R: Head of the edge(s) in a graph

head_of {igraph} | R Documentation

## Head of the edge(s) in a graph

### Description

For undirected graphs, head and tail is not defined. In this case `head_of` returns vertices incident to the supplied edges, and `tail_of` returns the other end(s) of the edge(s).

### Usage

    head_of(graph, es)

### Arguments

`graph` | The input graph.
`es` | The edges to query.

### Value

A vertex sequence with the head(s) of the edge(s).

### See Also

Other structural queries: `[.igraph()`, `[[.igraph()`, `adjacent_vertices()`, `are_adjacent()`, `ends()`, `get.edge.ids()`, `gorder()`, `gsize()`, `incident_edges()`, `incident()`, `is_directed()`, `neighbors()`, `tail_of()`

[Package igraph version 1.2.10 Index]