Get started with nominatimlite

The goal of nominatimlite is to provide a light interface for geocoding addresses, based on the Nominatim API. It also allows to load spatial objects using the sf package.

Full site with examples and vignettes on https://dieghernan.github.io/nominatimlite/

What is Nominatim?

Nominatim is a tool to search OpenStreetMap data by name and address (geocoding) and to generate synthetic addresses of OSM points (reverse geocoding).

Why nominatimlite?

The main goal of nominatimlite is to access the Nominatim API while avoiding the dependency on curl. In some situations, curl may not be available or accessible, so nominatimlite uses base functions to overcome this limitation.

Recommended packages

There are other packages that are more complete and mature than nominatimlite and provide similar features:

• tidygeocoder (Cambon et al. 2021): Allows to interface with Nominatim, Google, TomTom, Mapbox, etc. for geocoding and reverse geocoding.
• osmdata (Padgham et al. 2017): Great for downloading spatial data from OpenStreetMap, via the Overpass API.
• arcgeocoder (Hernangómez 2024): Lite interface for geocoding with the ArcGIS REST API Service.

Usage

sf objects

With nominatimlite you can extract spatial objects easily:

library(nominatimlite)

# Extract some points - Pizza Hut in California

CA <- geo_lite_sf("California", points_only = FALSE)

pizzahut <- geo_lite_sf(
  "Pizza Hut, California",
  limit = 50,
  custom_query = list(countrycodes = "us")
)

library(ggplot2)

ggplot(CA) +
  geom_sf() +
  geom_sf(data = pizzahut, col = "red")

You can also extract polygon and line objects (if available) using the option points_only = FALSE:

sol_poly <- geo_lite_sf("Statue of Liberty, NY, USA", points_only = FALSE)

ggplot(sol_poly) +
  geom_sf()

Geocoding and reverse geocoding

Note: examples adapted from tidygeocoder package

In this first example we will geocode a few addresses using the geo_lite() function:

library(tibble)

# create a dataframe with addresses
some_addresses <- tribble(
  ~name, ~addr,
  "White House", "1600 Pennsylvania Ave NW, Washington, DC",
  "Transamerica Pyramid", "600 Montgomery St, San Francisco, CA 94111",
  "Willis Tower", "233 S Wacker Dr, Chicago, IL 60606"
)

# geocode the addresses
lat_longs <- geo_lite(
  some_addresses$addr,
  lat = "latitude",
  long = "longitude",
  progressbar = FALSE
)

Only latitude and longitude are returned from the geocoder service in this example, but full_results = TRUE can be used to return all of the data from the geocoder service.

To perform reverse geocoding (obtaining addresses from geographic coordinates), we can use the reverse_geo_lite() function. The arguments are similar to the geo_lite() function, but now we specify the input data columns with the lat and long arguments. The dataset used here is from the geocoder query above. The single line address is returned in a column named by the address.

reverse <- reverse_geo_lite(
  lat = lat_longs$latitude,
  long = lat_longs$longitude,
  address = "address_found",
  progressbar = FALSE
)

For more advanced users, see Nominatim docs to check the parameters available.

References