import stormpy import stormpy.core import stormpy.simulator import stormpy.shields import stormpy.examples import stormpy.examples.files """ Simulating a model with the usage of a post shield """ def example_post_shield_simulator(): path = stormpy.examples.files.prism_mdp_lava_simple formula_str = "Pmax=? [G !\"AgentIsInLavaAndNotDone\"]; Pmax=? [ F \"AgentIsInLavaAndNotDone\" ];" program = stormpy.parse_prism_program(path) formulas = stormpy.parse_properties_for_prism_program(formula_str, program) options = stormpy.BuilderOptions([p.raw_formula for p in formulas]) options.set_build_state_valuations(True) options.set_build_choice_labels(True) options.set_build_all_labels() model = stormpy.build_sparse_model_with_options(program, options) initial_state = model.initial_states[0] assert initial_state == 0 shield_specification = stormpy.logic.ShieldExpression(stormpy.logic.ShieldingType.POST_SAFETY, stormpy.logic.ShieldComparison.RELATIVE, 0.9) result = stormpy.model_checking(model, formulas[0], extract_scheduler=True, shield_expression=shield_specification) result2 = stormpy.model_checking(model, formulas[1], extract_scheduler=True) assert result.has_shield assert result2.has_scheduler shield = result.shield scheduler = result2.scheduler post_scheduler = shield.construct() simulator = stormpy.simulator.create_simulator(model, seed=42) while not simulator.is_done(): current_state = simulator.get_current_state() state_string = model.state_valuations.get_string(current_state) # print(F"Simulator is in state {state_string}.") sched_choice = scheduler.get_choice(current_state).get_deterministic_choice() # print(F"Scheduler choice {model.choice_labeling.get_labels_of_choice(model.get_choice_index(current_state, sched_choice))}") corrections = post_scheduler.get_choice(current_state).choice_map # print(corrections) correction_labels = [(model.get_label_of_choice(current_state, correction[0]), model.get_label_of_choice(current_state, correction[1])) for correction in corrections] # print(F"Correction Choices are {correction_labels}.") applied_correction = next((x[1] for x in corrections if x[0] == sched_choice), None) if applied_correction != None and applied_correction != sched_choice: print(F"Correction applied changed choice {sched_choice} to {applied_correction}") sched_choice = applied_correction observation, reward = simulator.step(sched_choice) if __name__ == '__main__': example_post_shield_simulator()