mutated variable using case_when() -- am I using it efficiently?

[budugulo]

I have mutated adult using case_when(). Am I using case_when() efficiently?

df <- tibble(age = 16:21)
df %>% 
  mutate(adult = case_when(age >= 18 ~ TRUE,
                           age <  18 ~ FALSE)) 

age	adult
16	FALSE
17	FALSE
18	TRUE
19	TRUE
20	TRUE
21	TRUE

[nirgrahamuk]

That's fine.
Though in this example it's potentially overkill. Consider.

df %>% 
  mutate(adult = age>=18)

[Bugs]

The other issue is speed if you have to do more than a few. nirgrahamuk's answer takes 9.4 milliseconds while budugulo's answer takes 165.7 ms to run the code.

library(microbenchmark)
df <- tibble(age=sample(16:21, size=1000000, replace=T))
microbenchmark(
df %>%   mutate(adult = case_when(age >= 18 ~ TRUE, age <  18 ~ FALSE)),
df %>%   mutate(adult = age>=18),
times=50)