def simplify_conditional_effects(real_state, opt_state, action_instance, axioms_from_name):
# TODO: compute required stream facts in a forward way and allow opt facts that are already known required
for effects in [action_instance.add_effects, action_instance.del_effects]:
for i, (conditions, effect) in reversed(list(enumerate(effects))):
if any(c.predicate in axioms_from_name for c in conditions):
raise NotImplementedError('Conditional effects cannot currently involve derived predicates')
if conditions_hold(real_state, conditions):
# Holds in real state
effects[i] = ([], effect)
elif not conditions_hold(opt_state, conditions):
# Does not hold in optimistic state
effects.pop(i)
else:
# TODO: handle more general case where can choose to achieve particular conditional effects
raise NotImplementedError('Conditional effects cannot currently involve certified predicates')
def recover_negative_axioms(real_task, opt_task, axiom_plans, action_plan,
negative_from_name):
action_plan = reinstantiate_action_instances(opt_task, action_plan)
simplify_conditional_effects(opt_task, action_plan, negative_from_name)
axiom_plans = list(map(reinstantiate_axiom_instances, axiom_plans))
axioms_from_name = get_derived_predicates(opt_task.axioms)
# TODO: could instead just accumulate difference between real and opt
opt_task.init = set(opt_task.init)
real_states = [set(real_task.init)]
preimage_plan = []
for axiom_plan, action_instance in safe_zip(axiom_plans, action_plan):
preimage = list(plan_preimage(axiom_plan + [action_instance], []))
assert conditions_hold(
opt_task.init,
(l for l in preimage if (l.predicate not in axioms_from_name and (
l.predicate not in negative_from_name))))
# TODO: only add derived facts and negative facts to fluent state to make normalizing easier
new_axiom_plan = extract_axiom_plan(opt_task,
preimage,
negative_from_name,
static_state=opt_task.init)
#static_state=real_states[-1])
assert new_axiom_plan is not None
preimage_plan.extend(new_axiom_plan + axiom_plan + [action_instance])
if action_instance.name != GOAL_NAME:
apply_action(opt_task.init, action_instance)
real_states.append(set(real_states[-1]))
apply_action(real_states[-1], action_instance)
return real_states, preimage_plan
def recover_negative_axioms(real_task, opt_task, axiom_plans, action_plan,
negative_from_name):
action_plan = reinstantiate_action_instances(opt_task, action_plan)
axiom_plans = list(map(reinstantiate_axiom_instances, axiom_plans))
axioms_from_name = get_derived_predicates(opt_task.axioms)
# TODO: could instead just accumulate difference between real and opt
opt_task.init = set(opt_task.init)
real_states = [set(real_task.init)]
preimage_plan = []
for axiom_plan, action_instance in safe_zip(axiom_plans, action_plan):
for literal in action_instance.precondition:
# TODO: check conditional effects
if literal.predicate in negative_from_name:
raise NotImplementedError(
'Negated predicates not currently supported within actions: {}'
.format(literal.predicate))
simplify_conditional_effects(real_states[-1], opt_task.init,
action_instance, axioms_from_name)
preimage = list(plan_preimage(axiom_plan + [action_instance], []))
assert conditions_hold(
opt_task.init,
(l for l in preimage if l.predicate not in axioms_from_name))
new_axiom_plan = extract_axiom_plan(opt_task,
preimage,
negative_from_name,
static_state=real_states[-1])
assert new_axiom_plan is not None
preimage_plan.extend(new_axiom_plan + axiom_plan + [action_instance])
if action_instance.name != GOAL_NAME:
apply_action(opt_task.init, action_instance)
real_states.append(set(real_states[-1]))
apply_action(real_states[-1], action_instance)
return real_states, preimage_plan
def extract_axiom_plan(task, action_instance, negative_from_name, static_state=set()):
import pddl_to_prolog
import build_model
import axiom_rules
import instantiate
axioms_from_name = get_derived_predicates(task.axioms)
derived_preconditions = {l for l in action_instance.precondition if l.predicate in axioms_from_name}
