tigris (version 0.8.2)

roads: Download a roads shapefile into R

Description

From the Census Bureau: "The content of the all roads shapefile includes primary roads, secondary roads, local neighborhood roads, rural roads, city streets, vehicular trails (4WD), ramps, service drives, walkways, stairways, alleys, and private roads."

Usage

roads(state, county, year = NULL, ...)

Arguments

state

The two-digit FIPS code of the state of the county you'd like to download the roads for. Can also be state name or abbreviation (case-insensitive).

county

The three-digit FIPS code of the county you'd like the roads for. Can also be a county name.

year

the data year (defaults to 2017).

...

arguments to be passed to the underlying `load_tiger` function, which is not exported. Options include class, which can be set to "sp" (the default) or "sf" to request sp or sf class objects, and refresh, which specifies whether or not to re-download shapefiles (defaults to FALSE).

See Also

http://www2.census.gov/geo/pdfs/maps-data/data/tiger/tgrshp2015/TGRSHP2015_TechDoc.pdf

Other transportation functions: address_ranges, primary_roads, primary_secondary_roads, rails

Examples

# NOT RUN {
library(tigris)
library(ggplot2)
library(ggthemes)
library(rgeos)
library(sp)

roads <- roads("Maine", "031")

# for ggplot, we need to simplify the lines otherwise it'll take
# forever to plot. however, gSimplify whacks the SpatialLinesDataFrame
# so we need to re-bind the data from the original object to it so
# we can use "fortify"

roads_simp <- gSimplify(roads, tol=1/200, topologyPreserve=TRUE)
roads_simp <- SpatialLinesDataFrame(roads_simp, roads@data)

roads_map <- fortify(roads_simp) # this takes a bit

gg <- ggplot()
gg <- gg + geom_map(data=roads_map, map=roads_map,
                    aes(x=long, y=lat, map_id=id),
                    color="black", fill="white", size=0.25)
gg <- gg + coord_map()
gg <- gg + theme_map()
gg
# }