vec_unique: Find and count unique values In vctrs: Vector Helpers

Description

• `vec_unique()`: the unique values. Equivalent to `unique()`.

• `vec_unique_loc()`: the locations of the unique values.

• `vec_unique_count()`: the number of unique values.

Usage

 ```1 2 3 4 5``` ```vec_unique(x) vec_unique_loc(x) vec_unique_count(x) ```

Arguments

 `x` A vector (including a data frame).

Value

• `vec_unique()`: a vector the same type as `x` containing only unique values.

• `vec_unique_loc()`: an integer vector, giving locations of unique values.

• `vec_unique_count()`: an integer vector of length 1, giving the number of unique values.

Missing values

In most cases, missing values are not considered to be equal, i.e. `NA == NA` is not `TRUE`. This behaviour would be unappealing here, so these functions consider all `NAs` to be equal. (Similarly, all `NaN` are also considered to be equal.)

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15``` ```x <- rpois(100, 8) vec_unique(x) vec_unique_loc(x) vec_unique_count(x) # `vec_unique()` returns values in the order that encounters them # use sort = "location" to match to the result of `vec_count()` head(vec_unique(x)) head(vec_count(x, sort = "location")) # Normally missing values are not considered to be equal NA == NA # But they are for the purposes of considering uniqueness vec_unique(c(NA, NA, NA, NA, 1, 2, 1)) ```