nonderived_preconditions = {l for l in action_instance.precondition if l not in derived_preconditions}
if not conditions_hold(task.init, nonderived_preconditions):
return None
axiom_from_action = get_necessary_axioms(action_instance, task.axioms, negative_from_name)
if not axiom_from_action:
return []
conditions_from_predicate = defaultdict(set)
for axiom, mapping in axiom_from_action.values():
for literal in get_literals(axiom.condition):
conditions_from_predicate[literal.predicate].add(literal.rename_variables(mapping))
original_init = task.init
original_actions = task.actions
original_axioms = task.axioms
task.init = {atom for atom in task.init if is_useful_atom(atom, conditions_from_predicate)}
# TODO: store map from predicate to atom
task.actions = axiom_from_action.keys()
task.axioms = []
# TODO: maybe it would just be better to drop the negative throughout this process until this end
with Verbose(False):
model = build_model.compute_model(pddl_to_prolog.translate(task)) # Changes based on init
task.actions = original_actions
task.axioms = original_axioms
opt_facts = instantiate.get_fluent_facts(task, model) | (task.init - static_state)
mock_fluent = MockSet(lambda item: (item.predicate in negative_from_name) or (item in opt_facts))
instantiated_axioms = instantiate_necessary_axioms(model, static_state, mock_fluent, axiom_from_action)
goal_list = []
with Verbose(False):
helpful_axioms, axiom_init, _ = axiom_rules.handle_axioms(
[action_instance], instantiated_axioms, goal_list)
axiom_init = set(axiom_init)
axiom_effects = {axiom.effect for axiom in helpful_axioms}
#assert len(axiom_effects) == len(axiom_init)
for pre in list(derived_preconditions) + list(axiom_effects):
if (pre not in axiom_init) and (pre.negate() not in axiom_init):
axiom_init.add(pre.positive().negate())
axiom_from_atom = get_achieving_axioms(task.init | axiom_init, helpful_axioms, negative_from_name)
axiom_plan = [] # Could always add all conditions
success = extract_axioms(axiom_from_atom, derived_preconditions, axiom_plan, negative_from_name)
task.init = original_init
#if not success:
# return None
return axiom_plan
def simplify_conditional_effects(opt_task,
action_instances,
negative_from_name={}):
# TODO: extract out the minimum set of conditional effects that are actually required
# TODO: handle more general case where can choose to achieve particular conditional effects
# will likely require planning with streams
axioms_from_name = get_derived_predicates(opt_task.axioms)
state = set(opt_task.init)
for action_instance in action_instances:
for effects in [
action_instance.add_effects, action_instance.del_effects
]:
for i, (conditions, effect) in reversed(list(enumerate(effects))):
if any(c.predicate in axioms_from_name for c in conditions):
raise NotImplementedError(
'Conditional effects cannot currently involve derived predicates'
)
neg_conditions = [
literal for literal in conditions
if literal.predicate in negative_from_name
]
pos_conditions = [
literal for literal in conditions
if literal not in neg_conditions
]
#if conditions_hold(real_state, opt_conditions):
if conditions_hold(state, pos_conditions):
# Holds in optimistic state
# Assuming that must achieve all possible conditional effects
if neg_conditions:
# TODO: use unsatisfiable
# Assuming that negative conditions should not be achieved
if len(neg_conditions) != 1:
raise NotImplementedError()
action_instance.precondition.extend(
l.negate() for l in neg_conditions)
effects.pop(i)
else:
action_instance.precondition.extend(pos_conditions)
effects[i] = ([], effect)
#elif not conditions_hold(opt_state, opt_conditions):
else:
# Does not hold in optimistic state
effects.pop(i)
apply_action(state, action_instance)
def recover_stream_plan(evaluations,
goal_expression,
domain,
stream_results,
action_plan,
negative,
unit_costs,
optimize=True):
import pddl_to_prolog
import build_model
import pddl
import axiom_rules
import instantiate
