for (int i = 0; i < angles.length; ++i) {
problem.addAngularMeasurement(3.0e7, angles[i][0], angles[i][1]);
};
LevenbergMarquardtEstimator estimator = new LevenbergMarquardtEstimator();
estimator.estimate(problem);
System.out.println("initial position: " + problem.getX0() + " " + problem.getY0());
System.out.println("velocity: " + problem.getVx0() + " " + problem.getVy0());
} catch (EstimationException ee) {
System.err.println(ee.getMessage());