ͬͯΈΑ͏
select(starwars, name, gender, species)
filter(starwars, species == "Human", height <= 170)
mutate(starwars, BMI = mass / (height/100)^2)
arrange(starwars, gender, height)
summarise(starwars,
mean_mass = mean(mass, na.rm = TRUE),
mean_height = mean(height, na.rm = TRUE))
grouped <- group_by(starwars, species)
summarise(grouped,
mean_mass = mean(mass, na.rm = TRUE),
mean_height = mean(height, na.rm = TRUE),
count = n())
!33