@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		ChangeIn other = (ChangeIn) obj;
		if (Double.doubleToLongBits(dx) != Double.doubleToLongBits(other.dx))
			return false;
		if (Double.doubleToLongBits(dy) != Double.doubleToLongBits(other.dy))
			return false;
		return true;
	}