# Universally quantified conditions are converted into negative axioms
# Existentially quantified conditions are made additional preconditions
# Universally quantified effects are instantiated by doing the cartesian produce of types (slow)
# Added effects cancel out removed effects
opt_evaluations = evaluations_from_stream_plan(evaluations, stream_results)
opt_task = task_from_domain_problem(
domain,
get_problem(opt_evaluations, goal_expression, domain, unit_costs))
real_task = task_from_domain_problem(
domain, get_problem(evaluations, goal_expression, domain, unit_costs))
function_assignments = {
fact.fluent: fact.expression
for fact in opt_task.init # init_facts
if isinstance(fact, pddl.f_expression.FunctionAssignment)
}
type_to_objects = instantiate.get_objects_by_type(opt_task.objects,
opt_task.types)
results_from_head = get_results_from_head(opt_evaluations)
action_instances = []
for name, args in action_plan: # TODO: negative atoms in actions
candidates = []
for action in opt_task.actions:
if action.name != name:
continue
if len(action.parameters) != len(args):
raise NotImplementedError(
'Existential quantifiers are not currently '
'supported in preconditions: {}'.format(name))
variable_mapping = {
p.name: a
for p, a in zip(action.parameters, args)
}
instance = action.instantiate(variable_mapping, set(), MockSet(),
type_to_objects,
opt_task.use_min_cost_metric,
function_assignments)
assert (instance is not None)
candidates.append(((action, args), instance))
if not candidates:
raise RuntimeError(
'Could not find an applicable action {}'.format(name))
action_instances.append(candidates)
action_instances.append([(None, get_goal_instance(opt_task.goal))])
axioms_from_name = get_derived_predicates(opt_task.axioms)
negative_from_name = {n.name: n for n in negative}
opt_task.actions = []
opt_state = set(opt_task.init)
real_state = set(real_task.init)
preimage_plan = []
function_plan = set()
for layer in action_instances:
for pair, instance in layer:
nonderived_preconditions = [
l for l in instance.precondition
if l.predicate not in axioms_from_name
]
#nonderived_preconditions = instance.precondition
if not conditions_hold(opt_state, nonderived_preconditions):
continue
opt_task.init = opt_state
original_axioms = opt_task.axioms
axiom_from_action = get_necessary_axioms(instance, original_axioms,
negative_from_name)
opt_task.axioms = []
opt_task.actions = axiom_from_action.keys()
# TODO: maybe it would just be better to drop the negative throughout this process until this end
with Verbose(False):
model = build_model.compute_model(
pddl_to_prolog.translate(
opt_task)) # Changes based on init
opt_task.axioms = original_axioms
opt_facts = instantiate.get_fluent_facts(
opt_task, model) | (opt_state - real_state)
mock_fluent = MockSet(lambda item: (
item.predicate in negative_from_name) or (item in opt_facts))
instantiated_axioms = instantiate_necessary_axioms(
model, real_state, mock_fluent, axiom_from_action)
with Verbose(False):
helpful_axioms, axiom_init, _ = axiom_rules.handle_axioms(
[instance], instantiated_axioms, [])
axiom_from_atom = get_achieving_axioms(opt_state, helpful_axioms,
axiom_init,
negative_from_name)
axiom_plan = [] # Could always add all conditions
extract_axioms(axiom_from_atom, instance.precondition, axiom_plan)
# TODO: test if no derived solution
# TODO: compute required stream facts in a forward way and allow opt facts that are already known required
for effects in [instance.add_effects, instance.del_effects]:
for i, (conditions, effect) in enumerate(effects[::-1]):
if any(c.predicate in axioms_from_name
for c in conditions):
raise NotImplementedError(
'Conditional effects cannot currently involve derived predicates'
)
if conditions_hold(real_state, conditions):
# Holds in real state
effects[i] = ([], effect)
elif not conditions_hold(opt_state, conditions):
# Does not hold in optimistic state
effects.pop(i)
else:
# TODO: handle more general case where can choose to achieve particular conditional effects
raise NotImplementedError(
'Conditional effects cannot currently involve certified predicates'
)
#if any(conditions for conditions, _ in instance.add_effects + instance.del_effects):
