# articulation_points: Articulation points and bridges of a graph In igraph: Network Analysis and Visualization

 articulation_points R Documentation

## Articulation points and bridges of a graph

### Description

`articulation_points()` finds the articulation points (or cut vertices)

### Usage

``````articulation_points(graph)

bridges(graph)
``````

### Arguments

 `graph` The input graph. It is treated as an undirected graph, even if it is directed.

### Details

Articulation points or cut vertices are vertices whose removal increases the number of connected components in a graph. Similarly, bridges or cut-edges are edges whose removal increases the number of connected components in a graph. If the original graph was connected, then the removal of a single articulation point or a single bridge makes it undirected. If a graph contains no articulation points, then its vertex connectivity is at least two.

### Value

For `articulation_points()`, a numeric vector giving the vertex IDs of the articulation points of the input graph. For `bridges()`, a numeric vector giving the edge IDs of the bridges of the input graph.

### Author(s)

Gabor Csardi csardi.gabor@gmail.com

`biconnected_components()`, `components()`, `is_connected()`, `vertex_connectivity()`, `edge_connectivity()`

Connected components `biconnected_components()`, `component_distribution()`, `decompose()`

Connected components `biconnected_components()`, `component_distribution()`, `decompose()`

### Examples

``````
g <- disjoint_union(make_full_graph(5), make_full_graph(5))
clu <- components(g)\$membership
g <- add_edges(g, c(match(1, clu), match(2, clu)))
articulation_points(g)

g <- make_graph("krackhardt_kite")
bridges(g)

``````

igraph documentation built on Aug. 10, 2023, 9:08 a.m.