addNode {graph} | R Documentation

## addNode

### Description

Add one or more nodes to a graph.

### Usage

    addNode(node, object, edges)

### Arguments

`node` | A character vector of node names.
`object` | A `graph`
`edges` | A named list of edges.

### Details

The supplied `node`s are added to the set of nodes of the `object`.

If `edges` are provided then their must be the same number as there are `node`s and the must be in the same order. The elements of the `edges` list are vectors. They can be character vectors of node labels for nodes in `object` and if so then they are added with unit weights. If the vector is numeric then it must be named (with labels corresponding to nodes in the `object`) and the values are taken to be the edge weights.

When the `object` is a `distGraph` then the `edges` must be supplied and they must contain appropriate distances for all nodes both those in `object` and those supplied.

### Value

A new graph of the same class as `object` with the supplied node added to the set of nodes.

### Author(s)

R. Gentleman

### See Also

`removeNode`, `removeEdge`, `addEdge`

### Examples

      V <- LETTERS[1:4]
      edL1 <- vector("list", length=4)
      names(edL1) <- V
      for(i in 1:4)
         edL1[[i]] <- list(edges=c(2,1,4,3)[i], weights=sqrt(i))
      gR <- graphNEL(nodes=V, edgeL=edL1)
      gX <- addNode("X", gR)

    set.seed(123)
    g1 <- randomGraph(letters[1:10], 1:4, p=.3)
    g2 <- addNode("z", g1, edges=list(c("a", "h", "g")))

[Package graph version 1.72.0 Index]