case_when_factor: Turn case_when output into an ordered factor
In KoderKow/kowr: Utility Functions

Description Usage Arguments Value References Examples

Turn case_when output into an ordered factor

1	case_when_factor(...)

...

<dynamic-dots> A sequence of two-sided formulas. The left hand side (LHS) determines which values match this case. The right hand side (RHS) provides the replacement value.

The LHS must evaluate to a logical vector. The RHS does not need to be logical, but all RHSs must evaluate to the same type of vector.

Both LHS and RHS may have the same length of either 1 or n. The value of n must be consistent across all cases. The case of n == 0 is treated as a variant of n != 1.

NULL inputs are ignored.

An ordered factor vector of length 1 or n, matching the length of the logical input or output vectors, with the type (and attributes) of the first RHS. Inconsistent lengths or types will generate an error.

https://stackoverflow.com/questions/49572416/r-convert-to-factor-with-order-of-levels-same-with-case-when

library(dplyr)
mtcars2 <-
  mtcars %>%
  mutate(
    mpg_bin = case_when(
      mpg < 10 ~ "mpg < 10",
      mpg >= 10 & mpg < 20 ~ "10 <= mpg < 20",
      TRUE ~ "20 <= mpg"
    ),
    mpg_bin_factor = case_when_factor(
      mpg < 10 ~ "mpg < 10",
      mpg >= 10 & mpg < 20 ~ "10 <= mpg < 20",
      TRUE ~ "20 <= mpg"
    )
  ) %>%
  select(mpg, starts_with("mpg_bin")) %>%
  as_tibble()
mtcars2
class(mtcars2$mpg_bin)
class(mtcars2$mpg_bin_factor)
levels(mtcars2$mpg_bin_factor)