Compared to the base ifelse(), this function is more strict.
It checks that true and false are the same type. This
strictness makes the output type more predictable, and makes it somewhat
faster.
if_else(condition, true, false, missing = NULL)Logical vector
Values to use for TRUE and FALSE values of
condition. They must be either the same length as condition,
or length 1. They must also be the same type: if_else() checks that
they have the same type and same class. All other attributes are
taken from true.
If not NULL, will be used to replace missing
values.
Where condition is TRUE, the matching value from
true, where it's FALSE, the matching value from false,
otherwise NA.
x <- c(-5:5, NA)
if_else(x < 0, NA_integer_, x)
#> [1] NA NA NA NA NA 0 1 2 3 4 5 NA
if_else(x < 0, "negative", "positive", "missing")
#> [1] "negative" "negative" "negative" "negative" "negative" "positive"
#> [7] "positive" "positive" "positive" "positive" "positive" "missing"
# Unlike ifelse, if_else preserves types
x <- factor(sample(letters[1:5], 10, replace = TRUE))
ifelse(x %in% c("a", "b", "c"), x, factor(NA))
#> [1] NA 2 2 1 2 2 2 2 NA NA
if_else(x %in% c("a", "b", "c"), x, factor(NA))
#> [1] <NA> c c a c c c c <NA> <NA>
#> Levels: a c d e
# Attributes are taken from the `true` vector,