add_islands_graph {DiagrammeR} | R Documentation

## Create a random islands graph with edges between the islands

### Description

To an existing graph object, add several Erdos-Renyi random graphs (the islands) using a common set of parameters, connected together by a fixed number of edges.

### Usage

    add_islands_graph(graph, n_islands, island_size, p, edges_between,
      type = NULL, label = TRUE, rel = NULL, node_aes = NULL,
      edge_aes = NULL, node_data = NULL, edge_data = NULL, set_seed = NULL)

### Arguments

`graph` | a graph object of class `dgr_graph`.
`n_islands` | the number of islands in the generated graph.
`island_size` | the size of the islands in the generated graph.
`p` | the probability of there being edges between the islands.
`edges_between` | The number of edges between islands.
`type` | an optional string that describes the entity type for all the nodes to be added.
`label` | 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 edges to be added.
`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.
`set_seed` | supplying a value sets a random seed of the `Mersenne-Twister` implementation.

### Examples

    # Create a graph of islands
    islands_graph <-
      create_graph() %>%
      add_islands_graph(
        n_islands = 4,
        island_size = 10,
        p = 0.5,
        edges_between = 1,
        set_seed = 23)

    # Get a count of nodes
    islands_graph %>%
      count_nodes()

    # Get a count of edges
    islands_graph %>%
      count_edges()

[Package DiagrammeR version 1.0.1 Index]