oolive/traffic - results in feet and knots...

Hi,
After some trouble installing the traffic dependencies (seems to collide with other geos implementations), I got the traffic application running. Work very nice but I still have some questions.

Q1: In the documentation I find that all data is stored in meters (I as experienced with the OpenSky python API. Now I find that the opensky.history function returns the data in feet and knots. The traffic.conf doesn't mention any setting about metric output. Is there a way the force the opensky.history function to return metric output?

Q2: the resulting data seems a little dirty (querying summer of 2016 at this moment). The timestamp and the 'last postion' show that the position is updated at a lower frequency than the ADS-B message. Any suggestions on filtering these messages out? Is there an 'age of gps position' available?

Q3: to reduce the amount of data, it would be nice to query the data in a 10 second resolution only. Any options there?

Q4: since I want to calculate distance to dwellings, I need the data in a cartesian reference system. I am doing it in post-processing now, but retrieving the data in a predefined cartesian reference system would be nice. There seem to be some options there in the visualization functions (but I didn't dig in yet). Similar options at the level of the query?

Thanks,
Luc

Hello,

Q1: Indeed, ADSB broadcasts data in imperial units and opensky converts them to metric system. That's a choice, and it is a bit uncomfortable for ATM research to have metric system. The option is in the code in a static submethod, I just need to add it to opensky.history(). See status in github.com/xoolive/traffic/issues/83

Q2: Good point. The last_position column refers to that. You can use the Flight.handle_last_position() (not documented but it's there!) method to put NaN values where need be. Fliht.resample() automatically calls this method first. traffic-viz.github.io/traffic.core.flight.html

Q3: No method yet (and to be honest, I wouldn't use it...). But if you can write the proper SQL request, we can include the option. Pull requests open

Q4: Not that I am aware of. Please tell me if you find a way.

If you have more questions, please post issues to the github page (it's faster for me to be aware of questions!), and questions would benefit fellow users.

Xavier

Thanks for the quick reply. I will check the flight options. I think my post-processing will be a little bit to specific to include it in Traffic.
Greetings,
Luc