예제 #1
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    def __init__(self, sess, brain, reward_buff_cap, trainer_parameters,
                 training, seed, run_id):
        """
        Responsible for collecting experiences and training PPO model.
        :param sess: Tensorflow session.
        :param  trainer_parameters: The parameters for the trainer (dictionary).
        :param training: Whether the trainer is set for training.
        """
        super(PPOTrainer, self).__init__(sess, brain.brain_name,
                                         trainer_parameters, training, run_id)

        self.param_keys = [
            'batch_size', 'beta', 'buffer_size', 'epsilon', 'gamma',
            'hidden_units', 'lambd', 'learning_rate', 'max_steps', 'normalize',
            'num_epoch', 'num_layers', 'time_horizon', 'sequence_length',
            'summary_freq', 'use_recurrent', 'graph_scope', 'summary_path',
            'memory_size', 'use_curiosity', 'curiosity_strength',
            'curiosity_enc_size'
        ]

        for k in self.param_keys:
            if k not in trainer_parameters:
                raise UnityTrainerException(
                    "The hyperparameter {0} could not be found for the PPO trainer of "
                    "brain {1}.".format(k, brain.brain_name))

        self.use_curiosity = bool(trainer_parameters['use_curiosity'])

        self.step = 0

        self.policy = PPOPolicy(seed, brain, trainer_parameters, sess,
                                self.is_training)

        stats = {
            'cumulative_reward': [],
            'episode_length': [],
            'value_estimate': [],
            'entropy': [],
            'value_loss': [],
            'policy_loss': [],
            'learning_rate': []
        }
        if self.use_curiosity:
            stats['forward_loss'] = []
            stats['inverse_loss'] = []
            stats['intrinsic_reward'] = []
            self.intrinsic_rewards = {}
        self.stats = stats

        self.training_buffer = Buffer()
        self.training_buffer2 = Buffer()

        self.cumulative_rewards = {}
        self._reward_buffer = deque(maxlen=reward_buff_cap)
        self.episode_steps = {}
        self.summary_path = trainer_parameters['summary_path']
        if not os.path.exists(self.summary_path):
            os.makedirs(self.summary_path)

        self.summary_writer = tf.summary.FileWriter(self.summary_path)
예제 #2
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def test_ppo_get_value_estimates(mock_communicator, mock_launcher,
                                 dummy_config):
    tf.reset_default_graph()
    mock_communicator.return_value = MockCommunicator(discrete_action=False,
                                                      visual_inputs=0)
    env = UnityEnvironment(" ")
    brain_infos = env.reset()
    brain_info = brain_infos[env.external_brain_names[0]]

    trainer_parameters = dummy_config
    model_path = env.external_brain_names[0]
    trainer_parameters["model_path"] = model_path
    trainer_parameters["keep_checkpoints"] = 3
    policy = PPOPolicy(0, env.brains[env.external_brain_names[0]],
                       trainer_parameters, False, False)
    run_out = policy.get_value_estimates(brain_info, 0, done=False)
    for key, val in run_out.items():
        assert type(key) is str
        assert type(val) is float

    run_out = policy.get_value_estimates(brain_info, 0, done=True)
    for key, val in run_out.items():
        assert type(key) is str
        assert val == 0.0

    # Check if we ignore terminal states properly
    policy.reward_signals["extrinsic"].use_terminal_states = False
    run_out = policy.get_value_estimates(brain_info, 0, done=True)
    for key, val in run_out.items():
        assert type(key) is str
        assert val != 0.0

    env.close()
    def __init__(self, brain, reward_buff_cap, trainer_parameters, training,
                 load, seed, run_id):
        """
        Responsible for collecting experiences and training PPO model.
        :param trainer_parameters: The parameters for the trainer (dictionary).
        :param reward_buff_cap: Max reward history to track in the reward buffer
        :param training: Whether the trainer is set for training.
        :param load: Whether the model should be loaded.
        :param seed: The seed the model will be initialized with
        :param run_id: The identifier of the current run
        """
        super().__init__(brain, trainer_parameters, training, run_id,
                         reward_buff_cap)
        self.param_keys = [
            "batch_size",
            "beta",
            "buffer_size",
            "epsilon",
            "hidden_units",
            "lambd",
            "learning_rate",
            "max_steps",
            "normalize",
            "num_epoch",
            "num_layers",
            "time_horizon",
            "sequence_length",
            "summary_freq",
            "use_recurrent",
            "summary_path",
            "memory_size",
            "model_path",
            "reward_signals",
        ]
        self.check_param_keys()

        # Make sure we have at least one reward_signal
        if not self.trainer_parameters["reward_signals"]:
            raise UnityTrainerException(
                "No reward signals were defined. At least one must be used with {}."
                .format(self.__class__.__name__))

        self.step = 0
        self.policy = PPOPolicy(seed, brain, trainer_parameters,
                                self.is_training, load)

        stats = defaultdict(list)
        # collected_rewards is a dictionary from name of reward signal to a dictionary of agent_id to cumulative reward
        # used for reporting only. We always want to report the environment reward to Tensorboard, regardless
        # of what reward signals are actually present.
        self.collected_rewards = {"environment": {}}
        for _reward_signal in self.policy.reward_signals.keys():
            self.collected_rewards[_reward_signal] = {}

