Convert a data frame to a tree

Usage

nest_tree(data, id_col, parent_col, children_to)

Arguments

data: A data frame.
id_col: Id column. The values must be unique and non-missing.
parent_col: Parent column. Each value must either be missing (for the root elements) or appear in the id_col column.
children_to: Name of the column the children should be put.

Value

A tree like data frame.

Examples

df <- tibble::tibble(
  id = 1:5,
  x = letters[1:5],
  parent = c(NA, NA, 1L, 2L, 4L)
)
out <- nest_tree(df, id, parent, "children")
out
#> # A tibble: 2 × 3
#>      id x     children        
#>   <int> <chr> <list>          
#> 1     1 a     <tibble [1 × 3]>
#> 2     2 b     <tibble [1 × 3]>

out$children
#> [[1]]
#> # A tibble: 1 × 3
#>      id x     children
#>   <int> <chr> <list>  
#> 1     3 c     <NULL>  
#> 
#> [[2]]
#> # A tibble: 1 × 3
#>      id x     children        
#>   <int> <chr> <list>          
#> 1     4 d     <tibble [1 × 3]>
#> 
out$children[[2]]$children
#> [[1]]
#> # A tibble: 1 × 3
#>      id x     children
#>   <int> <chr> <list>  
#> 1     5 e     <NULL>  
#>