draw Sapporo city map using the tmap package

tmap_draw_sapporo.R

library(sf)
library(tmap)

# 参考にしたところ
# https://qiita.com/ocean_f/items/700aff67f3e35266b0fe

# 国土数値情報からデータをダウンロード
# https://nlftp.mlit.go.jp/ksj/gml/datalist/KsjTmplt-N03-v3_1.html
datafile <- file.path("data", "N03-20230101_01_GML",
                      "N03-23_01_230101.geojson")

hokkaido <- st_read(datafile) |>
  st_transform(crs = 6680)  # JGD2011平面直角座標系XII
sapporo_ku <- c("中央区", "北区", "東区", "白石区", "豊平区",
                "南区", "西区", "厚別区", "手稲区", "清田区")
sapporo <- hokkaido |>
  dplyr::filter(N03_003 == "札幌市") |>
  dplyr::mutate(`区` = factor(substring(N03_004, 4),
                              levels = sapporo_ku))
tm_shape(sapporo) +
  tm_polygons("区", legend.show = FALSE) +
  tm_text("区", size = 0.7)