        self.stats = stats

        self.training_buffer = Buffer()
        self.episode_steps = {}
예제 #4
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    def __init__(
        self,
        brain,
        reward_buff_cap,
        trainer_parameters,
        training,
        load,
        seed,
        run_id,
        multi_gpu,
    ):
        """
        Responsible for collecting experiences and training PPO model.
        :param trainer_parameters: The parameters for the trainer (dictionary).
        :param reward_buff_cap: Max reward history to track in the reward buffer
        :param training: Whether the trainer is set for training.
        :param load: Whether the model should be loaded.
        :param seed: The seed the model will be initialized with
        :param run_id: The identifier of the current run
        """
        super(PPOTrainer, self).__init__(brain, trainer_parameters, training,
                                         run_id, reward_buff_cap)
        self.param_keys = [
            "batch_size",
            "beta",
            "buffer_size",
            "epsilon",
            "hidden_units",
            "lambd",
            "learning_rate",
            "max_steps",
            "normalize",
            "num_epoch",
            "num_layers",
            "time_horizon",
            "sequence_length",
            "summary_freq",
            "use_recurrent",
            "summary_path",
            "memory_size",
            "model_path",
            "reward_signals",
        ]
        self.check_param_keys()

        if multi_gpu and len(get_devices()) > 1:
            self.ppo_policy = MultiGpuPPOPolicy(seed, brain,
                                                trainer_parameters,
                                                self.is_training, load)
        else:
            self.ppo_policy = PPOPolicy(seed, brain, trainer_parameters,
                                        self.is_training, load)
        self.policy = self.ppo_policy

        for _reward_signal in self.policy.reward_signals.keys():
            self.collected_rewards[_reward_signal] = {}
예제 #5
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    def __init__(self, brain, reward_buff_cap, trainer_parameters, training,
                 load, seed, run_id):
        """
        Responsible for collecting experiences and training PPO model.
        :param trainer_parameters: The parameters for the trainer (dictionary).
        :param training: Whether the trainer is set for training.
        :param load: Whether the model should be loaded.
        :param seed: The seed the model will be initialized with
        :param run_id: The The identifier of the current run
        """
        super(PPOTrainer, self).__init__(brain, trainer_parameters, training,
                                         run_id)
        self.param_keys = [
            'batch_size', 'beta', 'buffer_size', 'epsilon', 'gamma',
            'hidden_units', 'lambd', 'learning_rate', 'max_steps', 'normalize',
            'num_epoch', 'num_layers', 'time_horizon', 'sequence_length',
            'summary_freq', 'use_recurrent', 'summary_path', 'memory_size',
            'use_curiosity', 'curiosity_strength', 'curiosity_enc_size',
            'model_path'
        ]

        self.check_param_keys()
        self.use_curiosity = bool(trainer_parameters['use_curiosity'])
        self.step = 0
        self.policy = PPOPolicy(seed, brain, trainer_parameters,
                                self.is_training, load)

        stats = {
            'Environment/Cumulative Reward': [],
            'Environment/Episode Length': [],
            'Policy/Value Estimate': [],
            'Policy/Entropy': [],
            'Losses/Value Loss': [],
            'Losses/Policy Loss': [],
            'Policy/Learning Rate': []
        }
        if self.use_curiosity:
            stats['Losses/Forward Loss'] = []
            stats['Losses/Inverse Loss'] = []
            stats['Policy/Curiosity Reward'] = []
            self.intrinsic_rewards = {}
        self.stats = stats

        self.training_buffer = Buffer()
        self.cumulative_rewards = {}
        self._reward_buffer = deque(maxlen=reward_buff_cap)
        self.episode_steps = {}
        self.summary_path = trainer_parameters['summary_path']
        if not os.path.exists(self.summary_path):
            os.makedirs(self.summary_path)

        self.summary_writer = tf.summary.FileWriter(self.summary_path)
예제 #6
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    def create_policy(self, brain_parameters: BrainParameters) -> TFPolicy:
        """
        Creates a PPO policy to trainers list of policies.
        :param brain_parameters: specifications for policy construction
        :return policy
        """

        if self.multi_gpu and len(get_devices()) > 1:
            policy: PPOPolicy = MultiGpuPPOPolicy(
                self.seed,
                brain_parameters,
                self.trainer_parameters,
                self.is_training,
                self.load,
            )
        else:
            policy = PPOPolicy(
                self.seed,
                brain_parameters,
                self.trainer_parameters,
                self.is_training,
                self.load,
            )

        for _reward_signal in policy.reward_signals.keys():
            self.collected_rewards[_reward_signal] = defaultdict(lambda: 0)

        return policy
예제 #7
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def test_ppo_policy_evaluate(mock_communicator, mock_launcher, dummy_config):
    tf.reset_default_graph()
    mock_communicator.return_value = MockCommunicator(discrete_action=False,
                                                      visual_inputs=0)
    env = UnityEnvironment(" ")
    brain_infos = env.reset()
    brain_info = brain_infos[env.external_brain_names[0]]

    trainer_parameters = dummy_config
    model_path = env.external_brain_names[0]
    trainer_parameters["model_path"] = model_path
    trainer_parameters["keep_checkpoints"] = 3
    policy = PPOPolicy(0, env.brains[env.external_brain_names[0]],
                       trainer_parameters, False, False)
    run_out = policy.evaluate(brain_info)
    assert run_out["action"].shape == (3, 2)
    env.close()
예제 #8
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def test_ppo_policy_evaluate(mock_communicator, mock_launcher):
    tf.reset_default_graph()
    with tf.Session() as sess:
        mock_communicator.return_value = MockCommunicator(
            discrete_action=False, visual_inputs=0)
        env = UnityEnvironment(' ')
        brain_infos = env.reset()
        brain_info = brain_infos[env.brain_names[0]]

