Dear all,
I am trying to plot a "sum of graphs" in R and in Python, using Igraph. I can do it correctly in R, but I am facing some problems to reproduce it in Python. I was wondering if you could help me with this.
Please consider the following toy code in R:
library(igraph)
nodes1 = c("a","b","c")
nodes2 = c("c","d","e")
edges1 = matrix( c("a", "b", "b", "c","c","a"), nc = 2, byrow = TRUE)
edges2 = matrix( c("c", "d", "d", "e","e","c"), nc = 2, byrow = TRUE)
g1 = graph(edges1,directed=FALSE)
g2 = graph(edges2,directed=FALSE)
plot(g1+g2);
you can see that in the plot(g1+g2) the vertex "c" is shared by both graphs. So actually I can plot one connected graph with the vertices "a","b","c","d","e".
I would like to reproduce it in Python. The best way I think now is the following code, but it is failing:
import igraph
nodes1 = ["a","b","c"]
nodes2 = ["c","d","e"]
edges1 = [["a","b"],["b","c"],["c","a"]]
edges2 = [["c","d"],["d","e"],["e","c"]]
g1 = igraph.Graph(directed=False)
g2 = igraph.Graph(directed=False)
g1.add_vertices(nodes1)
g2.add_vertices(nodes2)
g1.add_edges(edges1)
g2.add_edges(edges2)
igraph.plot(g1+g2);
you can see that the igraph.plot(g1+g2) does not consider that vertex "c" is shared by g1 and g2. Do you have any idea why these codes have different behaviour? I know I am building the graphs in different ways, but I was not able to build the graph in Python in the same way I do it in R.
Sorry if it is a silly question (I used to program in R during some years, but I am just a beginner in Python). Thanks for any help or advice!
Best,
Charles