def test_order(self):
        assert (event.Priority.PRE_CORE
                > event.Priority.CORE
                > event.Priority.POST_CORE
                > event.Priority.PRE_DEFAULT
                > event.Priority.DEFAULT
                > event.Priority.POST_DEFAULT)
def getAp1(self):
        ret = math.acos(((self.getLenp2() * self.getLenp2() + self.getLenp3() * self.getLenp3()) - self.getLenp1() * self.getLenp1()) / (2* self.getLenp2() * self.getLenp3()))
        return ret