in src/lic/ppl/world/world.py [0:0]
def update_children_parents(self, node: RVIdentifier):
"""
Update the parents that the child no longer depends on.
:param node: the node whose parents are being evaluated.
"""
for child in self.diff_stack_.get_node_raise_error(node).children.copy():
if not self.variables_.contains_node(child):
continue
new_child_var = self.diff_stack_.get_node(child)
old_child_var = self.get_node_earlier_version(child)
if not new_child_var or not old_child_var:
continue
new_parents = new_child_var.parent
old_parents = old_child_var.parent if old_child_var is not None else set()
dropped_parents = old_parents - new_parents
for parent in dropped_parents:
# parent node variable may need to be added to the latest
# diff, so we may need to call get_node_in_world with
# to_create_new_diff = True.
parent_var = self.get_node_in_world(
parent, to_create_new_diff=not self.diff_.contains_node(parent)
)
# pyre-fixme
if not parent_var and child not in parent_var.children:
continue
parent_var.children.remove(child)
if len(parent_var.children) != 0 or parent in self.observations_:
continue
self.diff_stack_.mark_for_delete(parent)
self.diff_stack_.update_log_prob(
-1 * self.variables_.get_node_raise_error(parent).log_prob
)
# pyre-fixme[16]: `Optional` has no attribute `parent`.
ancestors = [(parent, x) for x in parent_var.parent]
while len(ancestors) > 0:
ancestor_child, ancestor = ancestors.pop(0)
# ancestor node variable may need to be added to the latest
# diff, so we may need to call get_node_in_world with
# to_create_new_diff = True.
ancestor_var = self.get_node_in_world(
ancestor,
to_create_new_diff=not self.diff_.contains_node(ancestor),
)
if ancestor_var is None:
continue
ancestor_var.children.remove(ancestor_child)
if (
len(ancestor_var.children) == 0
and ancestor not in self.observations_
):
self.diff_stack_.mark_for_delete(ancestor)
self.diff_stack_.update_log_prob(
-1 * self.variables_.get_node_raise_error(ancestor).log_prob
)
ancestors.extend([(ancestor, x) for x in ancestor_var.parent])