geojsonio (version 0.11.3)

geojson_sp: Convert objects to spatial classes

Description

Convert objects to spatial classes

Usage

geojson_sp(x, disambiguateFIDs = FALSE, stringsAsFactors = FALSE, ...)

Value

A spatial class object, see Details.

Arguments

x

Object of class geo_list, geo_json, string, or json

disambiguateFIDs

Ignored, and will be removed in a future version. Previously was passed to rgdal::readOGR(), which is no longer used.

stringsAsFactors

Convert strings to Factors? Default FALSE.

...

Further args passed on to sf::st_read()

Details

The spatial class object returned will depend on the input GeoJSON. Sometimes you will get back a SpatialPoints class, and sometimes a SpatialPolygonsDataFrame class, etc., depending on what the structure of the GeoJSON.

The reading and writing of the CRS to/from geojson is inconsistent. You can directly set the CRS by passing a valid PROJ4 string or epsg code to the crs argument in sf::st_read()

Examples

if (FALSE) {
library(sp)

# geo_list ------------------
## From a numeric vector of length 2 to a point
vec <- c(-99.74, 32.45)
geojson_list(vec) %>% geojson_sp()

## Lists
## From a list
mylist <- list(
  list(latitude = 30, longitude = 120, marker = "red"),
  list(latitude = 30, longitude = 130, marker = "blue")
)
geojson_list(mylist) %>% geojson_sp()
geojson_list(mylist) %>%
  geojson_sp() %>%
  plot()

## From a list of numeric vectors to a polygon
vecs <- list(c(100.0, 0.0), c(101.0, 0.0), c(101.0, 1.0), c(100.0, 1.0), c(100.0, 0.0))
geojson_list(vecs, geometry = "polygon") %>% geojson_sp()
geojson_list(vecs, geometry = "polygon") %>%
  geojson_sp() %>%
  plot()

# geo_json ------------------
## from point
geojson_json(c(-99.74, 32.45)) %>% geojson_sp()
geojson_json(c(-99.74, 32.45)) %>%
  geojson_sp() %>%
  plot()

# from featurecollectino of points
geojson_json(us_cities[1:2, ], lat = "lat", lon = "long") %>% geojson_sp()
geojson_json(us_cities[1:2, ], lat = "lat", lon = "long") %>%
  geojson_sp() %>%
  plot()

# Set the CRS via the crs argument
geojson_json(us_cities[1:2, ], lat = "lat", lon = "long") %>%
  geojson_sp(crs = "+init=epsg:4326")

# json ----------------------
x <- geojson_json(us_cities[1:2, ], lat = "lat", lon = "long")
geojson_sp(x)

# character string ----------------------
x <- unclass(geojson_json(c(-99.74, 32.45)))
geojson_sp(x)
}