Merge pull request #508 from GregDemand/master

Incorrect initialization in BallTreeBoruvka dual_tree_traversal

Author: lmcinnes

hdbscan/_hdbscan_boruvka.pyx

@@ -1283,7 +1283,8 @@ cdef class BallTreeBoruvkaAlgorithm (object):
         #       propagate the results up the tree.
         if node1_info.is_leaf and node2_info.is_leaf:
 
-            new_bound = 0.0
+            new_upper_bound = 0.0
+            new_lower_bound = DBL_MAX
 
             point_indices1 = self.idx_array[node1_info.idx_start:
                                             node1_info.idx_end]