Re: [igraph] how to iterate a vertex seq to find neighbors

[Tamas Nepusz]

Hi Simone,

> I need to access the weight value of the link that connects mynode and
> myneighbor:
>
> for mynode in g.vs:

for mynode in g.vs:
  neighborhood = g.neighbors(mynode.index, type="OUT")
  for myneighbor in neighborhood:
    myExperience.append(g.vs[myneighbor]["weight"])

Note that you'll have to call g.neighbors() instead of  
igraph.GraphBase.neighbors() in the second line -- the former is  
necessary for Python to know which graph object you are working with.  
igraph.GraphBase.neighbors() is a so-called "unbound" method instance  
-- it is not bound to a specific graph object, therefore if you use  
igraph.GraphBase.neighbors(), the first argument must always be the  
graph object you want to bind the method to. (This is somewhat awkward  
in Python, that's why you should simply call g.neighbors() as it  
implicitly specifies the graph object you are working with).

Note also that g.vs behaves somewhat like a list: you can index it by  
integers and the result is always a Vertex object with the given  
index. That's why you can use g.vs[vertexindex]["weight"] to get the  
weight attribute of a specific vertex. Think of g.vs as a list of  
Vertex objects.

--
Tamas
>