ggplot2 (version 1.0.0)

borders: Create a layer of map borders.

Description

Create a layer of map borders.

Usage

borders(database = "world", regions = ".", fill = NA, colour = "grey50",
  ...)

Arguments

database

map data, see map for details

regions

map region

fill

fill colour

colour

border colour

...

other arguments passed onto geom_polygon

Examples

if (require("maps")) {

ia <- map_data("county", "iowa")
mid_range <- function(x) mean(range(x))
library(plyr)
seats <- ddply(ia, .(subregion), colwise(mid_range, .(lat, long)))
ggplot(ia, aes(long, lat)) +
  geom_polygon(aes(group = group), fill = NA, colour = "grey60") +
  geom_text(aes(label = subregion), data = seats, size = 2, angle = 45)

data(us.cities)
capitals <- subset(us.cities, capital == 2)
ggplot(capitals, aes(long, lat)) +
  borders("state") +
  geom_point(aes(size = pop)) +
  scale_size_area()

}