Error with find_partition_multiplex

[elisabettabiondi]

Hi @vtraag,

I am dealing with a signed network and I would like to partition it into two clusters. I followed the example in the documentation:

import igraph as ig
import leidenalg as la
import numpy as np

g0 = ig.Graph.GRG(100, 0.2)
w = 10 * np.random.rand(len(g0.es)) * np.random.choice([-1,1],p=[0.1,0.9],size=len(g0.es))
g0.es['weight'] = w
g_pos = g0.subgraph_edges(g0.es.select(weight_gt=0), delete_vertices=False)
g_neg = g0.subgraph_edges(g0.es.select(weight_lt=0), delete_vertices=False)
g_neg.es['weight'] = [-w for w in g_neg.es['weight']]

part_pos = la.ModularityVertexPartition(g_pos, weights='weight')
part_neg = la.ModularityVertexPartition(g_neg, weights='weight')

partition = la.find_partition_multiplex([part_pos, part_neg], layer_weights=[1, -1],
                                        partition_type=la.ModularityVertexPartition)

This provided me with an error:

AttributeError: 'ModularityVertexPartition' object has no attribute 'vcount'

What error am I doing?

Thank you

[vtraag]

Hi @elisabettabiondi, you are calling find_partition_multiplex which is expecting to be passed igraph.Graphs, not leidenalg.VertexPartitions. If you look at the example in the documentation at https://leidenalg.readthedocs.io/en/stable/multiplex.html#negative-links, you can see that it uses optimise_partition_multiplex, not find_partition_multiplex.

This should solve your problem. If it doesn't, feel free to re-open the issue!