        trainer_parameters = dummy_config()
        graph_scope = env.brain_names[0]
        trainer_parameters['graph_scope'] = graph_scope
        policy = PPOPolicy(0, env.brains[env.brain_names[0]],
                           trainer_parameters, sess, False)
        init = tf.global_variables_initializer()
        sess.run(init)
        run_out = policy.evaluate(brain_info)
        assert run_out['action'].shape == (3, 2)
        env.close()
예제 #9
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def test_ppo_policy_evaluate(mock_communicator, mock_launcher, dummy_config):
    tf.reset_default_graph()
    mock_communicator.return_value = MockCommunicator(discrete_action=False,
                                                      visual_inputs=0)
    env = UnityEnvironment(" ")
    env.reset()
    brain_name = env.get_agent_groups()[0]
    batched_step = env.get_step_result(brain_name)
    brain_params = group_spec_to_brain_parameters(
        brain_name, env.get_agent_group_spec(brain_name))

    trainer_parameters = dummy_config
    model_path = brain_name
    trainer_parameters["model_path"] = model_path
    trainer_parameters["keep_checkpoints"] = 3
    policy = PPOPolicy(0, brain_params, trainer_parameters, False, False)
    run_out = policy.evaluate(batched_step, list(batched_step.agent_id))
    assert run_out["action"].shape == (3, 2)
    env.close()
예제 #10
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def create_policy_with_bc_mock(mock_brain, trainer_config, use_rnn, demo_file):
    # model_path = env.external_brain_names[0]
    trainer_config["model_path"] = "testpath"
    trainer_config["keep_checkpoints"] = 3
    trainer_config["use_recurrent"] = use_rnn
    trainer_config["behavioral_cloning"]["demo_path"] = (
        os.path.dirname(os.path.abspath(__file__)) + "/" + demo_file)

    policy = (PPOPolicy(0, mock_brain, trainer_config, False, False)
              if trainer_config["trainer"] == "ppo" else SACPolicy(
                  0, mock_brain, trainer_config, False, False))
    return policy
예제 #11
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def create_ppo_policy_mock(
    mock_env, dummy_config, reward_signal_config, use_rnn, use_discrete, use_visual
):

    if not use_visual:
        mock_brain = mb.create_mock_brainparams(
            vector_action_space_type="discrete" if use_discrete else "continuous",
            vector_action_space_size=DISCRETE_ACTION_SPACE
            if use_discrete
            else VECTOR_ACTION_SPACE,
            vector_observation_space_size=VECTOR_OBS_SPACE,
        )
        mock_braininfo = mb.create_mock_braininfo(
            num_agents=NUM_AGENTS,
            num_vector_observations=VECTOR_OBS_SPACE,
            num_vector_acts=sum(
                DISCRETE_ACTION_SPACE if use_discrete else VECTOR_ACTION_SPACE
            ),
            discrete=use_discrete,
        )
    else:
        mock_brain = mb.create_mock_brainparams(
            vector_action_space_type="discrete" if use_discrete else "continuous",
            vector_action_space_size=DISCRETE_ACTION_SPACE
            if use_discrete
            else VECTOR_ACTION_SPACE,
            vector_observation_space_size=0,
            number_visual_observations=1,
        )
        mock_braininfo = mb.create_mock_braininfo(
            num_agents=NUM_AGENTS,
            num_vis_observations=1,
            num_vector_acts=sum(
                DISCRETE_ACTION_SPACE if use_discrete else VECTOR_ACTION_SPACE
            ),
            discrete=use_discrete,
        )
    mb.setup_mock_unityenvironment(mock_env, mock_brain, mock_braininfo)
    env = mock_env()

    trainer_parameters = dummy_config
    model_path = env.brain_names[0]
    trainer_parameters["model_path"] = model_path
    trainer_parameters["keep_checkpoints"] = 3
    trainer_parameters["reward_signals"].update(reward_signal_config)
    trainer_parameters["use_recurrent"] = use_rnn
    policy = PPOPolicy(0, mock_brain, trainer_parameters, False, False)
    return env, policy
예제 #12
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def create_ppo_policy_with_bc_mock(mock_env, mock_brain, dummy_config, use_rnn,
                                   demo_file):
    mock_braininfo = mb.create_mock_braininfo(num_agents=12,
                                              num_vector_observations=8)
    mb.setup_mock_unityenvironment(mock_env, mock_brain, mock_braininfo)
    env = mock_env()

    trainer_parameters = dummy_config
    model_path = env.brain_names[0]
    trainer_parameters["model_path"] = model_path
    trainer_parameters["keep_checkpoints"] = 3
    trainer_parameters["use_recurrent"] = use_rnn
    trainer_parameters["pretraining"]["demo_path"] = (
        os.path.dirname(os.path.abspath(__file__)) + "/" + demo_file)
    policy = PPOPolicy(0, mock_brain, trainer_parameters, False, False)
    return env, policy
예제 #13
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def create_policy_with_bc_mock(mock_env, mock_brain, trainer_config, use_rnn,
                               demo_file):
    mock_braininfo = mb.create_mock_braininfo(num_agents=12,
                                              num_vector_observations=8)
    mb.setup_mock_unityenvironment(mock_env, mock_brain, mock_braininfo)
    env = mock_env()

    model_path = env.external_brain_names[0]
    trainer_config["model_path"] = model_path
    trainer_config["keep_checkpoints"] = 3
    trainer_config["use_recurrent"] = use_rnn
    trainer_config["behavioral_cloning"]["demo_path"] = (
        os.path.dirname(os.path.abspath(__file__)) + "/" + demo_file)

    policy = (PPOPolicy(0, mock_brain, trainer_config, False, False)
              if trainer_config["trainer"] == "ppo" else SACPolicy(
                  0, mock_brain, trainer_config, False, False))
    return env, policy
예제 #14
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def test_ppo_get_value_estimates(mock_communicator, mock_launcher,
                                 dummy_config):
    tf.reset_default_graph()

