hexbin statebins in R via GeoJSON

gistfile1.txt

library(rgdal)
library(rgeos)
library(ggplot2)

# get GeoJSON from https://team.cartodb.com/u/andrew/tables/andrew.us_states_hexgrid/public/map

# Read in GeoJSON ---------------------------------------------------------

us <- readOGR("us_states_hexgrid.geojson", "OGRGeoJSON")

# Get centers of polygns for label placement ------------------------------

centers <- cbind.data.frame(data.frame(gCentroid(us, byid=TRUE), id=us@data$iso3166_2))

# Convert base shapefile into something ggplot can handle -----------------

us_map <- fortify(us, region="iso3166_2")

gg <- ggplot()

# Plot base map -----------------------------------------------------------

gg <- gg + geom_map(data=us_map, map=us_map,
                    aes(x=long, y=lat, map_id=id),
                    color="white", size=0.5)

# Plot filled polygons ----------------------------------------------------

gg <- gg + geom_map(data=us@data, map=us_map,
                    aes(fill=bees, map_id=iso3166_2))

# Overlay borders without ugly line on legend -----------------------------

gg <- gg + geom_map(data=us@data, map=us_map,
                    aes(map_id=iso3166_2),
                    fill="#ffffff", alpha=0, color="white",
                    show_guide=FALSE)

# Place state name in center ----------------------------------------------

gg <- gg + geom_text(data=centers, aes(label=id, x=x, y=y), color="white", size=4)

# ColorBrewer scale; using distiller for discrete vs continuous -----------

gg <- gg + scale_fill_distiller(palette="RdPu", na.value="#7f7f7f")

# coord_map mercator works best for the display ---------------------------

gg <- gg + coord_map()

# Remove chart junk for the “map" -----------------------------------------

gg <- gg + labs(x=NULL, y=NULL)
gg <- gg + theme_bw()
gg <- gg + theme(panel.border=element_blank())
gg <- gg + theme(panel.grid=element_blank())
gg <- gg + theme(axis.ticks=element_blank())
gg <- gg + theme(axis.text=element_blank())
gg