(event.values, 0, magnet, 0, 3);
         break;
       }
     }
   
     // calculates orientation angles from accelerometer and magnetometer output
     public void calculateAccMagOrientation() {
       if (SensorManager.getRotationMatrix(rotationMatrix, null, accel, magnet)) {
         SensorManager.getOrientation(rotationMatrix, accMagOrientation);
       }
     }
   
     // This function is borrowed from the Android reference
     // at http://developer.android.com/reference/android/hardware/SensorEvent.html#values
     // It calculates a rotation vector from the gyroscope angular speed values.
     private void getRotationVectorFromGyro(float[] gyroValues,
     float[] deltaRotationVector,
     float timeFactor)
     {
       float[] normValues = new float[3];
   
       // Calculate the angular speed of the sample
       float omegaMagnitude =
         (float)Math.sqrt(gyroValues[0] * gyroValues[0] +
         gyroValues[1] * gyroValues[1] +
         gyroValues[2] * gyroValues[2]);
   
       // Normalize the rotation vector if it's big enough to get the axis
       if (omegaMagnitude > EPSILON) {
         normValues[0] = gyroValues[0] / omegaMagnitude;
         normValues[1] = gyroValues[1] / omegaMagnitude;
         normValues[2] = gyroValues[2] / omegaMagnitude;
       }
   
       // Integrate around this axis with the angular speed by the timestep
       // in order to get a delta rotation from this sample over the timestep
       // We will convert this axis-angle representation of the delta rotation
       // into a quaternion before turning it into the rotation matrix.
       float thetaOverTwo = omegaMagnitude * timeFactor;
       float sinThetaOverTwo = (float)Math.sin(thetaOverTwo);
       float cosThetaOverTwo = (float)Math.cos(thetaOverTwo);
       deltaRotationVector[0] = sinThetaOverTwo * normValues[0];
       deltaRotationVector[1] = sinThetaOverTwo * normValues[1];
       deltaRotationVector[2] = sinThetaOverTwo * normValues[2];
       deltaRotationVector[3] = cosThetaOverTwo;
     }
   
     // This function performs the integration of the gyroscope data.
     // It writes the gyroscope based orientation into gyroOrientation.
     public void gyroFunction(SensorEvent event) {
       // don't start until first accelerometer/magnetometer orientation has been acquired
       if (accMagOrientation == null)
         return;
   
       // initialisation of the gyroscope based rotation matrix
       if (initState) {
         float[] initMatrix = new float[9];
         initMatrix = getRotationMatrixFromOrientation(accMagOrientation);
         float[] test = new float[3];
         SensorManager.getOrientation(initMatrix, test);
         gyroMatrix = matrixMultiplication(gyroMatrix, initMatrix);
         initState = false;
       }
   
       // copy the new gyro values into the gyro array
       // convert the raw gyro data into a rotation vector
       float[] deltaVector = new float[4];
       if (timestamp != 0) {
         final float dT = (event.timestamp - timestamp) * NS2S;
         System.arraycopy(event.values, 0, gyro, 0, 3);
         getRotationVectorFromGyro(gyro, deltaVector, dT / 2.0f);
       }
   
       // measurement done, save current time for next interval
       timestamp = event.timestamp;
   
       // convert rotation vector into rotation matrix
       float[] deltaMatrix = new float[9];
       SensorManager.getRotationMatrixFromVector(deltaMatrix, deltaVector);
   
       // apply the new rotation interval on the gyroscope based rotation matrix
       gyroMatrix = matrixMultiplication(gyroMatrix, deltaMatrix);
   
       // get the gyroscope based orientation from the rotation matrix
       SensorManager.getOrientation(gyroMatrix, gyroOrientation);
     }
   
     private float[] getRotationMatrixFromOrientation(float[] o) {
       float[] xM = new float[9];
       float[] yM = new float[9];
       float[] zM = new float[9];
   
       float sinX = (float)Math.sin(o[1]);
       float cosX = (float)Math.cos(o[1]);
       float sinY = (float)Math.sin(o[2]);
       float cosY = (float)Math.cos(o[2]);
       float sinZ = (float)Math.sin(o[0]);
       float cosZ = (float)Math.cos(o[0]);
   
