Use this if you are using igraph from R
This function is similar to incident, but it
queries multiple vertices at once.
incident_edges(graph, v, mode = c("out", "in", "all", "total"))
| graph | Input graph. | 
| v | The vertices to query | 
| mode | Whether to query outgoing (‘out’), incoming (‘in’) edges, or both types (‘all’). This is ignored for undirected graphs. | 
A list of edge sequences.
Other structural queries: 
[.igraph(),
[[.igraph(),
adjacent_vertices(),
are_adjacent(),
ends(),
get.edge.ids(),
gorder(),
gsize(),
head_of(),
incident(),
is_directed(),
neighbors(),
tail_of()
g <- make_graph("Zachary")
incident_edges(g, c(1, 34))