Estimate Regions Separated by Geographic Features

Divide an adjacency graph into regions by removing edges whose centerlines intersect a set of line features, such as roads or rivers.

regionalize(shp, lines, adj = adjacency(shp), epsg = 3857)

Arguments

shp

sf object to regionalize.

lines

sf line object representing separators.

adj

Optional zero-indexed adjacency graph. Defaults to adjacency(shp).

epsg

numeric EPSG code to planarize to. Default is 3857.

Value

integer vector of region labels with nrow(shp) entries

Examples

data(towns)
# make some weird roadlike feature passing through the towns
lines <- sf::st_sfc(sf::st_linestring(sf::st_coordinates(sf::st_centroid(towns))),
  crs = sf::st_crs(towns)
)
#> Warning: st_centroid assumes attributes are constant over geometries
regionalize(towns, lines)
#> [1] 1 2 1 1 2 2 2