def test_can_observe(): """Test can_observe function used in LRB paper.""" point = Point(1.0, 1.0, 1.0, 1.0) spacetime_loc = Point(0.0, 0.0, 0.0, 0.0) worldline_start = Point(-10.0, -10.0, -10.0, -10.0) worldline_end = Point(10.0, 10.0, 10.0, 10.0) assert point.can_observe(spacetime_loc, worldline_start, worldline_end) spacetime_loc = Point(1.0, 1.0, 1.0, 1.0) assert point.can_observe(spacetime_loc, worldline_start, worldline_end)