Node order missing

[aj2duncan]

…h no edges.

This is an updated version of #17

What my pull fixes (if applicable)

#15

What my pull improves (if applicable)

It allows nodes to have no connections. As these don't appear in the edges data frame they won't be created in tmp_graph.

Confirmation that you have tested your code

Example of test code below, although I have also used other graphs. There can be small rounding errors but I haven't had any mismatches down to 10^(-12).

library(sigmaNet)
library(igraph)

data = lesMis

sigmaObj = sigmaFromIgraph(data)

# code from addNodeSize()
edges <- jsonlite::fromJSON(sigmaObj$x$data)$edges
nodes <- jsonlite::fromJSON(sigmaObj$x$data)$nodes

tmp_graph <- igraph::graph_from_data_frame(d = edges,
                                                                           directed = FALSE,
                                                                           vertices = nodes$id)
nodes$size <- igraph::betweenness(tmp_graph)
table(abs(igraph::betweenness(data) - nodes$size) < 1e-12)