Summarizing by state
Another interesting column is land_area, which shows the land area in square miles. Here, you'll summarize both population and land area by state, with the purpose of finding the density (in people per square miles).
counties_selected <- counties %>%
select(state, county, population, land_area)
Latihan ini adalah bagian dari kursus
Data Manipulation with dplyr
Latihan interaktif praktis
Cobalah latihan ini dengan menyelesaikan kode contoh berikut.
counties_selected %>%
# Group by state
___
# Find the total area and population
___