Valhalla is a routing service that is based on OpenStreetMap data. This package provides an interface to the Valhalla API from R. It allows you to query the Valhalla API for routes, isochrones, time-distance matrices, nearest point on the road network, and elevation data.
This package relies on the usage of a running Valhalla server (tested with versions 3.4.x and 3.5.x of Valhalla).
vl_route(): Get route between locations.vl_matrix(): Get travel time matrices between points.vl_locate(): Get the nearest point on the road network.vl_elevation(): Get elevation data at given location(s).vl_isochrone(): Get isochrone polygons.vl_optimized_route(): Get optimized route between locations.vl_status(): Get information on Valhalla service.
- Stable version from CRAN:
install.packages("valh")- Development version from the r-universe.
install.packages("valh", repos = "https://riatelab.r-universe.dev")This is a short overview of the main features of valh. The dataset
used here is shipped with the package, it is a sample of 100 random
pharmacies in Berlin (© OpenStreetMap
contributors) stored in a
geopackage file.
It demonstrates the use of vl_matrix, vl_route and vl_elevation
functions.
library(valh)## Data: (c) OpenStreetMap contributors, ODbL 1.0 - http://www.openstreetmap.org/copyright
## Routing: Valhalla - valhalla.github.io/valhalla
library(sf)## Linking to GEOS 3.13.1, GDAL 3.10.3, PROJ 9.6.0; sf_use_s2() is TRUE
pharmacy <- st_read(system.file("gpkg/apotheke.gpkg", package = "valh"), quiet = TRUE)
pharmacy <- pharmacy[1:10, ]One of valhalla’s strengths is that it allows you to use dynamic costing options at query time. For example, we can compare the travel time between each pharmacy by bicycle:
- with the default bicycle parameters (type of bicycle “hybrid” with an average speed of 18 km/h and a propensity to use roads, alongside other vehicles, of 0.5 out of 1 - the default value),
- with the road bicycle parameters (type of bicycle “road” with an average speed of 25 km/h and a propensity to use roads, alongside other vehicles, of 1 out of 1).
These costing options for each costing model (‘auto’, ‘bicycle’, etc.) are documented in Valhalla’s documentation.
default_bike <- vl_matrix(loc = pharmacy, costing = "bicycle")
road_bike <- vl_matrix(loc = pharmacy, costing = "bicycle",
costing_options = list(bicycle_type = "Road", use_roads = "1"))The object returned by vl_matrix is a list with 4 elements:
sources: origin point coordinates,destinations: destination point coordinates,distances: distance matrix between sources and destinations,durations: travel time matrix between sources and destinations.
default_bike$durations[1:5, 1:5]## 1 2 3 4 5
## 1 0.0 45.7 77.0 36.5 18.0
## 2 48.9 0.0 98.4 30.8 43.5
## 3 76.4 96.3 0.0 62.3 61.7
## 4 33.2 29.7 61.7 0.0 20.4
## 5 18.6 43.6 62.8 23.8 0.0
road_bike$durations[1:5, 1:5]## 1 2 3 4 5
## 1 0.0 32.8 51.2 25.2 13.1
## 2 34.1 0.0 62.4 22.5 31.2
## 3 49.7 62.6 0.0 44.0 40.9
## 4 23.0 21.3 43.4 0.0 14.9
## 5 12.4 30.3 41.8 15.5 0.0
We can see not only that travel times are different (which is to be expected, given that we’ve changed the cyclist’s default speed), but also that the path taken are different (as a consequence of the change in preference for using roads rather than cycle paths).
default_bike$distances - road_bike$distances## 1 2 3 4 5 6 7 8 9 10
## 1 0.000 0.071 1.052 0.653 0.040 0.026 1.492 -0.003 -0.865 0.014
## 2 0.017 0.000 2.376 -0.513 -0.001 0.045 0.865 -0.001 1.114 0.494
## 3 1.176 2.107 0.000 0.074 0.759 0.405 0.069 0.750 0.812 1.172
## 4 0.238 -0.343 0.042 0.000 0.013 -0.155 1.309 0.097 -0.385 0.238
## 5 0.506 0.026 0.440 0.653 0.000 0.016 -0.872 0.000 -0.813 0.019
## 6 0.009 0.767 -0.414 -0.123 0.012 0.000 0.132 0.001 -0.072 0.010
## 7 0.013 0.111 0.016 0.053 0.047 0.040 0.000 0.054 -0.053 0.005
## 8 -0.053 0.035 0.486 0.001 0.018 0.005 0.787 0.000 -0.340 -0.057
## 9 -0.386 -0.173 0.557 -0.302 0.190 -0.794 -0.204 -0.221 0.000 -0.390
## 10 0.000 0.025 -1.127 0.724 0.089 0.028 1.489 -0.006 -0.868 0.000
We now calculate a route between two points, by foot, using the
vl_route function and calculate the elevation profile of the returned
route, using the vl_elevation function.
p1 <- pharmacy[3, ]
p2 <- pharmacy[6, ]
route <- vl_route(p1, p2, costing = "pedestrian")
plot(st_geometry(route), main = "Route between 2 pharmacies")
plot(c(st_geometry(p1), st_geometry(p2)), pch = 21, cex = 2, add = TRUE)
# We transform the LineString to Point geometries
pts_route <- sf::st_cast(st_geometry(route), "POINT")
elev <- vl_elevation(loc = pts_route, sampling_dist = 100)The object returned is an sf object with a point for each location where the altitude has been sampled and with the attributes ‘distance’ (the cumulative distance to the first point) and ‘height’ (the altitude).
We can use it to plot the elevation profile of the route.
plot(as.matrix(st_drop_geometry(elev)), type = "l", lwd = 2, ylim = c(20, 70), asp = 100,
main = "Elevation Profile")
We’ve included a vignette showing how to install your own instance of Valhalla, either locally or on a remote server, using Docker.
The package is designed to provide an easy-to-use interface to the
Valhalla routing service from R. Special care has been taken to support
multiple input formats, and the package treats sf objects as
first-class citizens in both input and output. Additionally, we have
tried to maintain a minimal number of dependencies.
This package offers an API that closely resembles that of the
osrm package which provides an R
interface to the OSRM routing service.
Note that there are other packages that provide an interface to Valhalla API from R :
- valhallr: This
package is on CRAN. It provides access to some of Valhalla’s services
(height, locate and optimized route are notably missing). It
depends on a number of rather heavy packages and it does not allow
sfobjects as input. - rvalhalla: This package
is not on CRAN. Although it can provide access to several Valhalla
services, it only makes it easy to use two of them (route and
sources_to_target). It does not accept
sfobjects as input.
One can contribute to the package through pull requests and report issues or ask questions here. See the CONTRIBUTING.md file for detailed instructions.