Compute Spatial Weights for BLISA — computeSpatialWeights • blisa

Builds queen (nearby) and distance-decay (diffuse) spatial weight matrices from a bin-level sf object, excluding bins that have no neighbours.

Usage

computeSpatialWeights(bins, bin_size = 50, dmax = 250)

Arguments

bins: An sf object of spatial bins.
bin_size: Numeric. Bin spacing used to define queen adjacency (1.2 * bin_size radius).
dmax: Numeric. Maximum distance for diffuse-mode neighbours.

Value

A list with:

queen_wt: Spatial weights list for nearby (queen) mode.
dist_wt: Spatial weights list for diffuse (distance-decay) mode.
keep_idx_queen: Integer indices of bins used in queen-mode Moran.
keep_idx_dist: Integer indices of bins used in diffuse-mode Moran.
isolate_idx_queen: Integer indices of original queen-mode isolates.
isolate_idx_dist: Integer indices of original diffuse-mode isolates.
queen_nb_full: Full (unsubset) neighbour list for nearby mode, indexed over all bins.
dist_nb_full: Full (unsubset) neighbour list for diffuse mode, indexed over all bins.

Examples

if (FALSE) { # \dontrun{
set.seed(42)
pts  <- sf::st_as_sf(
  data.frame(x = runif(300, 0, 1000), y = runif(300, 0, 1000)),
  coords = c("x", "y"), crs = NA
)
bins <- sf::st_sf(
  geometry = sf::st_make_grid(pts, cellsize = 100,
                              what = "polygons", square = FALSE)
)
sw <- computeSpatialWeights(bins, bin_size = 100, dmax = 300)
names(sw)
} # }