unnest {mlr3misc} | R Documentation

## Unnest List Data Table Columns

### Description

Transforms list columns to separate columns, possibly by reference. The original columns are removed from the returned table. All non-atomic objects in the list columns are expand to new list column.

### Usage

    unnest(x, cols, prefix = NULL)

### Arguments

`x` | (`data.table::data.table()`) `data.table::data.table()` with columns to unnest.
`cols` | (`character()`) Column names of list columns to operate on.
`prefix` | (`logical(1)` | `character(1)`) String to prefix the new column names with. Use `"{col}"` (without the quotes) as placeholder for the original column name.

### Value

(`data.table::data.table()`).

### Examples

    x = data.table::data.table(
      id = 1:2,
      value = list(list(a = 1, b = 2), list(a = 2, b = 2))
    )
    print(x)
    unnest(data.table::copy(x), "value")
    unnest(data.table::copy(x), "value", prefix = "{col}.")

[Package mlr3misc version 0.8.0 Index]