housing_dots.R

library(tmap)
library(tidycensus)
options(tigris_use_cache = TRUE)
sf::sf_use_s2(FALSE)

tarrant_housing <- get_acs(
  geography = "tract",
  state = "TX",
  county = "Tarrant",
  variables = c(
    `2014 or later` = "S2504_C01_009",
    `2010-2013` = "S2504_C01_010",
    `2000-2009` = "S2504_C01_011",
    `1980-1999` = "S2504_C01_012",
    `1960-1979` = "S2504_C01_013",
    `1940-1959` = "S2504_C01_014",
    `1939 or earlier` = "S2504_C01_015"
  ),
  year = 2020,
  geometry = TRUE
) 

tarrant_dots <- as_dot_density(
  tarrant_housing,
  value = "estimate",
  values_per_dot = 25,
  group = "variable",
  erase_water = TRUE,
  area_threshold = 0.95
)

tmap_mode("view")

tm_basemap(leaflet::providers$CartoDB.Positron) + 
  tm_shape(tarrant_dots) +
  tm_dots(col = "variable",
          border.lwd = 0,
          palette = "viridis",
          size = 0.01, 
          title = "1 dot = 25 housing units",
          id = NULL) +
  tm_view(dot.size.fixed = FALSE)