dodgr (version 0.2.8)

weight_streetnet: weight_streetnet

Description

Weight (or re-weight) an sf or SC (silicate)-formatted OSM street network according to a named profile, selected from (foot, horse, wheelchair, bicycle, moped, motorcycle, motorcar, goods, hgv, psv).

Usage

weight_streetnet(
  x,
  wt_profile = "bicycle",
  wt_profile_file = NULL,
  turn_penalty = FALSE,
  type_col = "highway",
  id_col = "osm_id",
  keep_cols = NULL,
  left_side = FALSE
)
# S3 method for default
weight_streetnet(
  x,
  wt_profile = "bicycle",
  wt_profile_file = NULL,
  turn_penalty = FALSE,
  type_col = "highway",
  id_col = "osm_id",
  keep_cols = NULL,
  left_side = FALSE
)
# S3 method for sf
weight_streetnet(
  x,
  wt_profile = "bicycle",
  wt_profile_file = NULL,
  turn_penalty = FALSE,
  type_col = "highway",
  id_col = "osm_id",
  keep_cols = NULL,
  left_side = FALSE
)
# S3 method for sc
weight_streetnet(
  x,
  wt_profile = "bicycle",
  wt_profile_file = NULL,
  turn_penalty = FALSE,
  type_col = "highway",
  id_col = "osm_id",
  keep_cols = NULL,
  left_side = FALSE
)

Arguments

x

A street network represented either as sf LINESTRING objects, typically extracted with dodgr_streetnet, or as an SC (silicate) object typically extracted with the dodgr_streetnet_sc.

wt_profile

Name of weighting profile, or data.frame specifying custom values (see Details)

wt_profile_file

Name of locally-stored, .json-formatted version of dodgr::weighting_profiles, created with write_dodgr_wt_profile, and modified as desired.

turn_penalty

Including time penalty on edges for turning across oncoming traffic at intersections (see Note).

type_col

Specify column of the sf data.frame object which designates different types of highways to be used for weighting (default works with osmdata objects).

id_col

For sf-formatted data only: Specify column of the codesf data.frame object which provides unique identifiers for each highway (default works with osmdata objects).

keep_cols

Vectors of columns from x to be kept in the resultant dodgr network; vector can be either names or indices of desired columns.

left_side

Does traffic travel on the left side of the road (TRUE) or the right side (FALSE)? - only has effect on turn angle calculations for edge times.

Value

A data.frame of edges representing the street network, with distances in metres and times in seconds, along with a column of graph component numbers. Times for sf-formatted street networks are only approximate, and do not take into account traffic lights, turn angles, or elevation changes. Times for sc-formatted street networks take into account all of these factors, with elevation changes automatically taken into account for networks generated with the osmdata function osm_elevation().

See Also

write_dodgr_wt_profile, dodgr_times

Examples

# NOT RUN {
# hampi is included with package as an 'osmdata' sf-formatted street network
net <- weight_streetnet (hampi)
class(net) # data.frame
dim(net) # 6096  11; 6096 streets
# os_roads_bristol is also included as an sf data.frame, but in a different
# format requiring identification of columns and specification of custom
# weighting scheme.
colnm <- "formOfWay"
wts <- data.frame (name = "custom",
                   way = unique (os_roads_bristol [[colnm]]),
                   value = c (0.1, 0.2, 0.8, 1))
net <- weight_streetnet (os_roads_bristol, wt_profile = wts,
                         type_col = colnm, id_col = "identifier")
dim (net) # 406 11; 406 streets

# An example for a generic (non-OSM) highway, represented as the
# `routes_fast` object of the \pkg{stplanr} package, which is a
# SpatialLinesDataFrame.
# }
# NOT RUN {
library (stplanr)
# merge all of the 'routes_fast' lines into a single network
r <- overline (routes_fast, attrib = "length", buff_dist = 1)
r <- sf::st_as_sf (r, crs = 4326)
# We need to specify both a `type` and `id` column for the
# \link{weight_streetnet} function.
r$type <- 1
r$id <- seq (nrow (r))
graph <- weight_streetnet (r, type_col = "type", id_col = "id",
                           wt_profile = 1)
# }