Add node_info.depth property

nxontology/ontology.py

@@ -371,6 +371,17 @@ def n_descendants(self) -> int:
  """Number of descendants of node in graph, including itself."""
  return len(self.descendants)
 
+ @property # type: ignore [misc]
+ @cache_on_frozen
+ def depth(self) -> int:
+ """Minimum shortest path distance from a root node to this node."""
+ depth = min(
+ nx.shortest_path_length(self.nxo.graph, root, self.node)
+ for root in self.ancestors & self.nxo.roots
+ )
+ assert isinstance(depth, int)
+ return depth
+
  @property # type: ignore [misc]
  @cache_on_frozen
  def intrinsic_ic(self) -> float:

nxontology/tests/ontology_test.py

@@ -72,6 +72,15 @@ def test_nxontology_leaves(metal_nxo_frozen: NXOntology) -> None:
  assert leaves == {"copper", "gold", "palladium", "platinum", "silver"}
 
 
+def test_node_info_root(metal_nxo_frozen: NXOntology) -> None:
+ """Test metal node_info. Metal is the only root node."""
+ info = metal_nxo_frozen.node_info("metal")
+ assert info.node == "metal"
+ assert info.n_descendants == metal_nxo_frozen.n_nodes
+ assert info.n_ancestors == 1
+ assert info.depth == 0
+
+
 def test_node_info_gold(metal_nxo_frozen: NXOntology) -> None:
  print(metal_nxo_frozen.graph.graph)
  gold_info = metal_nxo_frozen.node_info("gold")
@@ -81,6 +90,7 @@ def test_node_info_gold(metal_nxo_frozen: NXOntology) -> None:
  assert gold_info.url is None
  assert gold_info.n_descendants == 1
  assert gold_info.n_ancestors == 4
+ assert gold_info.depth == 2
 
 
 def test_set_graph_attributes(metal_nxo: NXOntology) -> None: