More geo coding

I got the airport data nailed down, at least all the stuff I need for iPhone CoPilot (which unlike the other databases I provide doesn’t care about communications frequencies or runways). And now I’m looking at “waypoints”, the points in space, sometimes defined by the intersection of a specific radial or bearing from this navigation aid and a specific radial or bearing from that navigation aid, sometimes a distance and radial from one navigation aid, or in the case of GPS instrument approaches and air routes, just points in space.

The difficulty with waypoints is that their definition in the file doesn’t have any sort of location information other than latitude and longitude, which means I have to hit the geonames server for every one (and so far I’ve gone over my hourly limit with them multiple times while testing this code), and that sometimes they, unlike airports, can be out in the middle of the ocean somewhere. So the geonames “countrySubdivision” service just says “I have no idea what country this is in”.

Unfortunately, my code doesn’t like it when a point isn’t in a country. I need to assign every point a 2 letter country code (I use the FIPS 10.4 code instead of ISO-3166-1 because my first world data came from DAFIF, which used FIPS 10.4 and I stuck with it. I’d probably switch to ISO-3166-1 except I have no idea how to do it painlessly.)

In my program to load FAA data, I do some messing around trying to map the country names they use to FIPS 10.4, and sometimes I’ve done some things I’m not proud of, like mapping “French West Indies” to “GP” (the code for Guadeloupe, which is just one of the four territories that make up the French West Indies) or “Trust Territories” to “JQ” (the code for Johnston Atoll) – that one is really dodgy because the “Trust Territories” were broken down into the Republic of the Marshall Islands (“RM”), the Federated States of Micronesia (“FM”), The Commonwealth of the Northern Mariana Islands (“CQ”) and the Republic of Palau (“PS”). Actually if I looked through the FAA data these days, I’d probably find they never use the name “Trust Territories” any more. Another one that comes up is the United States Minor Outlying Islands, which has an ISO-3166-1 code “UM”, but which consists of 9 separate “insular areas” that have their own FIPS 10.4 codes.

So my thought was to ask the geonames “ocean” service what body of water these points is, and then make up a phoney country code for each ocean. Unfortunately there aren’t just a few oceans, there are are dozens of them – everything from the Arabian Sea to the South Pacific Ocean. So many that I can’t come up with semi-mnemonic identifiers for them. So using the fact that FIPS 10.4 codes never start with O or X, I just went though and assigned anything with “Ocean” in the name a code starting with “O” and anything else a code starting with “X”. It sucks, but it will work. Sort of. I hope.

The long term solution is that separate the code I use for iPhone CoPilot further away from the other navaid.com code, and not require a non-null country code in iPhone CoPilot. Also try to migrate to ISO-3166-1 country codes.