Visualize central vertices
As we saw in the last lesson, station 275 had the lowest out/in degree ratio. We can visualize this using make_ego_graph() to see all the outbound paths from this station. It's also useful to plot this on a geographic coordinate layout, not the default igraph layout. By default, igraph uses the layout_nicely() function to display your graph, making an algorithmic guess about what the best layout should be. However, in this case we want to specify the coordinates of each station, because when a vertex is above another it means it's actually north of it.
Este exercício faz parte do curso
Case Studies: Network Analysis in R
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
# Make an ego graph of the least traveled graph
g275 <- make_ego_graph(___, 1, nodes = "___", mode= "out")[[1]]
# Plot ego graph
plot(
g275,
# Weight the edges by weight attribute
edge.width = E(g275)$weight
)