looking up country names from lat long
On Mon, Dec 6, 2010 at 1:41 PM, Josh Tewksbury <tewksjj at gmail.com> wrote:
Hello - here is what I am sure is a quick question from someone new to R in spatial stats. I have a long list of lat long coordinates and I would like to do a location country check to extrapolate a country name from each lat/long point. so, for example, my data look like lat, long 14.42, -89.92 14.42, -89.75 14.42, -89.58 14.42, -89.42 14.42, -89.25 continued for the terrestrial surface of the earth. If I want to add country names, so I can use those names as tags to merge in other data, is there an easy lookup that will allow me to do that, so I end up with: lat, long, country 14.42, -89.92, Guatemala 14.42, -89.75, Guatemala 14.42, -89.58, Guatemala 14.42, -89.42, El Salvador 14.42, -89.25, Honduras
My 'geonames' package (on CRAN) can do lookups via the geonames.org web service:
GNcountryCode(lat=14.24,lng=-89.92)
$distance [1] 0 $countryName [1] "Guatemala" $countryCode [1] "GT" its being very slow at the moment though. You might have speedier responses. It can only look up one at a time, so you'll have to loop through your data frame with the usual R loop/apply-type patterns. Barry