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Query Node Descendants

Source: R/query_functions.R
query_descendants.Rd

Find descendant nodes for specified variables in a DAG.

Usage

query_descendants(.tdy_dag, .var = NULL)

Arguments

.tdy_dag

A tidy_dagitty or dagitty object

.var

Character vector of variables to query. If NULL, returns parents for all nodes.

Value

A tibble with columns:

  • node: The node

  • descendant_set: String representation of descendant nodes

  • descendants: List column containing descendant nodes

  • n_descendants: Number of descendants

Examples

library(ggdag)
dag <- dagify(
  y ~ x + z,
  x ~ w
)

query_descendants(dag)
#> # A tibble: 4 × 4
#>   node  descendant_set descendants n_descendants
#>   <chr> <chr>          <list>              <int>
#> 1 w     {x, y}         <chr [2]>               2
#> 2 x     {y}            <chr [1]>               1
#> 3 y     NA             <chr [1]>               0
#> 4 z     {y}            <chr [1]>               1
query_descendants(dag, .var = "w")
#> # A tibble: 1 × 4
#>   node  descendant_set descendants n_descendants
#>   <chr> <chr>          <list>              <int>
#> 1 w     {x, y}         <chr [2]>               2