# raise NotImplementedError('Conditional effects are not currently supported: {}'.format(instance.name))
# TODO: add axiom init to reset state?
apply_action(opt_state, instance)
apply_action(real_state, instance)
preimage_plan.extend(axiom_plan + [instance])
if not unit_costs and (pair is not None):
function_plan.update(
extract_function_results(results_from_head, *pair))
break
else:
raise RuntimeError('No action instances are applicable')
preimage = plan_preimage(preimage_plan, set())
preimage -= set(real_task.init)
negative_preimage = set(
filter(lambda a: a.predicate in negative_from_name, preimage))
preimage -= negative_preimage
# visualize_constraints(map(fact_from_fd, preimage))
# TODO: prune with rules
# TODO: linearization that takes into account satisfied goals at each level
# TODO: can optimize for all streams & axioms all at once
for literal in negative_preimage:
negative = negative_from_name[literal.predicate]
instance = negative.get_instance(map(obj_from_pddl, literal.args))
value = not literal.negated
if instance.enumerated:
assert (instance.value == value)
else:
function_plan.add(
PredicateResult(instance, value, opt_index=instance.opt_index))
node_from_atom = get_achieving_streams(evaluations, stream_results)
preimage_facts = list(
map(fact_from_fd, filter(lambda l: not l.negated, preimage)))
stream_plan = []
extract_stream_plan(node_from_atom, preimage_facts, stream_plan)
if not optimize: # TODO: detect this based on unique or not
return stream_plan + list(function_plan)
# TODO: search in space of partially ordered plans
# TODO: local optimization - remove one and see if feasible
reschedule_problem = get_problem(evaluations,
And(*preimage_facts),
domain,
unit_costs=True)
reschedule_task = task_from_domain_problem(domain, reschedule_problem)
reschedule_task.actions, stream_result_from_name = get_stream_actions(
stream_results)
new_plan, _ = solve_from_task(reschedule_task,
planner='max-astar',
debug=False)
# TODO: investigate admissible heuristics
if new_plan is None:
return stream_plan + list(function_plan)
new_stream_plan = [stream_result_from_name[name] for name, _ in new_plan]
return new_stream_plan + list(function_plan)
def recover_stream_plan(evaluations, current_plan, opt_evaluations,
goal_expression, domain, node_from_atom, action_plan,
axiom_plans, negative, replan_step):
# Universally quantified conditions are converted into negative axioms
# Existentially quantified conditions are made additional preconditions
# Universally quantified effects are instantiated by doing the cartesian produce of types (slow)
# Added effects cancel out removed effects
# TODO: node_from_atom is a subset of opt_evaluations (only missing functions)
real_task = task_from_domain_problem(
domain, get_problem(evaluations, goal_expression, domain))
opt_task = task_from_domain_problem(
domain, get_problem(opt_evaluations, goal_expression, domain))
negative_from_name = {
external.blocked_predicate: external
for external in negative if external.is_negated()
}
real_states, full_plan = recover_negative_axioms(real_task, opt_task,
axiom_plans, action_plan,
negative_from_name)
function_plan = compute_function_plan(opt_evaluations, action_plan)
full_preimage = plan_preimage(full_plan,
[]) # Does not contain the stream preimage!
negative_preimage = set(
filter(lambda a: a.predicate in negative_from_name, full_preimage))
negative_plan = convert_negative(negative_preimage, negative_from_name,
full_preimage, real_states)
function_plan.update(negative_plan)
# TODO: OrderedDict for these plans
# TODO: this assumes that actions do not negate preimage goals
positive_preimage = {
l
for l in (set(full_preimage) - real_states[0] - negative_preimage)
if not l.negated
}
steps_from_fact = {
fact_from_fd(l): full_preimage[l]
for l in positive_preimage
}
last_from_fact = {
fact: min(steps)
for fact, steps in steps_from_fact.items() if get_prefix(fact) != EQ
}
#stream_plan = reschedule_stream_plan(evaluations, target_facts, domain, stream_results)
# visualize_constraints(map(fact_from_fd, target_facts))
for result, step in function_plan.items():
for fact in result.get_domain():
last_from_fact[fact] = min(step, last_from_fact.get(fact, INF))
# TODO: get_steps_from_stream
stream_plan = []
last_from_stream = dict(function_plan)
for result in current_plan: # + negative_plan?
