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我已经为罗盘实现了以下代码，但是当我将以下代码中的值（由 azimut 返回）与 iphone 罗盘应用程序进行比较时，似乎我在阅读时偏离了 90 度。我需要从其他任何地方获取值吗传感器..？？。此外，即使在应用低通滤波器后，似乎也有相当多的抖动。对此有什么建议..？？

public class CompassExample4Activity extends Activity implements SensorEventListener{

private SensorManager mSensorManager;
CompassView mCompassView;
Sensor accelerometer;
Sensor magnetometer;
float azimut;
float[] mGravity;
float[] mGeomagnetic;
static final float ALPHA = 0.2f;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mCompassView = new CompassView(this);
    setContentView(mCompassView);

    mSensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
    accelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
    magnetometer = mSensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
}

@Override
public void onResume() {
    super.onResume();
    mSensorManager.registerListener(this, accelerometer, SensorManager.SENSOR_DELAY_UI);
    mSensorManager.registerListener(this, magnetometer, SensorManager.SENSOR_DELAY_UI);
}

@Override
public void onPause() {
    super.onPause();
    mSensorManager.unregisterListener(this);
}

@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
    // TODO Auto-generated method stub

}

@Override
public void onSensorChanged(SensorEvent event) {
    // TODO Auto-generated method stub
    if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER)
          mGravity = lowPass(event.values, mGravity);
    if (event.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD)
          mGeomagnetic = lowPass(event.values, mGeomagnetic);

    if (mGravity != null && mGeomagnetic != null) {
          float R[] = new float[9];
          float I[] = new float[9];
          boolean success = SensorManager.getRotationMatrix(R, I, mGravity, mGeomagnetic);
          // Correct if screen is in Landscape
          SensorManager.remapCoordinateSystem(R, SensorManager.AXIS_X,
                    SensorManager.AXIS_Z, R);

          if (success) {
            float orientation[] = new float[3];
            SensorManager.getOrientation(R, orientation);
            float azimut = orientation[0]; // orientation contains: azimut, pitch and roll
            mCompassView.updateDirection(azimut*360/(2*3.14159f));
            //mCompassView.updateDirection(azimuth);
          }
     }
}

protected float[] lowPass( float[] input, float[] output ) {
    if ( output == null ) return input;

    for ( int i=0; i<input.length; i++ ) {
        output[i] = output[i] + ALPHA * (input[i] - output[i]);
    }
    return output;
}

}

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