    brain_params = BrainParameters(
        brain_name="test_brain",
        vector_observation_space_size=1,
        camera_resolutions=[],
        vector_action_space_size=[2],
        vector_action_descriptions=[],
        vector_action_space_type=0,
    )
    dummy_config["summary_path"] = "./summaries/test_trainer_summary"
    dummy_config["model_path"] = "./models/test_trainer_models/TestModel"
    policy = PPOPolicy(0, brain_params, dummy_config, False, False)
    time_horizon = 15
    trajectory = make_fake_trajectory(
        length=time_horizon,
        max_step_complete=True,
        vec_obs_size=1,
        num_vis_obs=0,
        action_space=[2],
    )
    run_out = policy.get_value_estimates(trajectory.next_obs,
                                         "test_agent",
                                         done=False)
    for key, val in run_out.items():
        assert type(key) is str
        assert type(val) is float

    run_out = policy.get_value_estimates(trajectory.next_obs,
                                         "test_agent",
                                         done=True)
    for key, val in run_out.items():
        assert type(key) is str
        assert val == 0.0

    # Check if we ignore terminal states properly
    policy.reward_signals["extrinsic"].use_terminal_states = False
    run_out = policy.get_value_estimates(trajectory.next_obs,
                                         "test_agent",
                                         done=True)
    for key, val in run_out.items():
        assert type(key) is str
        assert val != 0.0

    agentbuffer = trajectory.to_agentbuffer()
    batched_values = policy.get_batched_value_estimates(agentbuffer)
    for values in batched_values.values():
        assert len(values) == 15
예제 #15
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def create_policy_mock(trainer_config, reward_signal_config, use_rnn,
                       use_discrete, use_visual):
    mock_brain = mb.setup_mock_brain(
        use_discrete,
        use_visual,
        vector_action_space=VECTOR_ACTION_SPACE,
        vector_obs_space=VECTOR_OBS_SPACE,
        discrete_action_space=DISCRETE_ACTION_SPACE,
    )

    trainer_parameters = trainer_config
    model_path = "testpath"
    trainer_parameters["model_path"] = model_path
    trainer_parameters["keep_checkpoints"] = 3
    trainer_parameters["reward_signals"].update(reward_signal_config)
    trainer_parameters["use_recurrent"] = use_rnn
    if trainer_config["trainer"] == "ppo":
        policy = PPOPolicy(0, mock_brain, trainer_parameters, False, False)
    else:
        policy = SACPolicy(0, mock_brain, trainer_parameters, False, False)
    return policy
예제 #16
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def create_policy_mock(mock_env, trainer_config, reward_signal_config, use_rnn,
                       use_discrete, use_visual):
    env, mock_brain, _ = mb.setup_mock_env_and_brains(
        mock_env,
        use_discrete,
        use_visual,
        num_agents=NUM_AGENTS,
        vector_action_space=VECTOR_ACTION_SPACE,
        vector_obs_space=VECTOR_OBS_SPACE,
        discrete_action_space=DISCRETE_ACTION_SPACE,
    )

    trainer_parameters = trainer_config
    model_path = env.external_brain_names[0]
    trainer_parameters["model_path"] = model_path
    trainer_parameters["keep_checkpoints"] = 3
    trainer_parameters["reward_signals"].update(reward_signal_config)
    trainer_parameters["use_recurrent"] = use_rnn
    if trainer_config["trainer"] == "ppo":
        policy = PPOPolicy(0, mock_brain, trainer_parameters, False, False)
    else:
        policy = SACPolicy(0, mock_brain, trainer_parameters, False, False)
    return env, policy
예제 #17
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    def __init__(self, brain, reward_buff_cap, trainer_parameters, training,
                 load, seed, run_id):
        """
        Responsible for collecting experiences and training PPO model.
        :param trainer_parameters: The parameters for the trainer (dictionary).
        :param training: Whether the trainer is set for training.
        :param load: Whether the model should be loaded.
        :param seed: The seed the model will be initialized with
        :param run_id: The identifier of the current run
        """
        super(PPOTrainer, self).__init__(brain, trainer_parameters, training,
                                         run_id)
        self.param_keys = [
            "batch_size",
            "beta",
            "buffer_size",
            "epsilon",
            "gamma",
            "hidden_units",
            "lambd",
            "learning_rate",
            "max_steps",
            "normalize",
            "num_epoch",
            "num_layers",
            "time_horizon",
            "sequence_length",
            "summary_freq",
            "use_recurrent",
            "summary_path",
            "memory_size",
            "use_curiosity",
            "curiosity_strength",
            "curiosity_enc_size",
            "model_path",
        ]

        self.check_param_keys()
        self.use_curiosity = bool(trainer_parameters["use_curiosity"])
        self.step = 0
        self.policy = PPOPolicy(seed, brain, trainer_parameters,
                                self.is_training, load)

        stats = {
            "Environment/Cumulative Reward": [],
            "Environment/Episode Length": [],
            "Policy/Value Estimate": [],
            "Policy/Entropy": [],
            "Losses/Value Loss": [],
            "Losses/Policy Loss": [],
            "Policy/Learning Rate": [],
        }
        if self.use_curiosity:
            stats["Losses/Forward Loss"] = []
            stats["Losses/Inverse Loss"] = []
            stats["Policy/Curiosity Reward"] = []
            self.intrinsic_rewards = {}
        self.stats = stats

