A vertex is a neighbor of another one (in other words, the two vertices are adjacent), if they are incident to the same edge.
Usage
neighbors(graph, v, mode = c("out", "in", "all", "total"))Arguments
- graph
The input graph.
- v
The vertex of which the adjacent vertices are queried.
- mode
Whether to query outgoing (‘out’), incoming (‘in’) edges, or both types (‘all’). This is ignored for undirected graphs.
See also
Other structural queries:
[.igraph(),
[[.igraph(),
adjacent_vertices(),
are_adjacent(),
ends(),
get.edge.ids(),
gorder(),
gsize(),
head_of(),
incident(),
incident_edges(),
is_directed(),
tail_of()
Examples
g <- make_graph("Zachary")
n1 <- neighbors(g, 1)
n34 <- neighbors(g, 34)
intersection(n1, n34)
#> + 4/34 vertices, from 29e4ef2:
#> [1] 9 14 20 32