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(tmap)

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

tm_shape(pp_vor, bbox = pp %>% st_union() %>% st_buffer(0.05)) + 
  tm_polygons(border.col = "white") +
  tm_shape(pp) + 
  tm_bubbles(col = "white", alpha = 0, border.col = "black", size = 0.1) +
  tm_layout(frame = FALSE)

Code

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