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.
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 offlow().- 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
zonescontaining the ids of the zone. By default this is the first column names in the zones.- origin_code
Name of the variable in
flowcontaining 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
flowcontaining 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
destinationscontaining 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).
See also
Other od:
dist_google(),
od2odf(),
od_aggregate_from(),
od_aggregate_to(),
od_coords2line(),
od_coords(),
od_dist(),
od_id,
od_oneway(),
od_to_odmatrix(),
odmatrix_to_od(),
points2flow(),
points2odf()
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)
#> Warning: ignoring all but the first attribute
l <- od2line(flow = od_data, zones = cents)
#> Warning: CRS object has comment, which is lost in output; in tests, see
#> https://cran.r-project.org/web/packages/sp/vignettes/CRS_warnings.html
# When destinations are different
head(destinations[1:5])
#> coordinates WZ11CD LAD11CD COWZEW_SG
#> 524 (-1.492713, 53.81042) E33012352 E08000035 3
#> 1936 (-1.53781, 53.80131) E33010351 E08000035 2
#> 2006 (-1.533468, 53.80576) E33012331 E08000035 5
#> 2712 (-1.540438, 53.81724) E33012280 E08000035 3
#> 2730 (-1.540901, 53.80167) E33010390 E08000035 7
#> 2799 (-1.521311, 53.81683) E33012310 E08000035 3
#> COWZEW_SGN COWZEW_G
#> 524 Metro suburbs 3d
#> 1936 Top jobs 2c
#> 2006 Manufacturing and distribution 5b
#> 2712 Metro suburbs 3a
#> 2730 Servants of society 7c
#> 2799 Metro suburbs 3d
od_data2 <- flow_dests[1:12, 1:3]
od_data2
#> Area.of.residence WZ11CD All
#> 920573 E02002361 E33010350 109
#> 920575 E02002361 E33010390 38
#> 920578 E02002361 E33010468 10
#> 920582 E02002361 E33012367 44
#> 920587 E02002361 E33012225 34
#> 920591 E02002361 E33012368 7
#> 920601 E02002361 E33012333 94
#> 921220 E02002363 E33012414 30
#> 921222 E02002363 E33012313 183
#> 921225 E02002363 E33010464 11
#> 921228 E02002363 E33012254 72
#> 921233 E02002363 E33012352 13
flowlines_dests <- od2line(od_data2, cents_sf, destinations = destinations_sf)
flowlines_dests
#> Simple feature collection with 12 features and 3 fields
#> Geometry type: LINESTRING
#> Dimension: XY
#> Bounding box: xmin: -1.563202 ymin: 53.79647 xmax: -1.492713 ymax: 53.83587
#> Geodetic CRS: WGS 84
#> First 10 features:
#> Area.of.residence WZ11CD All geometry
#> 1 E02002361 E33010350 109 LINESTRING (-1.516734 53.82...
#> 2 E02002361 E33010390 38 LINESTRING (-1.516734 53.82...
#> 3 E02002361 E33010468 10 LINESTRING (-1.516734 53.82...
#> 4 E02002361 E33012367 44 LINESTRING (-1.516734 53.82...
#> 5 E02002361 E33012225 34 LINESTRING (-1.516734 53.82...
#> 6 E02002361 E33012368 7 LINESTRING (-1.516734 53.82...
#> 7 E02002361 E33012333 94 LINESTRING (-1.516734 53.82...
#> 8 E02002363 E33012414 30 LINESTRING (-1.535617 53.82...
#> 9 E02002363 E33012313 183 LINESTRING (-1.535617 53.82...
#> 10 E02002363 E33010464 11 LINESTRING (-1.535617 53.82...
plot(flowlines_dests)