        self.training_buffer = Buffer()
        self.cumulative_rewards = {}
        self._reward_buffer = deque(maxlen=reward_buff_cap)
        self.episode_steps = {}
class PPOTrainer(Trainer):
    """The PPOTrainer is an implementation of the PPO algorithm."""
    def __init__(self, brain, reward_buff_cap, trainer_parameters, training,
                 load, seed, run_id):
        """
        Responsible for collecting experiences and training PPO model.
        :param trainer_parameters: The parameters for the trainer (dictionary).
        :param reward_buff_cap: Max reward history to track in the reward buffer
        :param training: Whether the trainer is set for training.
        :param load: Whether the model should be loaded.
        :param seed: The seed the model will be initialized with
        :param run_id: The identifier of the current run
        """
        super().__init__(brain, trainer_parameters, training, run_id,
                         reward_buff_cap)
        self.param_keys = [
            "batch_size",
            "beta",
            "buffer_size",
            "epsilon",
            "hidden_units",
            "lambd",
            "learning_rate",
            "max_steps",
            "normalize",
            "num_epoch",
            "num_layers",
            "time_horizon",
            "sequence_length",
            "summary_freq",
            "use_recurrent",
            "summary_path",
            "memory_size",
            "model_path",
            "reward_signals",
        ]
        self.check_param_keys()

        # Make sure we have at least one reward_signal
        if not self.trainer_parameters["reward_signals"]:
            raise UnityTrainerException(
                "No reward signals were defined. At least one must be used with {}."
                .format(self.__class__.__name__))

        self.step = 0
        self.policy = PPOPolicy(seed, brain, trainer_parameters,
                                self.is_training, load)

        stats = defaultdict(list)
        # collected_rewards is a dictionary from name of reward signal to a dictionary of agent_id to cumulative reward
        # used for reporting only. We always want to report the environment reward to Tensorboard, regardless
        # of what reward signals are actually present.
        self.collected_rewards = {"environment": {}}
        for _reward_signal in self.policy.reward_signals.keys():
            self.collected_rewards[_reward_signal] = {}

        self.stats = stats

        self.training_buffer = Buffer()
        self.episode_steps = {}

    def __str__(self):
        return """Hyperparameters for the {0} of brain {1}: \n{2}""".format(
            self.__class__.__name__,
            self.brain_name,
            self.dict_to_str(self.trainer_parameters, 0),
        )

    @property
    def parameters(self):
        """
        Returns the trainer parameters of the trainer.
        """
        return self.trainer_parameters

    @property
    def get_max_steps(self):
        """
        Returns the maximum number of steps. Is used to know when the trainer should be stopped.
        :return: The maximum number of steps of the trainer
        """
        return float(self.trainer_parameters["max_steps"])

    @property
    def get_step(self):
        """
        Returns the number of steps the trainer has performed
        :return: the step count of the trainer
        """
        return self.step

    def increment_step(self, n_steps: int) -> None:
        """
        Increment the step count of the trainer

        :param n_steps: number of steps to increment the step count by
        """
        self.step = self.policy.increment_step(n_steps)

    def construct_curr_info(self, next_info: BrainInfo) -> BrainInfo:
        """
        Constructs a BrainInfo which contains the most recent previous experiences for all agents
        which correspond to the agents in a provided next_info.
        :BrainInfo next_info: A t+1 BrainInfo.
        :return: curr_info: Reconstructed BrainInfo to match agents of next_info.
        """
        visual_observations: List[List[Any]] = [
            []
        ]  # TODO add types to brain.py methods
        vector_observations = []
        text_observations = []
        memories = []
        rewards = []
        local_dones = []
        max_reacheds = []
        agents = []
        prev_vector_actions = []
        prev_text_actions = []
        action_masks = []
        for agent_id in next_info.agents:
            agent_brain_info = self.training_buffer[agent_id].last_brain_info
            if agent_brain_info is None:
                agent_brain_info = next_info
            agent_index = agent_brain_info.agents.index(agent_id)
            for i in range(len(next_info.visual_observations)):
                visual_observations[i].append(
                    agent_brain_info.visual_observations[i][agent_index])
            vector_observations.append(
                agent_brain_info.vector_observations[agent_index])
            text_observations.append(
                agent_brain_info.text_observations[agent_index])
            if self.policy.use_recurrent:
                if len(agent_brain_info.memories) > 0:
                    memories.append(agent_brain_info.memories[agent_index])
                else:
                    memories.append(self.policy.make_empty_memory(1))
            rewards.append(agent_brain_info.rewards[agent_index])
            local_dones.append(agent_brain_info.local_done[agent_index])
            max_reacheds.append(agent_brain_info.max_reached[agent_index])
            agents.append(agent_brain_info.agents[agent_index])
            prev_vector_actions.append(
                agent_brain_info.previous_vector_actions[agent_index])
            prev_text_actions.append(
                agent_brain_info.previous_text_actions[agent_index])
            action_masks.append(agent_brain_info.action_masks[agent_index])
        if self.policy.use_recurrent:
            memories = np.vstack(memories)
        curr_info = BrainInfo(
            visual_observations,
            vector_observations,
            text_observations,
            memories,
            rewards,
            agents,
            local_dones,
            prev_vector_actions,
            prev_text_actions,
            max_reacheds,
            action_masks,
        )
        return curr_info

