conversion between igraph and graphNEL graphs {igraph}R Documentation

Convert igraph graphs to graphNEL objects or back

Description

The graphNEL class is defined in the graph package, it is another way to represent graphs. These functions are provided to convert between the igraph and the graphNEL objects.

Usage

igraph.from.graphNEL(graphNEL, name = TRUE, weight = TRUE,
              unlist.attrs = TRUE)
igraph.to.graphNEL(graph)

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.

graph

An igraph graph object.

Details

igraph.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.

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.

igraph.to.graphNEL converts and igraph graph to a graphNEL graph. It converts all graph/vertex/edge attributes. If the igraph graph has a vertex attribute ‘name’, then it will be used to assign vertex names in the graphNEL graph. Otherwise igraph vertex ids will be used for this purpose.

Value

igraph.from.graphNEL returns an igraph graph object.

igraph.to.graphNEL returns a graphNEL graph object.

Author(s)

Gabor Csardi csardi@rmki.kfki.hu

See Also

get.adjacency, graph.adjacency, get.adjlist and graph.adjlist.

Examples

g <- graph.ring(10)
V(g)$name <- letters[1:10]
GNEL <- igraph.to.graphNEL(g)
g2 <- igraph.from.graphNEL(GNEL)
g2

[Package igraph version 0.5.5-4 Index]