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Themapsapi package provides an interface to the Google Maps APIs,currently four of them:

• GoogleMaps Direction API
• GoogleMaps Distance Matrix API
• GoogleMaps Geocode API
• MapsStatic API

Functionsmp_directions,mp_matrix andmp_geocode are used toaccess the Directions, Matrix and Geocode APIs, respectively. Theyreturn anxml_document object (packagexml2) with the responsecontents.

• Given adirections response, functionsmp_get_routes andmp_get_segments can be used to process the response document intoa spatial layer. Functionmp_get_routes gives each alternative asa separate line, while functionmp_get_segments gives each segment(that is, a portion of the route associated with specific drivinginstructions) as a separate line.

• Given adistance matrix response, functionmp_get_matrix can beused to obtain distance/duration matrices.

• Given ageocode response, functionsmp_get_points andmp_get_bounds can be used to obtain geocoded locations as a pointor polygon (bounds) layer.

The fourth functionmp_map is used to access the Maps Static API. Itreturns astars raster RGB image, which can be used as background inmaps.

The CRAN version can be installed with:

install.packages("mapsapi")

The development version can be installed usingremotes:

install.packages("remotes")remotes::install_github("michaeldorman/mapsapi")

Once installed, the package can be loaded withlibrary:

library(mapsapi)

Note: due tonew Google Maps APIpolicy,starting from June 2018 the functions require an API key.

key="AIz....."

The complete documentation can be found athttps://michaeldorman.github.io/mapsapi/.

The following code section obtains (and plots) the driving directionsfrom 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' layerr= mp_get_routes(doc)# Plotlibrary(maps)library(sf)#> Linking to GEOS 3.8.0, GDAL 3.0.4, PROJ 6.3.1map("state",fill=FALSE,col="grey")plot(st_geometry(r),col= c("red","green","blue"),add=TRUE)