add_star {DiagrammeR}R Documentation

Add a star of nodes to the graph

Description

With a graph object of class dgr_graph, add a node star to the graph.

Usage

add_star(graph, n, type = NULL, label = TRUE, rel = NULL,
  node_aes = NULL, edge_aes = NULL, node_data = NULL, edge_data = NULL)

Arguments

graph

a graph object of class dgr_graph.

n

the number of nodes comprising the star. The first node will be the center of the star.

type

an optional string that describes the entity type for the nodes to be added.

label

either a vector object of length n that provides optional labels for the new nodes, or, a boolean value where setting to TRUE ascribes node IDs to the label and FALSE yields a blank label.

rel

an optional string for providing a relationship label to all new edges created in the node star.

node_aes

an optional list of named vectors comprising node aesthetic attributes. The helper function node_aes() is strongly recommended for use here as it contains arguments for each of the accepted node aesthetic attributes (e.g., shape, style, color, fillcolor).

edge_aes

an optional list of named vectors comprising edge aesthetic attributes. The helper function edge_aes() is strongly recommended for use here as it contains arguments for each of the accepted edge aesthetic attributes (e.g., shape, style, penwidth, color).

node_data

an optional list of named vectors comprising node data attributes. The helper function node_data() is strongly recommended for use here as it helps bind data specifically to the created nodes.

edge_data

an optional list of named vectors comprising edge data attributes. The helper function edge_data() is strongly recommended for use here as it helps bind data specifically to the created edges.

Value

a graph object of class dgr_graph.

Examples

# Create a new graph and add 2
# stars of varying numbers of nodes
graph <-
  create_graph() %>%
  add_star(
    n = 4,
    type = "four_star") %>%
  add_star(
    n = 5,
    type = "five_star")

# Get node information from this graph
graph %>%
  get_node_info()

# Node and edge aesthetic and data
# attributes can be specified in
# the `node_aes`, `edge_aes`,
# `node_data`, and `edge_data`
# arguments

set.seed(23)

graph_w_attrs <-
  create_graph() %>%
  add_star(
    n = 4,
    label = c(
      "one", "two",
      "three", "four"),
    type = c(
      "a", "a", "b", "b"),
    rel = "A",
    node_aes = node_aes(
      fillcolor = "steelblue"),
    edge_aes = edge_aes(
      color = "red",
      penwidth = 1.2),
    node_data = node_data(
      value = c(
        1.6, 2.8, 3.4, 8.3)),
    edge_data = edge_data(
      value =
        rnorm(
          n = 3,
          mean = 5.0,
          sd = 1.0)))

# Get the graph's node data frame
graph_w_attrs %>%
  get_node_df()

# Get the graph's edge data frame
graph_w_attrs %>%
  get_edge_df()
[Package DiagrammeR version 1.0.1 Index]