st_weights {sfdep}

Calculate spatial weights

Description

Calculate polygon spatial weights from a nb list. See spdep::nb2listw() for further details.

Usage

st_weights(nb, style = "W", allow_zero = NULL, ...)

Arguments

nb

A neighbor list object as created by st_neighbors().

style

Default "W" for row standardized weights. This value can also be "B", "C", "U", "minmax", and "S". See spdep::nb2listw() for details.

allow_zero

If TRUE, assigns zero as lagged value to zone without neighbors.

...

additional arguments passed to spdep::nb2listw().

Details

Under the hood, st_weights() creates a listw object and then extracts the weights elements from it as the neighbours element is already–presumably–already existent in the neighbors list you've already created. listw objects are recreated using recreate_listw() when calculating other statistics.

Value

a list where each element is a numeric vector

See Also

Other weights: st_inverse_distance(), st_kernel_weights(), st_nb_dists()

Examples

if (requireNamespace("dplyr", quietly = TRUE)) {
library(magrittr)
guerry %>%
 dplyr::mutate(nb = st_contiguity(geometry),
               wt = st_weights(nb),
               .before = 1)

}
# using geometry column directly
nb <- st_contiguity(guerry$geometry)
wt <- st_weights(nb)
wt[1:3]