lest
Vectorised Nested if-else Statements Similar to CASE WHEN in 'SQL'
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 ifelse() in 'base' that preserves attributes. These functions are forked from 'dplyr' with all package dependencies removed and behave identically to the originals.
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 preverves attributes (and therefore works with Dates). The
functions in lest are forks of the
dplyr functions of
the same name.
lest depends only on base, and will never add any external dependencies.
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 !!!).
Installation
You can install lest from GitHub with:
# install.packages("devtools")devtools::install_github("s-fleck/lest")
Example
x <- 1:50case_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)