R: Convert graphNEL objects from the graph package to igraph

graph_from_graphnel {igraph} | R Documentation

## 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)

### 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.

### Value

`graph_from_graphnel` returns an igraph graph object.

### 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

    ## Not run:
    ## 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

    ## End(Not run)

[Package igraph version 1.2.6 Index]