       // rotation about x-axis (pitch)
       xM[0] = 1.0f;
       xM[1] = 0.0f;
       xM[2] = 0.0f;
       xM[3] = 0.0f;
       xM[4] = cosX;
       xM[5] = sinX;
       xM[6] = 0.0f;
       xM[7] = -sinX;
       xM[8] = cosX;
   
       // rotation about y-axis (roll)
       yM[0] = cosY;
       yM[1] = 0.0f;
       yM[2] = sinY;
       yM[3] = 0.0f;
       yM[4] = 1.0f;
       yM[5] = 0.0f;
       yM[6] = -sinY;
       yM[7] = 0.0f;
       yM[8] = cosY;
   
       // rotation about z-axis (azimuth)
       zM[0] = cosZ;
       zM[1] = sinZ;
       zM[2] = 0.0f;
       zM[3] = -sinZ;
       zM[4] = cosZ;
       zM[5] = 0.0f;
       zM[6] = 0.0f;
       zM[7] = 0.0f;
       zM[8] = 1.0f;
   
       // rotation order is y, x, z (roll, pitch, azimuth)
       float[] resultMatrix = matrixMultiplication(xM, yM);
       resultMatrix = matrixMultiplication(zM, resultMatrix);
       return resultMatrix;
     }
   
     private float[] matrixMultiplication(float[] A, float[] B) {
       float[] result = new float[9];
   
       result[0] = A[0] * B[0] + A[1] * B[3] + A[2] * B[6];
       result[1] = A[0] * B[1] + A[1] * B[4] + A[2] * B[7];
       result[2] = A[0] * B[2] + A[1] * B[5] + A[2] * B[8];
   
       result[3] = A[3] * B[0] + A[4] * B[3] + A[5] * B[6];
       result[4] = A[3] * B[1] + A[4] * B[4] + A[5] * B[7];
       result[5] = A[3] * B[2] + A[4] * B[5] + A[5] * B[8];
   
       result[6] = A[6] * B[0] + A[7] * B[3] + A[8] * B[6];
       result[7] = A[6] * B[1] + A[7] * B[4] + A[8] * B[7];
       result[8] = A[6] * B[2] + A[7] * B[5] + A[8] * B[8];
   
       return result;
     }
   
     class calculateFusedOrientationTask extends TimerTask {
       public void run() {
         float oneMinusCoeff = 1.0f - FILTER_COEFFICIENT;
   
         /*
                * Fix for 179∞ <--> -179∞ transition problem:
          * Check whether one of the two orientation angles (gyro or accMag) is negative while the other one is positive.
          * If so, add 360∞ (2 * math.PI) to the negative value, perform the sensor fusion, and remove the 360∞ from the result
          * if it is greater than 180∞. This stabilizes the output in positive-to-negative-transition cases.
          */
   
         // azimuth
         if (gyroOrientation[0] < -0.5 * Math.PI && accMagOrientation[0] > 0.0) {
           fusedOrientation[0] = (float) (FILTER_COEFFICIENT * (gyroOrientation[0] + 2.0 * Math.PI) + oneMinusCoeff * accMagOrientation[0]);
           fusedOrientation[0] -= (fusedOrientation[0] > Math.PI) ? 2.0 * Math.PI : 0;
         }
         else if (accMagOrientation[0] < -0.5 * Math.PI && gyroOrientation[0] > 0.0) {
           fusedOrientation[0] = (float) (FILTER_COEFFICIENT * gyroOrientation[0] + oneMinusCoeff * (accMagOrientation[0] + 2.0 * Math.PI));
           fusedOrientation[0] -= (fusedOrientation[0] > Math.PI)? 2.0 * Math.PI : 0;
         }
         else {
           fusedOrientation[0] = FILTER_COEFFICIENT * gyroOrientation[0] + oneMinusCoeff * accMagOrientation[0];
         }
   
