color.clusters {smerc}

Color clusters

Description

color.clusters is a helper function to color clusters of regions produced by an appropriate method, e.g., scan.test or uls.test. Regions that are not part of any cluster have no color.

Usage

color.clusters(
  x,
  idx = seq_along(x$clusters),
  col = grDevices::hcl.colors(length(idx))
)

Arguments

x

An object of class scan produced by a function such as scan.test.

idx

An index vector indicating the elements of object$clusters to print information for. The default is all clusters.

col

A vector of colors to color the clusters in x. Should have same length as the number of clusters in x.

Value

Returns a vector with colors for each region/centroid for the data set used to construct x.

Author(s)

Joshua French

Examples

set.seed(1)
data(nydf)
coords <- with(nydf, cbind(longitude, latitude))
out <- scan.test(
  coords = coords, cases = floor(nydf$cases),
  pop = nydf$pop, alpha = 0.2, longlat = TRUE,
  nsim = 9
)
#' # better plotting
if (require("sf", quietly = TRUE)) {
   data(nysf)
   plot(st_geometry(nysf), col = color.clusters(out))
   # plot only clusters 2 and 3
   plot(st_geometry(nysf),
        col = color.clusters(out, idx = c(2, 3)),
        border = "white")
}