def test_sees(self): sat1 = Satellite('SAT1', 0, 0, 1 + earth.radius * sqrt(2)) sat2 = Satellite('SAT2', 0, pi, 1 + earth.radius * sqrt(2)) sat3 = Satellite('SAT2', 0, pi/2, 1 + earth.radius * sqrt(2)) self.assertFalse(sat1.sees(sat2)) self.assertTrue(sat1.sees(sat3)) self.assertTrue(sat2.sees(sat3))