[igraph] Adding tuples as vertex names

[Arjun Krishnan]

Hi

I'm trying to make a regular 2 dimensional lattice using igraph's python module. But I want to be able to refer to a vertex by its coordinates. So I do the following:

g = Graph()

g.add_vertex(name=(0,0))

g.add_vertex(name=(1,0))

g.add_edge((0,0),(1,0))

But this results in an error

---------------------------------------------------------------------------

TypeError                                 Traceback (most recent call last)

<ipython-input-52-b1b5147f3828> in <module>()

----> 1 g.add_edge((0,0),(1,0))

/usr/lib/python3.6/site-packages/igraph/__init__.py in add_edge(self, source, target, **kwds)

    235         """

    236         if not kwds:

--> 237             return self.add_edges([(source, target)])

    238 

    239         eid = self.ecount()

/usr/lib/python3.6/site-packages/igraph/__init__.py in add_edges(self, es)

    253           endpoints. Vertices are enumerated from zero.

    254         """

--> 255         return GraphBase.add_edges(self, es)

    256 

    257     def add_vertex(self, name=None, **kwds):

TypeError: only numbers, vertex names or igraph.Vertex objects can be converted to vertex IDs

Does this mean that vertex names can only be strings? Is there an easier way to make a lattice using

      g = Graph.Lattice([n,n])

And then refering to the vertices by their coordinates?

Arjun