# TODO: actually compute when these are needed + dependencies
last_from_stream[result] = 0
if isinstance(result.external, Function) or (result.external
in negative):
if len(action_plan) != replan_step:
raise NotImplementedError(
) # TODO: deferring negated optimizers
# Prevents these results from being pruned
function_plan[result] = replan_step
else:
stream_plan.append(result)
curr_evaluations = evaluations_from_stream_plan(evaluations,
stream_plan,
max_effort=None)
extraction_facts = set(last_from_fact) - set(
map(fact_from_evaluation, curr_evaluations))
extract_stream_plan(node_from_atom, extraction_facts, stream_plan)
# Recomputing due to postprocess_stream_plan
stream_plan = postprocess_stream_plan(evaluations, domain, stream_plan,
last_from_fact)
node_from_atom = get_achieving_streams(evaluations,
stream_plan,
max_effort=None)
fact_sequence = [set(result.get_domain())
for result in stream_plan] + [extraction_facts]
for facts in reversed(fact_sequence): # Bellman ford
for fact in facts: # could flatten instead
result = node_from_atom[fact].result
if result is None:
continue
step = last_from_fact[fact] if result.is_deferrable() else 0
last_from_stream[result] = min(step,
last_from_stream.get(result, INF))
for domain_fact in result.instance.get_domain():
last_from_fact[domain_fact] = min(
last_from_stream[result],
last_from_fact.get(domain_fact, INF))
stream_plan.extend(function_plan)
# Useful to recover the correct DAG
partial_orders = set()
for child in stream_plan:
# TODO: account for fluent objects
for fact in child.get_domain():
parent = node_from_atom[fact].result
if parent is not None:
partial_orders.add((parent, child))
#stream_plan = topological_sort(stream_plan, partial_orders)
bound_objects = set()
for result in stream_plan:
if (last_from_stream[result]
== 0) or not result.is_deferrable(bound_objects=bound_objects):
for ancestor in get_ancestors(result, partial_orders) | {result}:
# TODO: this might change descendants of ancestor. Perform in a while loop.
last_from_stream[ancestor] = 0
if isinstance(ancestor, StreamResult):
bound_objects.update(out for out in ancestor.output_objects
if out.is_unique())
#local_plan = [] # TODO: not sure what this was for
#for fact, step in sorted(last_from_fact.items(), key=lambda pair: pair[1]): # Earliest to latest
# print(step, fact)
# extract_stream_plan(node_from_atom, [fact], local_plan, last_from_fact, last_from_stream)
# Each stream has an earliest evaluation time
# When computing the latest, use 0 if something isn't deferred
# Evaluate each stream as soon as possible
# Option to defer streams after a point in time?
# TODO: action costs for streams that encode uncertainty
state = set(real_task.init)
remaining_results = list(stream_plan)
first_from_stream = {}
#assert 1 <= replan_step # Plan could be empty
for step, instance in enumerate(action_plan):
for result in list(remaining_results):
# TODO: could do this more efficiently if need be
domain = result.get_domain() + get_fluent_domain(result)
if conditions_hold(state, map(fd_from_fact, domain)):
remaining_results.remove(result)
certified = {
fact
for fact in result.get_certified()
if get_prefix(fact) != EQ
}
state.update(map(fd_from_fact, certified))
if step != 0:
first_from_stream[result] = step
# TODO: assumes no fluent axiom domain conditions
apply_action(state, instance)
#assert not remaining_results # Not true if retrace
if first_from_stream:
replan_step = min(replan_step, *first_from_stream.values())
eager_plan = []
results_from_step = defaultdict(list)
for result in stream_plan:
earliest_step = first_from_stream.get(result, 0)
latest_step = last_from_stream.get(result, 0)
assert earliest_step <= latest_step
defer = replan_step <= latest_step
if not defer:
eager_plan.append(result)
# We only perform a deferred evaluation if it has all deferred dependencies
# TODO: make a flag that also allows dependencies to be deferred
future = (earliest_step != 0) or defer
if future:
future_step = latest_step if defer else earliest_step
results_from_step[future_step].append(result)
# TODO: some sort of obj side-effect bug that requires obj_from_pddl to be applied last (likely due to fluent streams)
eager_plan = convert_fluent_streams(eager_plan, real_states, action_plan,
steps_from_fact, node_from_atom)
combined_plan = []
for step, action in enumerate(action_plan):
combined_plan.extend(result.get_action()
for result in results_from_step[step])
combined_plan.append(
transform_action_args(pddl_from_instance(action), obj_from_pddl))
# TODO: the returned facts have the same side-effect bug as above
# TODO: annotate when each preimage fact is used
preimage_facts = {
fact_from_fd(l)
for l in full_preimage if (l.predicate != EQ) and not l.negated
}
for negative_result in negative_plan: # TODO: function_plan
preimage_facts.update(negative_result.get_certified())
for result in eager_plan:
preimage_facts.update(result.get_domain())
# Might not be able to regenerate facts involving the outputs of streams
preimage_facts.update(
result.get_certified()) # Some facts might not be in the preimage
# TODO: record streams and axioms
return eager_plan, OptPlan(combined_plan, preimage_facts)