Count the number of unique values

Returns the number of unique elements in x, optionally ignoring NAs.

Usage

n_unique(x, na.rm = FALSE)

Arguments

x

a vector

na.rm

logical; if TRUE, NAs are ignored when counting unique values

Value

An integer count of unique values.

Author

Ben Wiseman, benjamin.h.wiseman@gmail.com

Examples

n_unique(c(1, 2, 2, 3, NA))               # 4
#> [1] 4
n_unique(c(1, 2, 2, 3, NA), na.rm = TRUE) # 3
#> [1] 3