Add numpy.array access to vector types of property maps

Now vector types of property maps can be accessed as arrays with the
get_array() and 'a' property, just like scalar property maps.

src/graph/graph_bind.cc

@@ -127,12 +127,24 @@ struct export_vector_types
         if (type_name == "long double")
             type_name = "long_double";
         string name = "Vector_" + type_name;
-        class_<vector<ValueType> >(name.c_str())
-            .def(vector_indexing_suite<vector<ValueType> >())
+        class_<vector<ValueType> > vc(name.c_str());
+        vc.def(vector_indexing_suite<vector<ValueType> >())
             .def("__eq__", &vector_equal_compare<ValueType>)
             .def("__ne__", &vector_nequal_compare<ValueType>);
+        wrap_array(vc, typename mpl::has_key<numpy_types,ValueType>::type());
         vector_from_list<ValueType>();
     }
+
+    template <class ValueType>
+    void wrap_array(class_<vector<ValueType> >& vc, mpl::true_) const
+    {
+        vc.def("get_array", &wrap_vector_not_owned<ValueType>);
+    }
+
+    template <class ValueType>
+    void wrap_array(class_<vector<ValueType> >& vc, mpl::false_) const
+    {
+    }
 };
 
 // exception translation

src/graph_tool/core.py

@@ -1099,3 +1099,16 @@ def init_edge_classes():
                     e.__class__.__iter__ = _edge_iter
 
 init_edge_classes()
+
+# Add convenience function to vector classes
+
+
+def _get_array_view(self):
+    return self.get_array()[:]
+
+vector_types = [Vector_bool, Vector_int32_t, Vector_int64_t, Vector_double,
+                Vector_long_double]
+for vt in vector_types:
+    vt.a = property(_get_array_view)
+Vector_string.a = None
+Vector_string.get_array = lambda self: None