State boundaries (contemporary and historical)

Get the current (2019) boundaries for U.S states from the U.S. Census Bureau, or get historical state boundaries for dates between 3 September 1783 and 31 December 2000.

Usage

us_states(map_date = NULL, resolution = c("low", "high"), states = NULL)

Arguments

map_date

The date of the boundaries as some object coercible to a date with as.Date(); the easiest option is a character vector following the ISO 8601 data format. If NULL (the default) the contemporary boundaries will be returned.

resolution

The resolution of the map.

states

A character vector of state or territory names or abbreviations. Only boundaries for those states/territories will be returned. If NULL, all boundaries will be returned.

Value

An sf object.

See also

For documentation of and citation to the underlying shapefiles for contemporary data from the U.S. Census Bureau, see census_boundaries documentation in the USAboundariesData package. For documentation of and citation to the underlying shapefiles for historical data from the Atlas of Historical County Boundaries, see the ahcb_boundaries documentation in the USAboundariesData package.

Examples

contemporary_us <- us_states()
if (require(USAboundariesData) && require(sf)) {
  historical_us <- us_states("1820-07-04")
  contemporary_ne <- us_states(
    states = c(
      "Massachusetts",
      "Vermont",
      "Maine",
      "New Hampshire",
      "Rhode Island",
      "Connecticut"
    )
  )
  historical_ne <- us_states(
    as.Date("1805-03-12"),
    states = c(
      "Massachusetts",
      "Vermont",
      "Maine",
      "New Hampshire",
      "Rhode Island",
      "Connecticut"
    ),
    resolution = "high"
  )
  plot(st_geometry(contemporary_us))
  plot(st_geometry(historical_us))
  plot(st_geometry(contemporary_ne))
  plot(st_geometry(historical_ne))
}