stplanr: od2line – R documentation

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od2line

Convert origin-destination data to spatial lines

Description

Origin-destination ('OD') flow data is often provided in the form of 1 line per flow with zone codes of origin and destination centroids. This can be tricky to plot and link-up with geographical data. This function makes the task easier.

Usage

od2line(
  flow,
  zones,
  destinations = NULL,
  zone_code = names(zones)[1],
  origin_code = names(flow)[1],
  dest_code = names(flow)[2],
  zone_code_d = NA,
  silent = FALSE
)

od2line2(flow, zones)

Arguments

`flow`	A data frame representing origin-destination data. The first two columns of this data frame should correspond to the first column of the data in the zones. Thus in `cents()`, the first column is geo_code. This corresponds to the first two columns of `flow()`.
`zones`	A spatial object representing origins (and destinations if no separate destinations object is provided) of travel.
`destinations`	A spatial object representing destinations of travel flows.
`zone_code`	Name of the variable in `zones` containing the ids of the zone. By default this is the first column names in the zones.
`origin_code`	Name of the variable in `flow` containing the ids of the zone of origin. By default this is the first column name in the flow input dataset.
`dest_code`	Name of the variable in `flow` containing the ids of the zone of destination. By default this is the second column name in the flow input dataset or the first column name in the destinations if that is set.
`zone_code_d`	Name of the variable in `destinations` containing the ids of the zone. By default this is the first column names in the destinations.
`silent`	TRUE by default, setting it to TRUE will show you the matching columns

Details

Origin-destination (OD) data is often provided in the form of 1 line per OD pair, with zone codes of the trip origin in the first column and the zone codes of the destination in the second column (see the vignette("stplanr-od")) for details. od2line() creates a spatial (linestring) object representing movement from the origin to the destination for each OD pair. It takes data frame containing origin and destination cones (flow) that match the first column in a a spatial (polygon or point) object (zones).

Examples

od_data <- stplanr::flow[1:20, ]
l <- od2line(flow = od_data, zones = cents_sf)
plot(sf::st_geometry(cents_sf))
plot(l, lwd = l$All / mean(l$All), add = TRUE)
l <- od2line(flow = od_data, zones = cents)
# When destinations are different
head(destinations[1:5])
od_data2 <- flow_dests[1:12, 1:3]
od_data2
flowlines_dests <- od2line(od_data2, cents_sf, destinations = destinations_sf)
flowlines_dests
plot(flowlines_dests)

stplanr

Sustainable Transport Planning

v0.8.2

MIT + file LICENSE

Authors

Robin Lovelace [aut, cre] (<https://orcid.org/0000-0001-5679-6536>), Richard Ellison [aut], Malcolm Morgan [aut] (<https://orcid.org/0000-0002-9488-9183>), Barry Rowlingson [ctb], Nick Bearman [ctb], Nikolai Berkoff [ctb], Scott Chamberlain [rev] (Scott reviewed the package for rOpenSci, see https://github.com/ropensci/onboarding/issues/10), Mark Padgham [ctb], Andrea Gilardi [ctb] (<https://orcid.org/0000-0002-9424-7439>)

Initial release