Vectorised Nested if-else Statements Similar to CASE WHEN in 'SQL'.

lest

Lest provides two functions for vectorised conditional recoding of variables. case_when() enables you to vectorise multiple if and else statements (like CASE WHEN in SQL). if_else() is a stricter and more predictable version of base::ifelse() that preserves attributes (and therefore works with Dates). The functions in lest are forks of the dplyr functions of the same name. For more infos please refer to the documentation.

Why use lest?

Use this package if you like the semantics of dplyr::case_when(), but do not want to use dplyr because of the dependencies it comes with. If you already use dplyr in your project, you gain no advantage from lest. lest::case_when() and lest::if_else() behave exactly identical to the dplyr equivalents, just that they do not support tidyeval syntax (like !!!).

Dependencies

lest depends only on base R, and will never add any external dependencies.

Installation

You can install lest from GitHub with:

# install.packages("devtools")
devtools::install_github("s-fleck/lest")

Example

x <- 1:50

case_when(
  x %% 35 == 0 ~ "fizz buzz",
  x %% 5 == 0 ~ "fizz",
  x %% 7 == 0 ~ "buzz",
  TRUE ~ as.character(x)
)

case_when(
  x %% 35 == 0 ~ 35,
  x %% 5 == 0 ~ 5,
  x %% 7 == 0 ~ 7,
  TRUE ~ NA
)