DiagrammeR (version 0.8.1)

add_edges: Add edges to an existing graph object

Description

With a graph object of class dgr_graph, add one or more edges of specified types to nodes within the graph.

Usage

add_edges(graph, edges_df = NULL, from = NULL, to = NULL, rel = NULL)

Arguments

graph

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

edges_df

an edge data frame that is created using create_edges.

from

a vector of the outgoing nodes from which each edge is connected.

to

a vector of the incoming nodes to which each edge is connected.

rel

a string specifying the relationship between the connected nodes.

Value

• a graph object of class dgr_graph.

Examples

# Create a graph with two nodes
graph <- create_graph(create_nodes(nodes = c("a", "b")))

# Add an edge between those nodes and attach a relationship to the edge
graph <- add_edges(graph, from = "a", to = "b",
                   rel = "to_get")

# Examples of pipeable graph building using 'create_edges' with
# 'add_edges' in order to include values for the 'style' edge attribute
# (it modifies the style of the connecting line)

library(magrittr)

graph <- create_graph() %>%
  add_node("a") %>%
  add_node("b") %>%
  add_edges(create_edges(from = "a", to = "b",
                         style = "solid")) %>%
  add_node("c") %>%
  add_node("d") %>%
  add_edges(create_edges(from = "c", to = "d",
                         style = "dashed")) %>%
  add_node("e") %>%
  add_node("f") %>%
  add_edges(create_edges(from = "e", to = "f",
                         style = "dotted")) %>%
  add_node("g") %>%
  add_node("h") %>%
  add_edges(create_edges(from = "g", to = "h",
                         style = "bold"))