         // pitch
         if (gyroOrientation[1] < -0.5 * Math.PI && accMagOrientation[1] > 0.0) {
           fusedOrientation[1] = (float) (FILTER_COEFFICIENT * (gyroOrientation[1] + 2.0 * Math.PI) + oneMinusCoeff * accMagOrientation[1]);
           fusedOrientation[1] -= (fusedOrientation[1] > Math.PI) ? 2.0 * Math.PI : 0;
         }
         else if (accMagOrientation[1] < -0.5 * Math.PI && gyroOrientation[1] > 0.0) {
           fusedOrientation[1] = (float) (FILTER_COEFFICIENT * gyroOrientation[1] + oneMinusCoeff * (accMagOrientation[1] + 2.0 * Math.PI));
           fusedOrientation[1] -= (fusedOrientation[1] > Math.PI)? 2.0 * Math.PI : 0;
         }
         else {
           fusedOrientation[1] = FILTER_COEFFICIENT * gyroOrientation[1] + oneMinusCoeff * accMagOrientation[1];
         }
   
         // roll
         if (gyroOrientation[2] < -0.5 * Math.PI && accMagOrientation[2] > 0.0) {
           fusedOrientation[2] = (float) (FILTER_COEFFICIENT * (gyroOrientation[2] + 2.0 * Math.PI) + oneMinusCoeff * accMagOrientation[2]);
           fusedOrientation[2] -= (fusedOrientation[2] > Math.PI) ? 2.0 * Math.PI : 0;
         }
         else if (accMagOrientation[2] < -0.5 * Math.PI && gyroOrientation[2] > 0.0) {
           fusedOrientation[2] = (float) (FILTER_COEFFICIENT * gyroOrientation[2] + oneMinusCoeff * (accMagOrientation[2] + 2.0 * Math.PI));
           fusedOrientation[2] -= (fusedOrientation[2] > Math.PI)? 2.0 * Math.PI : 0;
         }
         else {
           fusedOrientation[2] = FILTER_COEFFICIENT * gyroOrientation[2] + oneMinusCoeff * accMagOrientation[2];
         }
   
         // overwrite gyro matrix and orientation with fused orientation
         // to comensate gyro drift
         gyroMatrix = getRotationMatrixFromOrientation(fusedOrientation);
         System.arraycopy(fusedOrientation, 0, gyroOrientation, 0, 3);
   
   
         // update sensor output in GUI
   //      mHandler.post(updateOreintationDisplayTask);
       }
     }
   
   
     // **************************** GUI FUNCTIONS *********************************
   
     @Override
       public void onCheckedChanged(RadioGroup group, int checkedId) {
       {
       }
     }
   
     public void updateOreintationDisplay() {
   //    switch(radioSelection) {
   //    case 0:
   //      mAzimuthView.setText(d.format(accMagOrientation[0] * 180/Math.PI) + '∞');
   //      mPitchView.setText(d.format(accMagOrientation[1] * 180/Math.PI) + '∞');
   //      mRollView.setText(d.format(accMagOrientation[2] * 180/Math.PI) + '∞');
   //      break;
   //    case 1:
   //      mAzimuthView.setText(d.format(gyroOrientation[0] * 180/Math.PI) + '∞');
   //      mPitchView.setText(d.format(gyroOrientation[1] * 180/Math.PI) + '∞');
   //      mRollView.setText(d.format(gyroOrientation[2] * 180/Math.PI) + '∞');
   //      break;
   //    case 2:
   //      mAzimuthView.setText(d.format(fusedOrientation[0] * 180/Math.PI) + '∞');
   //      mPitchView.setText(d.format(fusedOrientation[1] * 180/Math.PI) + '∞');
   //      mRollView.setText(d.format(fusedOrientation[2] * 180/Math.PI) + '∞');
   //      break;
   //    }
     }
   
     private Runnable updateOreintationDisplayTask = new Runnable() {
       public void run() {
         updateOreintationDisplay();
       }
     };
   }
   
   void setup()
   {
   }
   void draw()
   {
     background(0, 255, 0);
   
   println(fusedOrientation[0]);//??????? How can I catch this value ?
   }