final List<Point2D> data = new ArrayList<>();
for (double x = 0; x < 20; x += 0.25) {
final double y = Math.sin(x / 2) + Math.sin(x / 1.26);
final List<Point2D> data = new ArrayList<>();
for (double x = 0; x < 20; x += 0.25) {
final double y = Math.sin(x / 2) + Math.sin(x / 1.26);