Nothing
Encode and decode the Google Encoded Polyline Algorithm Format
Encoding
> coords <- data.frame(lat = c(38.5, 40.7, 43.252),
+ lon = c(-120.2, -120.95, -126.453))
> encpoly <- encodePolyline(coords)
> encpoly
[1] "_p~iF~ps|U_ulLnnqC_mqNvxq`@"
Decoding
> coords <- decodePolyline(enc_polyline = "_p~iF~ps|U_ulLnnqC_mqNvxq`@")
> coords
lat lon
1 38.500 -120.200
2 40.700 -120.950
3 43.252 -126.453
Mostly a translation of http://github.com/mthh/polyline_ggl/ (itself a modest translation (i.g no GeoJSON wrapper, etc.) of other well known available implementations such as Node.js Mapbox one)
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