dplyr::case_when
似乎不像dplyr::mutate
调用中的其他命令.例如:
library(dplyr)
case_when(mtcars$carb <= 2 ~ "low",
mtcars$carb > 2 ~ "high") %>%
table
作品:
.
high low
15 17
但在mutate
链中放入case_when
:
mtcars %>%
mutate(cg = case_when(carb <= 2 ~ "low",
carb > 2 ~ "high"))
你会得到:
Error: object 'carb' not found
虽然这个很好用
mtcars %>%
mutate(cg = carb %>%
cut(c(0, 2, 8)))