Figure 2.7 Voronoi polygons associated with a set of point locations

figures

code

This is most conveniently made using spatstat, but I’ve shown it here making a point pattern into an sf dataset and then using sf::st_voronoi().

Code

library(spatstat)
library(sf)
library(ggplot2)

There are a few steps making a spatstat point pattern into a simple features dataset…

Code

pp <- rpoispp(100) |>
  as.data.frame() |>
  st_as_sf(coords = c("x", "y"), crs = 2193)

And there are a few more making a point dataset into a Voronoi polygon dataset.

Code

pp_vor <- pp |>
  st_union() |>
  st_voronoi() |>
  st_cast() |>
  st_as_sf(crs = st_crs(pp))

And finally a map.

Code

ggplot(pp_vor) +
  geom_sf(fill = "#dddddd", color = "white", lwd = 0.5) +
  geom_sf(data = pp, colour = "black", shape = 1, size = 2) +
  coord_sf(xlim = c(-0.05, 1.05), ylim = c(-0.05, 1.05), expand = FALSE) +
  theme_void()

Code

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