Is it possible to read geoJSON or topoJSON file in R to draw a choropleth map?

Question

topoJSON and geoJSON files are know very common for drawing maps on the internet. Is it possible to import them in R to draw choropleth maps?

@vrajs5 Please use `code markdown` only for code, not for parts of sentences like "choropleth maps". — S.L. Barth is on codidact.com, Jun 12 '14 at 12:10

score 26 · Accepted Answer · edited Jul 06 '16 at 15:11

26

Get the rgdal package installed. Then if:

library(rgdal)
> "GeoJSON" %in% ogrDrivers()$name
[1] TRUE

then you can do something like:

> map = readOGR("foo.json", "OGRGeoJSON")
> plot(map)

But you need GeoJSON support in your ogrDrivers list.

edited Jul 06 '16 at 15:11

marbel

answered Jun 12 '14 at 12:10

Spacedman

Thanks. Do you know if its possible to add new formats such as topojson to the ogrDrivers list ? – PAC Jun 13 '14 at 09:59
1

That's a two step process. For a brand new format, it has to be implemented in C or C++ as a "driver" for the underlying GDAL/OGR library. Secondly it has to be compiled into the GDAL/OGR library binary on your system. There is a topojson driver from GDAL 1.11 (according to wikipedia). If you dont see that then you need to upgrade some things on your machine. – Spacedman Jun 13 '14 at 10:09

1 Answers1