Changed max_edge in example/plot_rag.py

skimage/graph/rag.py

@@ -17,7 +17,7 @@ def min_weight(g, src, dst, n):
     src, dst : int
         The verices in `g` to be merged.
     n : int
-        A neighbor of `src` or `dst` or both
+        A neighbor of `src` or `dst` or both.
 
     Returns
     -------

skimage/graph/tests/test_rag.py

@@ -23,10 +23,14 @@ def test_rag_merge():
 
     gc = g.copy()
 
+    # We merge nodes and ensure that the minimum weight is chosen
+    # when there is a conflict.
     g.merge_nodes(0, 2)
     assert g.edge[1][2]['weight'] == 10
     assert g.edge[2][3]['weight'] == 30
 
+    # We specify `max_edge` as `weight_func` as ensure that maximum
+    # weight is chosen in case on conflict
     gc.merge_nodes(0, 2, weight_func=max_edge)
     assert gc.edge[1][2]['weight'] == 20
     assert gc.edge[2][3]['weight'] == 40