tiger_urban_area_sf {RcensusPkg} | R Documentation |
tiger_urban_area_sf
Description
This function performs three tasks:
Download to an output directory a zip file from the TIGER/Line Shapefiles database.
Unzip the zip file and locate the shape file of interest.
Read and convert the shape file to a simple feature object.
The function returns geometries for the Census Bureau's defined "urban areas" across the entire US
Usage
tiger_urban_area_sf(
output_dir = tempdir(),
delete_files = TRUE,
vintage = 2020,
general = FALSE,
resol = "500k",
set_crs = NULL,
transform_crs = NULL,
sf_info = FALSE,
do_progress = FALSE,
shapefile = NULL,
datafile = NULL,
datafile_key = NULL,
sf_key = "GEOID",
check_na = FALSE
)
Arguments
output_dir |
A full directory path where the shapefile and its associated files will be downloaded.
The default is the directory defined by the value returned by |
delete_files |
A logical which if |
vintage |
A numeric that sets the vintage of interest. The default is 2020. |
general |
A logical which if |
resol |
If 'general' is |
set_crs |
A numeric or character string which if non-NULL calls |
transform_crs |
A numeric or character string which if non-NULL calls |
sf_info |
A logical which if |
do_progress |
A logical which if TRUE displays a progress bar during the download. |
shapefile |
A full file path to a shapefile folder with its unzipped files to be processed instead of downloading. |
datafile |
A dataframe containing data that should be joined with this function's resultant simple feature object. |
datafile_key |
The column name from 'datafile' dataframe used to key with the 'sf_key' column of the resultant simple feature dataframe. |
sf_key |
The column from the resultant dataframe used to key with the 'datafile' dataframe. |
check_na |
A logical which if |
Details
Returns simple feature(sf) of the Census Bureau's defined "urban area" boundary related geometric polygons, provided by the US Census Bureau's TIGER/Line Shapefiles database. See Simple Features for R for more information on simple features.
A more generalized, recognizable version of the CBSA geometries that has less download size is also available. For more information on cartographic boundary files see Cartographic Boundary File Description. These files are available for vintages greater than 2009 with resolution 1:500k, 1:5m, 1:20m meters. For descriptive information on CBSA see About.
The function returns the simple feature object which can easily be mapped (see RplotterPkg::create_sf_plot()) or joined with US Census Bureau demographic data. To help incorporate data files, this function has a 'datafile' parameter which will be joined with the resultant simple feature object. The only requirement is that a common "key" for joining exist between the data dataframe and the simple feature dataframe.
Value
A data frame object of class sf
Examples
library(downloader)
library(sf)
library(data.table)
library(withr)
library(RcensusPkg)
# Get the defined urban areas for 2019
# Define a temporary, self deleting output folder for the downloaded shapefiles
output_dir <- withr::local_tempdir()
if(!dir.exists(output_dir)){
dir.create(output_dir)
}
us_urban_areas_sf <- RcensusPkg::tiger_urban_area_sf(
output_dir = output_dir,
vintage = 2019,
general = TRUE,
delete_files = FALSE
)