Data Visualization Snippets | World Map with Country Dots

ggplot2_map.R

library(tidyverse)
library(sf)

# Data --------------------------------------------------------------------

raw_survey <- read_csv(here::here("data", "input", "Survey", "Crisis+Data+Ecosystem+Survey_RAW.csv"))

# Wrangle -----------------------------------------------------------------

# remove the variable descriptions row, only useful for new colnames
raw_survey <- raw_survey |> slice(-1)

country_counts <- raw_survey |>
  rename(country = QID1319370883) |>
  count(country, sort = TRUE) |>
  drop_na()

# geocoding
country_counts <- country_counts |>
  mutate(
    iso3 = country |> countrycode::countrycode("country.name", destination = "iso3c")
  )

# Plot --------------------------------------------------------------------

# download shape file
world <- rnaturalearth::ne_countries(scale = "medium", returnclass = "sf")

# Drop Antarctica
world <- world |>
  filter(!continent %in% c("Antarctica"))

# Extract centroids for countries
# NOTE: ne_countries(scale = "small") will lead to errors with centroids
country_centroids <- world |>
  st_centroid() |>
  select(name, adm0_a3, geometry) |>
  mutate(
    lat = st_coordinates(geometry)[, 2],
    lon = st_coordinates(geometry)[, 1]
  )

# join counts to centroids
country_centroids <- country_centroids |>
  inner_join(country_counts, by = join_by("adm0_a3" == "iso3"))

# nrow(country_counts) == nrow(country_centroids)

world |>
  ggplot() +
  geom_sf(fill = "#F1B434", alpha = 0.3, color = "white") +
  geom_point(
    data = country_centroids, aes(x = lon, y = lat, size = n),
    fill = "#F1B434", color = "black", shape = 21, stroke = 0.1, show.legend = FALSE
  ) +
  theme_void() +
  ggview::canvas(width = 10, height = 6.3, units = "in", bg = "white", scale = 1, dpi = DPI)


# Export ------------------------------------------------------------------

DPI <- 600

ggsave(here::here("plots", "survey", "ecoystem_map.png"), width = 10, height = 6.3, units = "in", dpi = DPI, scale = 1, bg = "white")
ggsave(here::here("plots", "survey", "ecoystem_map.svg"), width = 10, height = 6.3, units = "in", dpi = DPI, scale = 1, bg = "white")