def connect(self): 
        try:
            self.connection = pymongo.Connection(self.host, self.port)
            self.db = self.connection[self.name]
        except AutoReconnect:
            raise DatabaseException("It's not possible connect to the database")
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