igraph (version 1.3.5)

graph_from_graphnel: Convert graphNEL objects from the graph package to igraph

Description

The graphNEL class is defined in the graph package, it is another way to represent graphs. graph_from_graphnel takes a graphNEL graph and converts it to an igraph graph. It handles all graph/vertex/edge attributes. If the graphNEL graph has a vertex attribute called ‘name’ it will be used as igraph vertex attribute ‘name’ and the graphNEL vertex names will be ignored.

Usage

graph_from_graphnel(graphNEL, name = TRUE, weight = TRUE, unlist.attrs = TRUE)

Value

graph_from_graphnel returns an igraph graph object.

Arguments

graphNEL

The graphNEL graph.

name

Logical scalar, whether to add graphNEL vertex names as an igraph vertex attribute called ‘name’.

weight

Logical scalar, whether to add graphNEL edge weights as an igraph edge attribute called ‘weight’. (graphNEL graphs are always weighted.)

unlist.attrs

Logical scalar. graphNEL attribute query functions return the values of the attributes in R lists, if this argument is TRUE (the default) these will be converted to atomic vectors, whenever possible, before adding them to the igraph graph.

Details

Because graphNEL graphs poorly support multiple edges, the edge attributes of the multiple edges are lost: they are all replaced by the attributes of the first of the multiple edges.

See Also

as_graphnel for the other direction, as_adj, graph_from_adjacency_matrix, as_adj_list and graph.adjlist for other graph representations.

Examples

if (FALSE) {
## Undirected
g <- make_ring(10)
V(g)$name <- letters[1:10]
GNEL <- as_graphnel(g)
g2 <- graph_from_graphnel(GNEL)
g2

## Directed
g3 <- make_star(10, mode="in")
V(g3)$name <- letters[1:10]
GNEL2 <- as_graphnel(g3)
g4 <- graph_from_graphnel(GNEL2)
g4
}