Is it possible to exclude areas of maps made with sf and tmap?

Question

I have created a map of Europe using a shape file downloaded from Eurostat. The file also includes several European administered areas such as French Guiana. I would like to exclude these areas. Is that possible?

Here is a picture of the map, and here is my r code:

require(readxl)
library(sf)
library(tmap)
library(tmaptools)

options(scipen = 999)

data1 <- read_excel("National Data.1-kopi.xlsx")
mydata <- subset(data1, TIME == 2007)


mymap <- st_read("NUTS_RG_20M_2021_3035.shp", stringsAsFactors = FALSE)
str(mymap)

map_and_data <- inner_join(mymap, mydata)

tm_shape(map_and_data) +
  tm_polygons("POP25", id = "NUTS_ID", palette = "Blues")
  

Answer 1

I feel your pain, as I was facing exactly the same issue when preparing data for a blog post https://www.jla-data.net/eng/breadbaskets-of-europe/

At the end I resolved the issue in a hacky way - I filtered out problematic areas exceeding a certain distance from Bern (which makes a nice center for "civilized Europe" - I was happy to leave the bulk of Russia out, but needed the part around Königsberg in).

So consider this piece of code:

library(sf)
library(tmap)
library(dplyr)

# download shapefiles from GISCO API
europe <- giscoR::gisco_get_countries(resolution = "10",
                                      region = "Europe")


# Overseas France, Azores + Canaries, and don't get me started on East Prussia!
troublemakers <- subset(europe, CNTR_ID %in% c("FR", "PT", "ES", "RU"))

buffer <- tidygeocoder::geo("Bern", quiet = T) %>% 
  st_as_sf(coords = c("long", "lat"), crs = 4326) %>% 
  st_buffer(units::as_units(1750, "km")) %>% 
  st_geometry() # don't need the address column anymore

# remove the bits too far from Bern (roughly midway between Cadiz and Königsberg)
troublemakers <- troublemakers %>% 
  st_intersection(buffer) 

# administrative regions in equal area projection
europe <- europe %>% 
  filter(!CNTR_ID %in% c("RU", "SJ", "FR", "PT", "ES")) %>% 
  rbind(troublemakers) %>% 
  st_transform(3035) # equal area Lambert / "European Albers"

# apply it in a {tmap} fashion...
tm_shape(europe) +
  tm_polygons()