Finds the snapped location of points on R5 network. Snapping is a very
important step of the routing process, which is when the origins and
destinations specified by the user are actually positioned on the network
created by R5. The snapping process in R5 is composed of two rounds.
First, it tries to snap the points within a radius of 300 meters from
themselves. If the first round is unsuccessful, then R5 expands the search
radius to 1.6 km. If yet again it is unsuccessful, then the unsnapped points
won't be used during the routing process. The snapped location of each point
depends on the transport mode set by the user, because some network edges
are not available to specific modes (e.g. a pedestrian-only street cannot be
used to snap car trips).
find_snap(r5r_core, points, mode = "WALK")An object to connect with the R5 routing engine, created with
setup_r5().
Either a POINT sf object with WGS84 CRS, or a data.frame
containing the columns id, lon and lat.
A string. Which mode to consider when trying to snap the points
to the network. Defaults to WALK, also allows BICYCLE and CAR.
A data.table with the original points, their respective
snapped coordinates on the street network and the Euclidean distance ( in
meters) between the original points and their snapped location. Points that
could not be snapped show NA coordinates and found = FALSE.
Other network functions:
street_network_to_sf(),
transit_network_to_sf()
library(r5r)
path <- system.file("extdata/poa", package = "r5r")
r5r_core <- setup_r5(data_path = path)
#> Using cached R5 version from /home/runner/work/_temp/Library/r5r/jar/r5-v6.9-all.jar
#>
#> Using cached network.dat from /home/runner/work/_temp/Library/r5r/extdata/poa/network.dat
points <- read.csv(file.path(path, "poa_hexgrid.csv"))
snap_df <- find_snap(r5r_core, points, mode = "WALK")
stop_r5(r5r_core)
#> r5r_core has been successfully stopped.