7. ceci constitue la fin du pipe

Source: vignettes/articles/mapview_07-pipe.Rmd 
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mapview can be used in piped expressions using %>%, most likely at the very end of it…

Here are just a few examples of piped workflows:

plotting feature unions

library(mapview)
library(leaflet)
library(dplyr)
library(sf)
# GitHub: hrbrmstr/albersusa
library(albersusa)

franconia %>%
  st_union %>%
  plot


mapviewing feature unions

franconia %>%
  st_union %>%
  mapview


union by district

franconia %>%
  group_by(district) %>%
  summarize %>%
  mapview(zcol = "district")


districts by area

franconia %>%
  group_by(district) %>%
  summarize %>%
  mutate(area = as.numeric(st_area(.) / 1e6)) %>%
  mapview(zcol = "area")


counties by area

franconia %>%
  mutate(area = as.numeric(st_area(.))) %>%
  mapview(zcol = "area", legend = TRUE)


breweries colored by district

breweries %>%
  st_intersection(franconia) %>%
  mapview(zcol = "district")


number of breweries by county

franconia %>%
  mutate(count = lengths(st_contains(., breweries))) %>%
  mapview(zcol = "count")


brewery density by county

franconia %>%
  mutate(count = lengths(st_contains(., breweries)),
         density = count / as.numeric(st_area(.))) %>%
  mapview(zcol = "density")


using native.crs for a USA composite map

albersusa::usa_composite("laea") %>%
  mapview(native.crs = TRUE, zcol = "pop_2014", legend = TRUE)