geojsonio
converts geographic data to geojson and
topojson formats. Nothing else. We hope to do this one job very well,
and handle all reasonable use cases.
Functions in this package are organized first around what you’re working with or want to get, geojson or topojson, then convert to or read from various formats:
-
geojson_list()
/topojson_list()
- convert to GeoJSON/TopoJSON as R list format -
geojson_json()
/topojson_json()
- convert to GeoJSON/TopoJSON as JSON -
geojson_sp()
- convert output ofgeojson_list()
orgeojson_json()
to spatial objects -
geojson_read()
/topojson_read()
- read a GeoJSON/TopoJSON file from file path or URL -
geojson_write()
/topojson_write()
- write a GeoJSON/TopoJSON file locally
Each of the above functions have methods for various objects/classes,
including numeric
, data.frame
,
list
, SpatialPolygons
,
SpatialLines
, SpatialPoints
, etc.
Additional functions:
-
map_gist()
- push up a geojson or topojson file as a GitHub gist (renders as an interactive map) - See the maps with geojsonio vignette. -
map_leaf()
- create a local interactive map with theleaflet
package - See the maps with geojsonio vignette.
Install
Install rgdal - in case you can’t get it installed from binary ,
here’s what works on a Mac (change to the version of rgdal
and GDAL
you have).
install.packages("http://cran.r-project.org/src/contrib/rgdal_1.1-3.tar.gz", repos = NULL, type="source", configure.args = "--with-gdal-config=/Library/Frameworks/GDAL.framework/Versions/1.11/unix/bin/gdal-config --with-proj-include=/Library/Frameworks/PROJ.framework/unix/include --with-proj-lib=/Library/Frameworks/PROJ.framework/unix/lib")
Stable version from CRAN
install.packages("geojsonio")
Development version from GitHub
remotes::install_github("ropensci/geojsonio")
GeoJSON
Convert various formats to geojson
From a numeric
vector of length 2
as json
geojson_json(c(32.45, -99.74))
#> <FeatureCollection>
#> type: FeatureCollection
#> no. features: 1
#> features (1st 5): Point
as a list
geojson_list(c(32.45, -99.74))
#> $type
#> [1] "FeatureCollection"
#>
#> $features
#> $features[[1]]
#> $features[[1]]$type
#> [1] "Feature"
#>
#> $features[[1]]$geometry
#> $features[[1]]$geometry$type
...
From a data.frame
as json
library('maps')
data(us.cities)
geojson_json(us.cities[1:2, ], lat = 'lat', lon = 'long')
#> <FeatureCollection>
#> type: FeatureCollection
#> no. features: 2
#> features (1st 5): Point, Point
as a list
geojson_list(us.cities[1:2, ], lat = 'lat', lon = 'long')
#> $type
#> [1] "FeatureCollection"
#>
#> $features
#> $features[[1]]
#> $features[[1]]$type
#> [1] "Feature"
#>
#> $features[[1]]$geometry
#> $features[[1]]$geometry$type
...
From SpatialPolygons
class
library('sp')
poly1 <- Polygons(list(Polygon(cbind(c(-100,-90,-85,-100),
c(40,50,45,40)))), "1")
poly2 <- Polygons(list(Polygon(cbind(c(-90,-80,-75,-90),
c(30,40,35,30)))), "2")
sp_poly <- SpatialPolygons(list(poly1, poly2), 1:2)
to json
geojson_json(sp_poly)
#> <FeatureCollection>
#> type: FeatureCollection
#> no. features: 2
#> features (1st 5): Polygon, Polygon
to a list
geojson_list(sp_poly)
#> $type
#> [1] "FeatureCollection"
#>
#> $name
#> [1] "filef016f24f95e"
#>
#> $features
#> $features[[1]]
#> $features[[1]]$type
#> [1] "Feature"
...
From SpatialPoints
class
x <- c(1, 2, 3, 4, 5)
y <- c(3, 2, 5, 1, 4)
s <- SpatialPoints(cbind(x, y))
to json
geojson_json(s)
#> <FeatureCollection>
#> type: FeatureCollection
#> no. features: 5
#> features (1st 5): Point, Point, Point, Point, Point
to a list
geojson_list(s)
#> $type
#> [1] "FeatureCollection"
#>
#> $name
#> [1] "filef014e51d7de"
#>
#> $features
#> $features[[1]]
#> $features[[1]]$type
#> [1] "Feature"
...
Write geojson
library('maps')
data(us.cities)
geojson_write(us.cities[1:2, ], lat = 'lat', lon = 'long')
#> <geojson-file>
#> Path: myfile.geojson
#> From class: data.frame
Read geojson
library("sp")
file <- system.file("examples", "california.geojson", package = "geojsonio")
out <- geojson_read(file, what = "sp")
plot(out)
Topojson
To JSON
topojson_json(c(-99.74,32.45))
#> {"type":"Topology","objects":{"foo":{"type":"GeometryCollection","geometries":[{"type":"Point","coordinates":[-99.74,32.45]}]}},"arcs":[],"bbox":[-99.74,32.45,-99.74,32.45]}
To a list
library(sp)
x <- c(1,2,3,4,5)
y <- c(3,2,5,1,4)
s <- SpatialPoints(cbind(x,y))
topojson_list(s)
#> $type
#> [1] "Topology"
#>
#> $objects
#> $objects$foo
#> $objects$foo$type
#> [1] "GeometryCollection"
#>
#> $objects$foo$geometries
#> $objects$foo$geometries[[1]]
#> $objects$foo$geometries[[1]]$type
#> [1] "Point"
#>
#> $objects$foo$geometries[[1]]$coordinates
#> [1] 1 3
#>
#> $objects$foo$geometries[[1]]$properties
#> $objects$foo$geometries[[1]]$properties$dat
#> [1] 1
#>
...
Read from a file
file <- system.file("examples", "us_states.topojson", package = "geojsonio")
out <- topojson_read(file)
summary(out)
#> id geometry
#> Length:51 MULTIPOLYGON:51
#> Class :character epsg:NA : 0
#> Mode :character
Read from a URL
url <- "https://raw.githubusercontent.com/shawnbot/d3-cartogram/master/data/us-states.topojson"
out <- topojson_read(url)
Or use as.location()
first
(loc <- as.location(file))
#> <location>
#> Type: file
#> Location: /usr/local/lib/R/site-library/geojsonio/examples/us_states.topojson
out <- topojson_read(loc)