Python sensor_msgs.msg 模块，NavSatFix() 实例源码

def update_telemetry(navsat_msg, compass_msg):
    """Telemetry subscription callback.

    Args:
        navsat_msg: sensor_msgs/NavSatFix message.
        compass_msg: std_msgs/Float64 message in degrees.
    """
    try:
        client.post_telemetry(navsat_msg, compass_msg)
    except (ConnectionError, Timeout) as e:
        rospy.logwarn(e)
        return
    except (ValueError, HTTPError) as e:
        rospy.logerr(e)
        return
    except Exception as e:
        rospy.logfatal(e)
        return

def test_post_telemetry(self):
        """Tests posting telemetry data through client."""
        # Set up test data.
        url = "http://interop"
        client_args = (url, "testuser", "testpass", 1.0)

        with InteroperabilityMockServer(url) as server:
            # Setup mock server.
            server.set_root_response()
            server.set_login_response()
            server.set_telemetry_response()

            # Connect client.
            client = InteroperabilityClient(*client_args)
            client.wait_for_server()
            client.login()
            client.post_telemetry(NavSatFix(), Float64())

def test_telemetry_serializer(self):
        """Tests telemetry serializer."""
        # Set up test data.
        navsat = NavSatFix()
        navsat.latitude = 38.149
        navsat.longitude = -76.432
        navsat.altitude = 30.48
        compass = Float64(90.0)

        data = serializers.TelemetrySerializer.from_msg(navsat, compass)
        altitude_msl = serializers.meters_to_feet(navsat.altitude)

        # Compare.
        self.assertEqual(data["latitude"], navsat.latitude)
        self.assertEqual(data["longitude"], navsat.longitude)
        self.assertEqual(data["altitude_msl"], altitude_msl)
        self.assertEqual(data["uas_heading"], compass.data)

def _subscribe(self):
        assert self.state_subscriber is None
        assert self.position_subscriber is None
        self.state_subscriber = rospy.Subscriber(
            '%s/mavros/state' % self.namespace, State,
            callback=self._state_callback)
        self.position_subscriber = rospy.Subscriber(
            '%s/mavros/global_position/global' % self.namespace, NavSatFix,
            callback=self._position_callback)