    def add_experiences(
        self,
        curr_all_info: AllBrainInfo,
        next_all_info: AllBrainInfo,
        take_action_outputs: ActionInfoOutputs,
    ) -> None:
        """
        Adds experiences to each agent's experience history.
        :param curr_all_info: Dictionary of all current brains and corresponding BrainInfo.
        :param next_all_info: Dictionary of all current brains and corresponding BrainInfo.
        :param take_action_outputs: The outputs of the Policy's get_action method.
        """
        self.trainer_metrics.start_experience_collection_timer()
        if take_action_outputs:
            self.stats["Policy/Entropy"].append(
                take_action_outputs["entropy"].mean())
            self.stats["Policy/Learning Rate"].append(
                take_action_outputs["learning_rate"])
            for name, signal in self.policy.reward_signals.items():
                self.stats[signal.value_name].append(
                    np.mean(take_action_outputs["value"][name]))

        curr_info = curr_all_info[self.brain_name]
        next_info = next_all_info[self.brain_name]

        for agent_id in curr_info.agents:
            self.training_buffer[agent_id].last_brain_info = curr_info
            self.training_buffer[
                agent_id].last_take_action_outputs = take_action_outputs

        if curr_info.agents != next_info.agents:
            curr_to_use = self.construct_curr_info(next_info)
        else:
            curr_to_use = curr_info

        tmp_rewards_dict = {}
        for name, signal in self.policy.reward_signals.items():
            tmp_rewards_dict[name] = signal.evaluate(curr_to_use, next_info)

        for agent_id in next_info.agents:
            stored_info = self.training_buffer[agent_id].last_brain_info
            stored_take_action_outputs = self.training_buffer[
                agent_id].last_take_action_outputs
            if stored_info is not None:
                idx = stored_info.agents.index(agent_id)
                next_idx = next_info.agents.index(agent_id)
                if not stored_info.local_done[idx]:
                    for i, _ in enumerate(stored_info.visual_observations):
                        self.training_buffer[agent_id][
                            "visual_obs%d" % i].append(
                                stored_info.visual_observations[i][idx])
                        self.training_buffer[agent_id][
                            "next_visual_obs%d" % i].append(
                                next_info.visual_observations[i][next_idx])
                    if self.policy.use_vec_obs:
                        self.training_buffer[agent_id]["vector_obs"].append(
                            stored_info.vector_observations[idx])
                        self.training_buffer[agent_id][
                            "next_vector_in"].append(
                                next_info.vector_observations[next_idx])
                    if self.policy.use_recurrent:
                        if stored_info.memories.shape[1] == 0:
                            stored_info.memories = np.zeros(
                                (len(stored_info.agents), self.policy.m_size))
                        self.training_buffer[agent_id]["memory"].append(
                            stored_info.memories[idx])
                    actions = stored_take_action_outputs["action"]
                    if self.policy.use_continuous_act:
                        actions_pre = stored_take_action_outputs["pre_action"]
                        self.training_buffer[agent_id]["actions_pre"].append(
                            actions_pre[idx])
                        epsilons = stored_take_action_outputs[
                            "random_normal_epsilon"]
                        self.training_buffer[agent_id][
                            "random_normal_epsilon"].append(epsilons[idx])
                    else:
                        self.training_buffer[agent_id]["action_mask"].append(
                            stored_info.action_masks[idx], padding_value=1)
                    a_dist = stored_take_action_outputs["log_probs"]
                    # value is a dictionary from name of reward to value estimate of the value head
                    value = stored_take_action_outputs["value"]
                    self.training_buffer[agent_id]["actions"].append(
                        actions[idx])
                    self.training_buffer[agent_id]["prev_action"].append(
                        stored_info.previous_vector_actions[idx])
                    self.training_buffer[agent_id]["masks"].append(1.0)
                    self.training_buffer[agent_id]["done"].append(
                        next_info.local_done[next_idx])

                    for name, reward_result in tmp_rewards_dict.items():
                        # 0 because we use the scaled reward to train the agent
                        self.training_buffer[agent_id]["{}_rewards".format(
                            name)].append(
                                reward_result.scaled_reward[next_idx])
                        self.training_buffer[agent_id][
                            "{}_value_estimates".format(name)].append(
                                value[name][idx][0])

                    self.training_buffer[agent_id]["action_probs"].append(
                        a_dist[idx])

                    for name, rewards in self.collected_rewards.items():
                        if agent_id not in rewards:
                            rewards[agent_id] = 0
                        if name == "environment":
                            # Report the reward from the environment
                            rewards[agent_id] += np.array(
                                next_info.rewards)[next_idx]
                        else:
                            # Report the reward signals
                            rewards[agent_id] += tmp_rewards_dict[
                                name].scaled_reward[next_idx]

                if not next_info.local_done[next_idx]:
                    if agent_id not in self.episode_steps:
                        self.episode_steps[agent_id] = 0
                    self.episode_steps[agent_id] += 1
        self.trainer_metrics.end_experience_collection_timer()

    def process_experiences(self, current_info: AllBrainInfo,
                            new_info: AllBrainInfo) -> None:
        """
        Checks agent histories for processing condition, and processes them as necessary.
        Processing involves calculating value and advantage targets for model updating step.
        :param current_info: Dictionary of all current brains and corresponding BrainInfo.
        :param new_info: Dictionary of all next brains and corresponding BrainInfo.
        """
        info = new_info[self.brain_name]
        for l in range(len(info.agents)):
            agent_actions = self.training_buffer[info.agents[l]]["actions"]
            if (info.local_done[l] or len(agent_actions) >
                    self.trainer_parameters["time_horizon"]
                ) and len(agent_actions) > 0:
                agent_id = info.agents[l]
                if info.max_reached[l]:
                    bootstrapping_info = self.training_buffer[
                        agent_id].last_brain_info
                    idx = bootstrapping_info.agents.index(agent_id)
                else:
                    bootstrapping_info = info
                    idx = l
                value_next = self.policy.get_value_estimates(
                    bootstrapping_info,
                    idx,
                    info.local_done[l] and not info.max_reached[l],
                )

