DiagrammeR (version 0.9.0)

create_subgraph_ws: Create a subgraph based on a selection of nodes or edges

Description

Create a subgraph based on a selection of nodes or edges stored in the graph object. Selections of nodes can be performed using the following select_... functions: select_nodes(), select_last_node(), select_nodes_by_degree(), select_nodes_by_id(), or select_nodes_in_neighborhood(). Alternatively, selections of edges can be made with these functions: select_edges(), select_last_edge(), or select_edges_by_node_id(). Selections of nodes or edges can also be performed using any of the traversal functions (trav_...).

Usage

create_subgraph_ws(graph)

Arguments

graph

a graph object of class dgr_graph that is created using create_graph.

Value

a graph object of class dgr_graph.

Examples

# NOT RUN {
# Create a node data frame (ndf)
ndf <-
  create_node_df(
    n = 6,
    value = c(3.5, 2.6, 9.4,
              2.7, 5.2, 2.1))

# Create an edge data frame (edf)
edf <-
  create_edge_df(
    from = c(1, 2, 4, 5, 2, 6),
    to = c(2, 4, 1, 3, 5, 5))

# Create a graph
graph <-
  create_graph(
    nodes_df = ndf,
    edges_df = edf)

# Create a selection of nodes, this selects
# nodes `1`, `3`, and `5`
graph <-
  graph %>%
  select_nodes("value > 3")

# Create a subgraph based on the selection
subgraph <- create_subgraph_ws(graph)

# Display the graph's node data frame
get_node_df(subgraph)
#>   id type label value
#> 1  1 <NA>  <NA>   3.5
#> 2  3 <NA>  <NA>   9.4
#> 3  5 <NA>  <NA>   5.2

# Display the graph's edge data frame
get_edge_df(subgraph)
#>   id from to  rel
#> 1  4    5  3 <NA>
# }