The mapsapi
package provides an interface to the Google Maps APIs,
currently four of them:
Functions mp_directions
, mp_matrix
and mp_geocode
are used to
access the Directions, Matrix and Geocode APIs, respectively. They
return an xml_document
object (package xml2
) with the response
contents.
Given a directions response, functions mp_get_routes
and
mp_get_segments
can be used to process the response document into
a spatial layer. Function mp_get_routes
gives each alternative as
a separate line, while function mp_get_segments
gives each segment
(that is, a portion of the route associated with specific driving
instructions) as a separate line.
Given a distance matrix response, function mp_get_matrix
can be
used to obtain distance/duration matrices.
Given a geocode response, functions mp_get_points
and
mp_get_bounds
can be used to obtain geocoded locations as a point
or polygon (bounds) layer.
The fourth function mp_map
is used to access the Maps Static API. It
returns a stars
raster RGB image, which can be used as background in
maps.
The CRAN version can be installed with:
install.packages("mapsapi")
The development version can be installed using remotes
:
install.packages("remotes")
remotes::install_github("michaeldorman/mapsapi")
Once installed, the package can be loaded with library
:
library(mapsapi)
Note: due to new Google Maps API policy, starting from June 2018 the functions require an API key.
key = "AIz....."
The complete documentation can be found at https://michaeldorman.github.io/mapsapi/.
The following code section obtains (and plots) the driving directions from New-York to Los Angeles.
# Get routes (XML document)
doc = mp_directions(
origin = "New-York",
destination = "Los Angeles",
alternatives = TRUE,
key = key,
quiet = TRUE
)
# Extract lines 'sf' layer
r = mp_get_routes(doc)
# Plot
library(maps)
library(sf)
#> Linking to GEOS 3.8.0, GDAL 3.0.4, PROJ 6.3.1
map("state", fill = FALSE, col = "grey")
plot(st_geometry(r), col = c("red", "green", "blue"), add = TRUE)
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.