# R igraph manual pages

Use this if you are using igraph from R

## Eccentricity of the vertices in a graph

### Description

The eccentricity of a vertex is its shortest path distance from the farthest other node in the graph.

### Usage

eccentricity(graph, vids = V(graph), mode = c("all", "out", "in", "total"))


### Arguments

 graph The input graph, it can be directed or undirected. vids The vertices for which the eccentricity is calculated. mode Character constant, gives whether the shortest paths to or from the given vertices should be calculated for directed graphs. If out then the shortest paths from the vertex, if in then to it will be considered. If all, the default, then the corresponding undirected graph will be used, edge directions will be ignored. This argument is ignored for undirected graphs.

### Details

The eccentricity of a vertex is calculated by measuring the shortest distance from (or to) the vertex, to (or from) all vertices in the graph, and taking the maximum.

This implementation ignores vertex pairs that are in different components. Isolate vertices have eccentricity zero.

### Value

eccentricity returns a numeric vector, containing the eccentricity score of each given vertex.

### References

radius for a related concept, distances for general shortest path calculations.
g <- make_star(10, mode="undirected")