Attributes can be set and retrieved in several ways:
with the
name
argument:Vattr(g, "name") = letters[1:6]
with the
$
operator:Vattr(g)$name = letters[1:6]
with the
[[
operator:Vattr(g)[["name"]] = letters[1:6]
direct operation with a data.frame:
Vattr(g) = data.frame(name = letters[1:6])
Using the name
argument for setting and $
operetor for getting is the most
efficient way according to the brief benchmarking.
Usage
Vattr(graph, name)
Vattr(graph, name) <- value
Eattr(graph, name)
Eattr(graph, name) <- value
V(graph)
E(graph)
Arguments
- graph
An
igraph_ptr
object.- name
Name of the attribute to query or set. If missing, all the attributes are returned or replaced.
- value
A vector or data.frame.
Value
Vattr()
and Eattr()
return a data.frame with the same nubmer of
rows as the number of vertices and edges in the graph, respectively.
V()
and E()
return an integer vector of vertex and edge IDs, respectively.
See also
Vnames()
for specialized function for "name" attribute.
Examples
g = graph_create(letters[1:6])
Vattr(g)
#> # A tibble: 6 × 1
#> name
#> <chr>
#> 1 a
#> 2 b
#> 3 c
#> 4 d
#> 5 e
#> 6 f
Eattr(g, "weight") = seq_len(ecount(g))
Eattr(g)
#> # A tibble: 3 × 1
#> weight
#> <int>
#> 1 1
#> 2 2
#> 3 3
V(g)
#> [1] 1 2 3 4 5 6
E(g)
#> [1] 1 2 3