Remove redundant parameter for group/ungroup_vector_property

src/graph_tool/centrality/__init__.py

@@ -528,7 +528,7 @@ def trust_transitivity(g, trust_map, source=None, target=None, vprop=None):
                                    _prop("e", g, trust_map),
                                    _prop("v", g, vprop))
     if target != -1 or source != -1:
-        vprop = ungroup_vector_property(g, vprop, [0])[0]
+        vprop = ungroup_vector_property(vprop, [0])[0]
     if target != -1 and source != -1:
         return vprop.a[target]
     return vprop

src/graph_tool/core.py

@@ -290,6 +290,7 @@ def group_vector_property(props, value_type=None, vprop=None, pos=None):
        A vector property map with the grouped values of each property map in
        ``props``.
     """
+    g = props[0].get_graph()
     vtypes = set()
     keys = set()
     for i, p in enumerate(props):
@@ -335,14 +336,12 @@ def group_vector_property(props, value_type=None, vprop=None, pos=None):
     return vprop
 
 
-def ungroup_vector_property(g, vprop, pos, props=None):
+def ungroup_vector_property(vprop, pos, props=None):
     """Ungroup vector property map ``vprop`` into a list of individual property
     maps.
 
     Parameters
     ----------
-    g : :class:`~graph_tool.Graph`
-        Graph to which the property map belong.
     vprop : :class:`~graph_tool.PropertyMap`
         Vector property map to be ungrouped.
     pos : list of ints (optional, default: None)
@@ -358,6 +357,7 @@ def ungroup_vector_property(g, vprop, pos, props=None):
        A list of property maps with the ungrouped values of ``vprop``.
     """
 
+    g = vprop.get_graph()
     _check_prop_vector(vprop, name="vprop", scalar=False)
     k = vprop.key_type()
     value_type = vprop.value_type().split("<")[1].split(">")[0]

src/graph_tool/draw/__init__.py

@@ -281,7 +281,7 @@ def graph_draw(g, pos=None, size=(15, 15), pin=False, layout= "neato",
     if pos != None:
         # copy user-supplied property
         if isinstance(pos, PropertyMap):
-            pos = ungroup_vector_property(g, pos, [0,1])
+            pos = ungroup_vector_property(pos, [0,1])
         else:
             pos = (g.copy_property(pos[0]), g.copy_property(pos[1]))
 
@@ -452,7 +452,7 @@ def graph_draw(g, pos=None, size=(15, 15), pin=False, layout= "neato",
     pos[0].a /= 100
     pos[1].a /= 100
 
-    pos = group_vector_property(g, pos)
+    pos = group_vector_property(pos)
 
     if return_bitmap:
         # This is a not-so-nice hack which obtains an image buffer from a png