Conversion between vertex IDs and names

Vnames() is a faster alternative to Vattr() to get the "name" attribute, falling back to V() when it is not set. as_vids() and as_vnames() provide convenient shorthands using Vnames().

Usage

Vnames(graph)

as_vids(graph, vnames)

as_vnames(graph, vids)

Arguments

graph

An igraph_ptr object.

vnames

Vertex names stored in Vattr(g)$name.

vids

An integer vector of vertex IDs.

Value

Vnames() and as_vnames() return a vector of vertex names or IDs.

as_vids() returns an integer vector of vertex IDs.

Examples

g = graph_create(letters[1:6])
Vnames(g)
#> [1] "a" "b" "c" "d" "e" "f"
as_vids(g, c("d", "b"))
#> [1] 4 2
as_vnames(g, c(4L, 2L))
#> [1] "d" "b"

# Falls back to V(), not NULL
Vnames(graph_empty(3L))
#> [1] 1 2 3