Converts GeoJSON to an `sf` object
Usage
geojson_sf(
geojson,
expand_geometries = FALSE,
input = NULL,
wkt = NULL,
crs = NULL,
proj4string = NULL,
buffer_size = 1024
)Arguments
- geojson
string or vector of GeoJSON, or a URL or file pointing to a geojson file
- expand_geometries
logical indicating whether to unnest GEOMETRYCOLLECTION rows. see details
- input
user input for coordinate reference system object
- wkt
well-known text for coordinate reference system object
- crs
deprecated. coordinate reference system. See Details
- proj4string
deprecated. proj4string. See Details
- buffer_size
size of buffer used when reading a file from disk. Defaults 1024
Details
specifying expand_geometries = TRUE will expand individual GEOMETRYCOLLECTION
geometries to their own row in the resulting `sf` object. If the geometries are part
of a Feature (i.e., with properties), the properties will be repeated on each row.
The GEOMETRYCOLLECTION information is not kept when using expand_geometries = TRUE. Therefore,
it is not possible to reconstruct the GEOMETRYCOLLECTION after unnesting it.
Geojson specification RFC7946 https://datatracker.ietf.org/doc/html/rfc7946#page-12 says all CRS should be the World Geodetic System 1984 (WGS 84) [WGS84] datum, with longitude and latitude units of decimal degrees. This is equivalent to the coordinate reference system identified by the Open Geospatial Consortium (OGC) URN urn:ogc:def:crs:OGC::CRS84
geojson_sfc and geojson_sf automatically set the CRS to WGS 84.
The fields input and wkt let you to overwrite the defaults.
Examples
## character string of GeoJSON
## load 'sf' for print methods
# library(sf)
geojson <- '{ "type" : "Point", "coordinates" : [0, 0] }'
geojson_sf(geojson)
#> geometry
#> 1 0, 0
if (FALSE) { # \dontrun{
## GeoJSON at a url
myurl <- "http://eric.clst.org/assets/wiki/uploads/Stuff/gz_2010_us_050_00_500k.json"
sf <- geojson_sf(myurl)
} # }