n_distinct {dplyr} | R Documentation |
n_distinct()
counts the number of unique/distinct combinations in a set
of one or more vectors. It's a faster and more concise equivalent to
nrow(unique(data.frame(...)))
.
n_distinct(..., na.rm = FALSE)
... |
Unnamed vectors. If multiple vectors are supplied, then they should have the same length. |
na.rm |
If |
A single number.
x <- c(1, 1, 2, 2, 2)
n_distinct(x)
y <- c(3, 3, NA, 3, 3)
n_distinct(y)
n_distinct(y, na.rm = TRUE)
# Pairs (1, 3), (2, 3), and (2, NA) are distinct
n_distinct(x, y)
# (2, NA) is dropped, leaving 2 distinct combinations
n_distinct(x, y, na.rm = TRUE)
# Also works with data frames
n_distinct(data.frame(x, y))