build_adjacency_matrix: Build adjacency matrix

In njhenry/covidemr: Tools for Mapping COVID Excess Mortality

Description

Builds a matrix describing adjacency between polygons in the a spatial object. This function is a wrapper of two functions in the spdep package.

Usage

build_adjacency_matrix(
  poly_sp,
  style = "B",
  allow_zero_neighbors = TRUE,
  manually_add_links = list()
)

Arguments

poly_sp	A SpatialPolygonsDataFrame object
style	One of "B","W","C", or "S". For more information, see the documentation in the spdep package: https://www.rdocumentation.org/packages/spdep/versions/1.1-3/topics/nb2mat
allow_zero_neighbors	[bool, default TRUE] Allow polygons with no neighbors?
manually_add_links	[list, default NULL] A list of links to add in addition to those specified by polygon adjacency. This should be formatted as a list where each item is a numeric vector of length 2, specifying the indices of polygons that should be listed as adjacent. The numeric vectors are not sensitive to ordering (so item 'c(1, 3)' is the same as 'c(3, 1)')

Value

sparse dsCMatrix representing adjacency between polygons in the 'poly_sp' object

njhenry/covidemr documentation built on Feb. 2, 2022, 2:31 a.m.