Fix runtime error eigenvector() when no weights are used

This fixes ticket #84

src/graph/centrality/graph_eigenvector.cc

@@ -36,7 +36,7 @@ long double eigenvector(GraphInterface& g, boost::any w, boost::any c,
         throw ValueException("vertex property must be of floating point"
                              " value type");
 
-    typedef ConstantPropertyMap<int, GraphInterface::vertex_t> weight_map_t;
+    typedef ConstantPropertyMap<int, GraphInterface::edge_t> weight_map_t;
     typedef mpl::push_back<writable_edge_scalar_properties, weight_map_t>::type
         weight_props_t;
 
@@ -49,7 +49,7 @@ long double eigenvector(GraphInterface& g, boost::any w, boost::any c,
          (get_eigenvector(),
           _1, g.GetVertexIndex(), g.GetEdgeIndex(), _2,
           _3, epsilon, max_iter, ref(eig)),
-         writable_edge_scalar_properties(),
+         weight_props_t(),
          vertex_floating_properties())(w, c);
     return eig;
 }

src/graph/centrality/graph_eigenvector.hh

@@ -56,7 +56,7 @@ struct get_eigenvector
         }
 
         t_type norm = 0;
-        
+
 
         t_type delta = epsilon + 1;
         size_t iter = 0;
@@ -118,7 +118,7 @@ struct get_eigenvector
                 c[v] = c_temp[v];
             }
         }
-        
+
         eig = 1. / norm;
     }
 };

src/graph_tool/centrality/__init__.py

@@ -364,7 +364,7 @@ def eigenvector(g, weight=None, vprop=None, epsilon=1e-6, max_iter=None):
     ----------
     g : :class:`~graph_tool.Graph`
         Graph to be used.
-    weights : :class:`~graph_tool.PropertyMap` (optional, default: ``None``)
+    weight : :class:`~graph_tool.PropertyMap` (optional, default: ``None``)
         Edge property map with the edge weights.
     vprop : :class:`~graph_tool.PropertyMap`, optional (default: ``None``)
         Vertex property map where the values of eigenvector must be stored.