I am trying to use the geojsonio package to write some geojson files from data.frames pulled from some other R packages.
library(ggplot2)
library(geojsonio)
us_state <- map_data('state')
geojson_write(us_state,
geometry="polygon",
grouping="group",
file="path/file.geojson")
The problem I'm having is with the geometry=polygon argument. I get the following error:
Error in .subset2(x, i, exact = exact) :
attempt to select less than one element in integerOneIndex
When geometry=point it works fine, but then of course I have just a million separate points instead of state polygons in the geojson file.
Any thoughts?
Edit:
I can get a working geojson file if I use file<-geojson_json(data.frame) first, then geojson_write(file)
You just need to use the right parameter name group, not grouping. Since the function has a ..., a wrong parameter name can be passed in and not throw any errors/etc.
library(ggplot2)
library(geojsonio)
us_state <- map_data('state')
geojson_write(us_state,
geometry = "polygon",
group = "group",
file = "file.geojson")
#> {
#> "type": "FeatureCollection",
#>
#> "features": [
#> { "type": "Feature", "id": 0, "properties": { "dummy": 0.000000 }, "geometry": { "type": "MultiPolygon", "coordinates": [ [ [ [ -87.462005615234375, 30.389680862426758 ], [ -87.484931945800781, 30.372491836547852 ], [ -87.525032043457031, 30.372491836547852 ], [ -87.53076171875, 30.332386016845703 ], [ -87.570869445800781, 30.326654434204102 ], [ -87.588058471679688, 30.326654434204102 ], [ -87.593788146972656, 30.309467315673828 ], [ -87.593788146972656, 30.286548614501953 ], [ -8
#> ... cutoff