R: Calculate the Bicomponents of a Graph

bicomponent.dist {sna} | R Documentation

## Calculate the Bicomponents of a Graph

### Description

`bicomponent.dist` returns the bicomponents of an input graph, along with size distribution and membership information.

### Usage

    bicomponent.dist(dat, symmetrize = c("strong", "weak"))

### Arguments

`dat` | a graph or graph stack.
`symmetrize` | symmetrization rule to apply when pre-processing the input (see `symmetrize`).

### Details

The bicomponents of undirected graph `G` are its maximal 2-connected vertex sets. `bicomponent.dist` calculates the bicomponents of G, after first coercing to undirected form using the symmetrization rule in `symmetrize`. In addition to bicomponent memberships, various summary statistics regarding the bicomponent distribution are returned; see below.

### Value

A list containing

`members` | A list, with one entry per bicomponent, containing component members.
`memberships` | A vector of component memberships, by vertex. (Note: memberships may not be unique.) Vertices not belonging to any bicomponent have membership values of `NA`.
`csize` | A vector of component sizes, by bicomponent.
`cdist` | A vector of length |V(G)| with the (unnormalized) empirical distribution function of bicomponent sizes.

### Note

Remember that bicomponents can intersect; when this occurs, the relevant vertices' entries in the membership vector are assigned to one of the overlapping bicomponents on an arbitrary basis. The `members` element of the return list is the safe way to recover membership information.

### Author(s)

Carter T. Butts buttsc@uci.edu

### References

Brandes, U. and Erlebach, T. (2005). Network Analysis: Methodological Foundations. Berlin: Springer.

### See Also

`component.dist`, `cutpoints`, `symmetrize`

### Examples

    #Draw a moderately sparse graph
    g<-rgraph(25,tp=2/24,mode="graph")

    #Compute the bicomponents
    bicomponent.dist(g)

[Package sna version 2.6 Index]