R: Geojson to sf

geojson_sf {geojsonsf} | R Documentation

## Geojson to sf

### Description

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://tools.ietf.org/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)

    ## Not run:
    ## GeoJSON at a url
    myurl <- "http://eric.clst.org/assets/wiki/uploads/Stuff/gz_2010_us_050_00_500k.json"
    sf <- geojson_sf(myurl)

    ## End(Not run)

[Package geojsonsf version 2.0.1 Index]