about summary refs log tree commit diff
diff options
context:
space:
mode:
-rw-r--r--gn3/computations/slink.py11
-rw-r--r--tests/unit/computations/test_slink.py3
2 files changed, 12 insertions, 2 deletions
diff --git a/gn3/computations/slink.py b/gn3/computations/slink.py
index 5288908..f3a6951 100644
--- a/gn3/computations/slink.py
+++ b/gn3/computations/slink.py
@@ -25,6 +25,16 @@ def raise_lengtherror_if_child_lists_are_not_same_as_parent(lists):
     if not all(map(len_is_same_as_parent, lists)):
         raise LengthError("All children lists should be same length as the parent.")
 
+def raise_valueerror_if_child_list_distance_from_itself_is_not_zero(lists):
+    def get_child_distance(child):
+        idx = lists.index(child)
+        return lists[idx][idx]
+    def distance_is_zero(dist):
+        return dist == 0
+    children_distances = map(get_child_distance, lists)
+    if not all(map(distance_is_zero, children_distances)):
+        raise ValueError("Distance of each child list/tuple from itself should be zero!")
+
 def nearest(lists, i, j):
     """Computes some form of distance.
 This is 'copied' over from genenetwork1, from https://github.com/genenetwork/genenetwork1/blob/master/web/webqtl/heatmap/slink.py#L42-L64.
@@ -35,5 +45,6 @@ This description should be updated once the form/type of 'distance' identified."
     raise_valueerror_if_data_is_not_lists_or_tuples(lists)
     raise_valueerror_if_lists_empty(lists)
     raise_lengtherror_if_child_lists_are_not_same_as_parent(lists)
+    raise_valueerror_if_child_list_distance_from_itself_is_not_zero(lists)
     #### END: Guard Functions ####
     return None
diff --git a/tests/unit/computations/test_slink.py b/tests/unit/computations/test_slink.py
index 816cd2f..1fb7bbb 100644
--- a/tests/unit/computations/test_slink.py
+++ b/tests/unit/computations/test_slink.py
@@ -35,8 +35,7 @@ class TestSlink(TestCase):
                 with self.assertRaises(LengthError):
                     nearest(lst, 1, 1)
 
-    def test_nearest_expects_exception_if_there_is_no_zero_at_childs_list_index_corresponding_to_its_index_in_parent(self):
-        # I don't like the name of this test. Make the name clearer
+    def test_nearest_expects_exception_if_distance_of_child_from_itself_is_not_zero(self):
         for lst in [[[1]],
                     [[1,2],[3,4]],
                     [1,0,0],[0,0,5],[0,3,4],