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Split a vector into groups

Source: R/split.R
vec_split.Rd

This is a generalisation of split() that can split by any type of vector, not just factors. Instead of returning the keys in the character names, the are returned in a separate parallel vector.

Usage

vec_split(x, by)

Arguments

x

Vector to divide into groups.

by

Vector whose unique values defines the groups.

Value

A data frame with two columns and size equal to vec_size(vec_unique(by)). The key column has the same type as by, and the val column is a list containing elements of type vec_ptype(x).

Note for complex types, the default data.frame print method will be suboptimal, and you will want to coerce into a tibble to better understand the output.

Dependencies

Examples

vec_split(mtcars$cyl, mtcars$vs)
#>   key                                                  val
#> 1   0 6, 6, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 4, 8, 6, 8
#> 2   1             4, 6, 6, 4, 4, 6, 6, 4, 4, 4, 4, 4, 4, 4
vec_split(mtcars$cyl, mtcars[c("vs", "am")])
#>   key.vs key.am                                val
#> 1      0      1                   6, 6, 4, 8, 6, 8
#> 2      1      1                4, 4, 4, 4, 4, 4, 4
#> 3      1      0                6, 6, 4, 4, 6, 6, 4
#> 4      0      0 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8

if (require("tibble")) {
  as_tibble(vec_split(mtcars$cyl, mtcars[c("vs", "am")]))
  as_tibble(vec_split(mtcars, mtcars[c("vs", "am")]))
}
#> # A tibble: 4 × 2
#>   key$vs   $am val           
#>    <dbl> <dbl> <list>        
#> 1      0     1 <df [6 × 11]> 
#> 2      1     1 <df [7 × 11]> 
#> 3      1     0 <df [7 × 11]> 
#> 4      0     0 <df [12 × 11]>