Fast Nesting

Quickly nest data tables (similar to dplyr::group_nest()).

dt_nest(dt_, ..., .key = "data")

Arguments

dt_

the data table to nest

...

the variables to group by

.key

the name of the list column; default is "data"

Value

A data.table with a list column containing data.tables

Examples

library(data.table)
dt <- data.table(
  x = rnorm(1e5),
  y = runif(1e5),
  grp = sample(1L:3L, 1e5, replace = TRUE)
)

dt_nest(dt, grp)
#> Key: <grp>
#>      grp                  data
#>    <int>                <list>
#> 1:     1 <data.table[33454x2]>
#> 2:     2 <data.table[33135x2]>
#> 3:     3 <data.table[33411x2]>