                tmp_advantages = []
                tmp_returns = []
                for name in self.policy.reward_signals:
                    bootstrap_value = value_next[name]

                    local_rewards = self.training_buffer[agent_id][
                        "{}_rewards".format(name)].get_batch()
                    local_value_estimates = self.training_buffer[agent_id][
                        "{}_value_estimates".format(name)].get_batch()
                    local_advantage = get_gae(
                        rewards=local_rewards,
                        value_estimates=local_value_estimates,
                        value_next=bootstrap_value,
                        gamma=self.policy.reward_signals[name].gamma,
                        lambd=self.trainer_parameters["lambd"],
                    )
                    local_return = local_advantage + local_value_estimates
                    # This is later use as target for the different value estimates
                    self.training_buffer[agent_id]["{}_returns".format(
                        name)].set(local_return)
                    self.training_buffer[agent_id]["{}_advantage".format(
                        name)].set(local_advantage)
                    tmp_advantages.append(local_advantage)
                    tmp_returns.append(local_return)

                global_advantages = list(
                    np.mean(np.array(tmp_advantages), axis=0))
                global_returns = list(np.mean(np.array(tmp_returns), axis=0))
                self.training_buffer[agent_id]["advantages"].set(
                    global_advantages)
                self.training_buffer[agent_id]["discounted_returns"].set(
                    global_returns)

                self.training_buffer.append_update_buffer(
                    agent_id,
                    batch_size=None,
                    training_length=self.policy.sequence_length,
                )

                self.training_buffer[agent_id].reset_agent()
                if info.local_done[l]:
                    self.stats["Environment/Episode Length"].append(
                        self.episode_steps.get(agent_id, 0))
                    self.episode_steps[agent_id] = 0
                    for name, rewards in self.collected_rewards.items():
                        if name == "environment":
                            self.cumulative_returns_since_policy_update.append(
                                rewards.get(agent_id, 0))
                            self.stats["Environment/Cumulative Reward"].append(
                                rewards.get(agent_id, 0))
                            self.reward_buffer.appendleft(
                                rewards.get(agent_id, 0))
                            rewards[agent_id] = 0
                        else:
                            self.stats[self.policy.reward_signals[name].
                                       stat_name].append(
                                           rewards.get(agent_id, 0))
                            rewards[agent_id] = 0

    def end_episode(self):
        """
        A signal that the Episode has ended. The buffer must be reset.
        Get only called when the academy resets.
        """
        self.training_buffer.reset_local_buffers()
        for agent_id in self.episode_steps:
            self.episode_steps[agent_id] = 0
        for rewards in self.collected_rewards.values():
            for agent_id in rewards:
                rewards[agent_id] = 0

    def is_ready_update(self):
        """
        Returns whether or not the trainer has enough elements to run update model
        :return: A boolean corresponding to whether or not update_model() can be run
        """
        size_of_buffer = len(self.training_buffer.update_buffer["actions"])
        return size_of_buffer > max(
            int(self.trainer_parameters["buffer_size"] /
                self.policy.sequence_length), 1)

    def update_policy(self):
        """
        Uses demonstration_buffer to update the policy.
        The reward signal generators must be updated in this method at their own pace.
        """
        self.trainer_metrics.start_policy_update_timer(
            number_experiences=len(
                self.training_buffer.update_buffer["actions"]),
            mean_return=float(
                np.mean(self.cumulative_returns_since_policy_update)),
        )
        self.cumulative_returns_since_policy_update = []
        n_sequences = max(
            int(self.trainer_parameters["batch_size"] /
                self.policy.sequence_length), 1)
        value_total, policy_total = [], []
        advantages = self.training_buffer.update_buffer[
            "advantages"].get_batch()
        self.training_buffer.update_buffer["advantages"].set(
            (advantages - advantages.mean()) / (advantages.std() + 1e-10))
        num_epoch = self.trainer_parameters["num_epoch"]
        for _ in range(num_epoch):
            self.training_buffer.update_buffer.shuffle()
            buffer = self.training_buffer.update_buffer
            for l in range(
                    len(self.training_buffer.update_buffer["actions"]) //
                    n_sequences):
                start = l * n_sequences
                end = (l + 1) * n_sequences
                run_out = self.policy.update(
                    buffer.make_mini_batch(start, end), n_sequences)
                value_total.append(run_out["value_loss"])
                policy_total.append(np.abs(run_out["policy_loss"]))
        self.stats["Losses/Value Loss"].append(np.mean(value_total))
        self.stats["Losses/Policy Loss"].append(np.mean(policy_total))
        for _, reward_signal in self.policy.reward_signals.items():
            update_stats = reward_signal.update(
                self.training_buffer.update_buffer, n_sequences)
            for stat, val in update_stats.items():
                self.stats[stat].append(val)
        if self.policy.bc_module:
            update_stats = self.policy.bc_module.update()
            for stat, val in update_stats.items():
                self.stats[stat].append(val)
        self.training_buffer.reset_update_buffer()
        self.trainer_metrics.end_policy_update()
예제 #19
0
class PPOTrainer(Trainer):
    """The PPOTrainer is an implementation of the PPO algorithm."""
    def __init__(self, sess, brain, reward_buff_cap, trainer_parameters,
                 training, seed, run_id):
        """
        Responsible for collecting experiences and training PPO model.
        :param sess: Tensorflow session.
        :param  trainer_parameters: The parameters for the trainer (dictionary).
        :param training: Whether the trainer is set for training.
        """
        super(PPOTrainer, self).__init__(sess, brain.brain_name,
                                         trainer_parameters, training, run_id)

