如何使用statnet / igraph创建同时具有边缘和隔离的网络

Question

My question is similar to the one posted here: Network adding edges error

I am creating a network from scratches: I have data about 228 vertices, over a period of 13 years. In the first year, I have just 1781 edges: they do not involve all of my vertices (barely 164), therefore the remaining nodes should result as isolated.

I created the network starting from my edgelist, using the code

fdi.graph.2003 <- graph_from_data_frame(fdi.edge.2003, directed = T, vertices = fdi.attr.2003)

where fdi.edge.2003 is a data.frame containing edge attributes (including some potential weight columns): it only involves 164 vertices out of the total vertices defined by fdi.attr.2003 is a data.frame containing a row for each vertex that is involved in the edgelist (164 in total).

all i get is a network with 164 vertices and no isolates. However, I know they do exist in my data! Any suggestion on how to do it? I think that I shoul initialize a network with all 228 vertices, adding their attributes and then adding the edges. However, nothing I am trying is working: rather, I am receiving the most disparate errors related to "Illegal vertex reference in addEdges_R".

Any suggestion is more than welcome, also in the case it would involve the alternative package igraph, for which I am finding the same problem

Filippo

Answer 1

Use add.isolates from the sna package

net1 = as.network(cbind(1:3, 3:5)) #5 vertices, 3 edges
net2 = as.network(add.isolates(net1, 10), matrix.type = "edgelist") #15 v, 3 e

And then you'll probably want to create new vertex names, eg

net2%v%"vertex.names" = 1:15