Identify polygon neighbors — st_contiguity • sfdep

Given an sf geometry of type POLYGON or MULTIPOLYGON identify contiguity based neighbors.

Usage

st_contiguity(geometry, queen = TRUE, ...)

Arguments

geometry: an sf or sfc object.
queen: default TRUE. For more see ?spdep::poly2nb
...: additional arguments passed to spdep::poly2nb()

Value

a list of class nb

Details

Utilizes spdep::poly2nb()

See also

Other neighbors: st_dist_band(), st_knn()

Examples

# on basic polygons
geo <- sf::st_geometry(guerry)
st_contiguity(geo)
#> Neighbour list object:
#> Number of regions: 85 
#> Number of nonzero links: 420 
#> Percentage nonzero weights: 5.813149 
#> Average number of links: 4.941176 
if (requireNamespace("dplyr", quietyl = TRUE)) {
# in a pipe
library(magrittr)
guerry %>%
  dplyr::mutate(nb = st_contiguity(geometry), .before = 1)
 }