如何从R中的州边界获取经纬度数据

Question

Here is my problem: I need to get longitude and latitude data from the borders of the Brazilian states. With this data I can plot a map of each Brazilian state and, of course, of the whole country.

I'm quite new to R but I know it has some packages to plot maps and also to get latitude and longitude data from cities, countries, etc.

The problem is that I need latitude and longitude from the bordes of each state and not just the map. I need the data to after construct the map and I don't know if it's possible to get this sort of data in R.

Can someone help me?

Answer 1

I think that you want to download the shp file and not the r poly file. You can then simply unzip and then use the maptools package to load the shape file.

require(maptools)
brazil <- readShapeLines("BRA_adm0.shp")
plot(brazil)

This will actually produce a plot of the outline of brazil. I believe you can simply layer on the additional shp files using plot. You may have to merge the spatial lines data frames to use other graphics packages such as ggplot2.