You might be looking for the usmap package: CRAN | GitHub | Website
usmapdata is a container package for the map data frame
used in the usmap package.
This data has been extracted to keep usmap small and easier
to maintain, while allowing the ability to keep the US map data frame
updated as often as possible (independently of usmap
updates).
This package and repository will only contain functions and data
relevant to the actual map and FIPS data used to draw the map in the
usmap package. All other functions, including FIPS and
mapping convenience functions, will be contained in the
usmap repository.
The map data files that we use to plot the maps in R are located in
the inst/extdata folder. They are generated from shapefiles
published by the US Census Bureau.
Data files for maps and FIPS codes at both the state and county levels
are included.
The Cartographic
Boundary Files are used for mapping in
usmap—specifically the 1:20m scale files. This low
resolution allows for small file sizes while still allowing enough
detail for simple choropleths. The file description can be read here.
Shapefiles are updated yearly by the US Census Bureau. This
repository contains scripts which periodically check for new shapefiles
and update the data in the package accordingly. For more details see the
data-raw
directory.
This package should only be installed if you intend to manipulate the
US mapping data frame, which contains coordinates to draw the US state
and county boundaries. If you’re interested in plotting data on a US
map, use the usmap package.
📦 To install from CRAN (recommended), run the following code in an R console:
install.packages("usmapdata")⚠️ The developer build may be unstable and not function correctly, use with caution.
To install the package from this repository, run the following code in an R console:
# install.package("devtools")
devtools::install_github("pdil/usmapdata")This method will provide the most recent developer build of
usmapdata.
To begin using usmapdata, import the package using the
library command:
library(usmapdata)usmap uses the US
National Atlas Equal Area coordinate system:
sf::st_crs(9311)
r #> Coordinate Reference System: #> User input: EPSG:9311 #> wkt: #> PROJCRS["NAD27 / US National Atlas Equal Area", #> BASEGEOGCRS["NAD27", #> DATUM["North American Datum 1927", #> ELLIPSOID["Clarke 1866",6378206.4,294.978698213898, #> LENGTHUNIT["metre",1]]], #> PRIMEM["Greenwich",0, #> ANGLEUNIT["degree",0.0174532925199433]], #> ID["EPSG",4267]], #> CONVERSION["US National Atlas Equal Area", #> METHOD["Lambert Azimuthal Equal Area (Spherical)", #> ID["EPSG",1027]], #> PARAMETER["Latitude of natural origin",45, #> ANGLEUNIT["degree",0.0174532925199433], #> ID["EPSG",8801]], #> PARAMETER["Longitude of natural origin",-100, #> ANGLEUNIT["degree",0.0174532925199433], #> ID["EPSG",8802]], #> PARAMETER["False easting",0, #> LENGTHUNIT["metre",1], #> ID["EPSG",8806]], #> PARAMETER["False northing",0, #> LENGTHUNIT["metre",1], #> ID["EPSG",8807]]], #> CS[Cartesian,2], #> AXIS["easting (X)",east, #> ORDER[1], #> LENGTHUNIT["metre",1]], #> AXIS["northing (Y)",north, #> ORDER[2], #> LENGTHUNIT["metre",1]], #> USAGE[ #> SCOPE["Statistical analysis."], #> AREA["United States (USA) - onshore and offshore."], #> BBOX[15.56,167.65,74.71,-65.69]], #> ID["EPSG",9311]]
This coordinate
reference system (CRS) can also be obtained with
usmap::usmap_crs().
The code used to generate the map files was based on this blog post by Bob Rudis: Moving The Earth (well, Alaska & Hawaii) With R