DiagrammeR (version 0.8.4)

add_edge_df: Add edges from an edge data frame to an existing graph object

Description

With a graph object of class dgr_graph add edges from an edge data frame to that graph.

Usage

add_edge_df(graph, edge_df)

Arguments

graph

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

edge_df

an edge data frame that is created using create_edges.

Value

a graph object of class dgr_graph.

Examples

# Create a graph with nodes and no edges
nodes <-
  create_nodes(
    nodes = c("a", "b", "c", "d"),
    type = "letter",
    color = c("red", "green", "grey", "blue"),
    value = c(3.5, 2.6, 9.4, 2.7))

graph <- create_graph(nodes_df = nodes)

# Create an edge data frame
edges <-
  create_edges(
    from = c("a", "b", "c"),
    to = c("d", "c", "a"),
    rel = "leading_to")

# Add the edge data frame to the graph object to create a
# graph with both nodes and edges
graph <-
  add_edge_df(
    graph = graph,
    edge_df = edges)

get_edges(graph, return_type = "vector")
#> [1] "a -> d" "b -> c" "c -> a"