Reverse geocoding API in sf format

Generates an address from latitude and longitude (latitudes in \(\left[-90, 90 \right]\) and longitudes in \(\left[-180, 180 \right]\)), and returns the spatial object associated with the query using sf. See reverse_geo_lite() for retrieving the data in tibble format.

Usage

reverse_geo_lite_sf(
  lat,
  long,
  address = "address",
  full_results = FALSE,
  return_coords = TRUE,
  verbose = FALSE,
  nominatim_server = "https://nominatim.openstreetmap.org/",
  progressbar = TRUE,
  custom_query = list(),
  points_only = TRUE
)

Arguments

lat: Latitude values in numeric format. Must be in the range \(\left[-90, 90 \right]\).
long: Longitude values in numeric format. Must be in the range \(\left[-180, 180 \right]\).
address: Address column name in the output data (default "address").
full_results: Returns all available data from the API service. If FALSE (default), only latitude, longitude and address columns are returned. See also return_addresses.
return_coords: Return input coordinates with results if TRUE.
verbose: If TRUE, detailed logs are output to the console.
nominatim_server: The URL of the Nominatim server to use. Defaults to "https://nominatim.openstreetmap.org/".
progressbar: Logical. If TRUE displays a progress bar to indicate the progress of the function.
custom_query: API-specific parameters to be used, passed as a named list, for example list(zoom = 3). See Details.
points_only: Logical TRUE/FALSE. Whether to return only spatial points (TRUE, which is the default) or potentially other shapes as returned by the Nominatim API (FALSE). See About geometry types.

Value

A sf object with the results.

Details

See https://nominatim.org/release-docs/latest/api/Reverse/ for additional parameters to be passed to custom_query.

About zooming

Use the option custom_query = list(zoom = 3) to adjust the output. Some zoom levels correspond to these address details:

zoom	address_detail
`3`	country
`5`	state
`8`	county
`10`	city
`14`	suburb
`16`	major streets
`17`	major and minor streets
`18`	building

About geometry types

The parameter points_only specifies whether the function results will be points (all Nominatim results are guaranteed to have at least point geometry) or possibly other spatial objects.

Note that when points_only = FALSE, the type of geometry returned depends on the object being geocoded. Administrative areas, major buildings and the like will be returned as polygons, rivers, roads and similar features will be returned as lines, and amenities may still be returned as points.

The function is vectorized, allowing multiple addresses to be geocoded, with points_only = FALSE, multiple geometry types may be returned.

Examples

# \donttest{
library(ggplot2)

# Colosseum coordinates
col_lon <- 12.49309
col_lat <- 41.89026

# Colosseum as polygon
col_sf <- reverse_geo_lite_sf(
  lat = col_lat,
  lon = col_lon,
  points_only = FALSE
)

dplyr::glimpse(col_sf)
#> Rows: 1
#> Columns: 4
#> $ address  <chr> "Piazza del Colosseo, Celio, Municipio Roma I, Roma, Roma Cap…
#> $ lat      <dbl> 41.89026
#> $ lon      <dbl> 12.49309
#> $ geometry <POINT [°]> POINT (12.49333 41.89014)

if (!all(sf::st_is_empty(col_sf))) {
  ggplot(col_sf) +
    geom_sf()
}


# City of Rome: same coordinates with zoom 10

rome_sf <- reverse_geo_lite_sf(
  lat = col_lat,
  lon = col_lon,
  custom_query = list(zoom = 10),
  points_only = FALSE
)

dplyr::glimpse(rome_sf)
#> Rows: 1
#> Columns: 4
#> $ address  <chr> "Roma, Roma Capitale, Lazio, Italia"
#> $ lat      <dbl> 41.89026
#> $ lon      <dbl> 12.49309
#> $ geometry <MULTIPOLYGON [°]> MULTIPOLYGON (((12.23447 41...

if (!all(sf::st_is_empty(rome_sf))) {
  ggplot(rome_sf) +
    geom_sf()
}

# }