dplyr (version 0.1.1)

n_distinct: Efficiently count the number of unique values in a vector.

Description

This is a faster and more concise equivalent of length(unique(x))

Usage

n_distinct(x)

Arguments

x

a vector of values

Examples

x <- sample(1:10, 1e5, rep = TRUE)
length(unique(x))
n_distinct(x)