        self.param_keys = [
            'batch_size', 'beta', 'buffer_size', 'epsilon', 'gamma',
            'hidden_units', 'lambd', 'learning_rate', 'max_steps', 'normalize',
            'num_epoch', 'num_layers', 'time_horizon', 'sequence_length',
            'summary_freq', 'use_recurrent', 'graph_scope', 'summary_path',
            'memory_size', 'use_curiosity', 'curiosity_strength',
            'curiosity_enc_size'
        ]

        for k in self.param_keys:
            if k not in trainer_parameters:
                raise UnityTrainerException(
                    "The hyperparameter {0} could not be found for the PPO trainer of "
                    "brain {1}.".format(k, brain.brain_name))

        self.use_curiosity = bool(trainer_parameters['use_curiosity'])

        self.step = 0

        self.policy = PPOPolicy(seed, brain, trainer_parameters, sess,
                                self.is_training)

        stats = {
            'cumulative_reward': [],
            'episode_length': [],
            'value_estimate': [],
            'entropy': [],
            'value_loss': [],
            'policy_loss': [],
            'learning_rate': []
        }
        if self.use_curiosity:
            stats['forward_loss'] = []
            stats['inverse_loss'] = []
            stats['intrinsic_reward'] = []
            self.intrinsic_rewards = {}
        self.stats = stats

        self.training_buffer = Buffer()
        self.training_buffer2 = Buffer()

        self.cumulative_rewards = {}
        self._reward_buffer = deque(maxlen=reward_buff_cap)
        self.episode_steps = {}
        self.summary_path = trainer_parameters['summary_path']
        if not os.path.exists(self.summary_path):
            os.makedirs(self.summary_path)

        self.summary_writer = tf.summary.FileWriter(self.summary_path)

    def __str__(self):
        return '''Hyperparameters for the PPO Trainer of brain {0}: \n{1}'''.format(
            self.brain_name, '\n'.join([
                '\t{0}:\t{1}'.format(x, self.trainer_parameters[x])
                for x in self.param_keys
            ]))

    @property
    def parameters(self):
        """
        Returns the trainer parameters of the trainer.
        """
        return self.trainer_parameters

    @property
    def get_max_steps(self):
        """
        Returns the maximum number of steps. Is used to know when the trainer should be stopped.
        :return: The maximum number of steps of the trainer
        """
        return float(self.trainer_parameters['max_steps'])

    @property
    def get_step(self):
        """
        Returns the number of steps the trainer has performed
        :return: the step count of the trainer
        """
        return self.step

    @property
    def reward_buffer(self):
        """
        Returns the reward buffer. The reward buffer contains the cumulative
        rewards of the most recent episodes completed by agents using this
        trainer.
        :return: the reward buffer.
        """
        return self._reward_buffer

    def increment_step_and_update_last_reward(self):
        """
        Increment the step count of the trainer and Updates the last reward
        """
        if len(self.stats['cumulative_reward']) > 0:
            mean_reward = np.mean(self.stats['cumulative_reward'])
            self.policy.update_reward(mean_reward)
        self.policy.increment_step()
        self.step = self.policy.get_current_step()

    def take_action(self, all_brain_info: AllBrainInfo):
        """
        Decides actions given observations information, and takes them in environment.
        :param all_brain_info: A dictionary of brain names and BrainInfo from environment.
        :return: a tuple containing action, memories, values and an object
        to be passed to add experiences
        """
        curr_brain_info = all_brain_info[self.brain_name]
        if len(curr_brain_info.agents) == 0:
            return [], [], [], None, None

        run_out = self.policy.evaluate(curr_brain_info)
        self.stats['value_estimate'].append(run_out['value'].mean())
        self.stats['entropy'].append(run_out['entropy'].mean())
        self.stats['learning_rate'].append(run_out['learning_rate'])
        if self.policy.use_recurrent:
            return run_out['action'], run_out['memory_out'], None, \
                   run_out['value'], run_out
        else:
            return run_out['action'], None, None, run_out['value'], run_out

    def construct_curr_info(self, next_info: BrainInfo) -> BrainInfo:
        """
        Constructs a BrainInfo which contains the most recent previous experiences for all agents info
        which correspond to the agents in a provided next_info.
        :BrainInfo next_info: A t+1 BrainInfo.
        :return: curr_info: Reconstructed BrainInfo to match agents of next_info.
        """
        visual_observations = [[]]
        vector_observations = []
        text_observations = []
        memories = []
        rewards = []
        local_dones = []
        max_reacheds = []
        agents = []
        prev_vector_actions = []
        prev_text_actions = []
        for agent_id in next_info.agents:
            agent_brain_info = self.training_buffer[agent_id].last_brain_info
            if agent_brain_info is None:
                agent_brain_info = next_info
            agent_index = agent_brain_info.agents.index(agent_id)
            for i in range(len(next_info.visual_observations)):
                visual_observations[i].append(
                    agent_brain_info.visual_observations[i][agent_index])
            vector_observations.append(
                agent_brain_info.vector_observations[agent_index])
            text_observations.append(
                agent_brain_info.text_observations[agent_index])
            if self.policy.use_recurrent:
                if len(agent_brain_info.memories > 0):
                    memories.append(agent_brain_info.memories[agent_index])
                else:
                    memories.append(self.policy.make_empty_memory(1))
            rewards.append(agent_brain_info.rewards[agent_index])
            local_dones.append(agent_brain_info.local_done[agent_index])
            max_reacheds.append(agent_brain_info.max_reached[agent_index])
            agents.append(agent_brain_info.agents[agent_index])
            prev_vector_actions.append(
                agent_brain_info.previous_vector_actions[agent_index])
            prev_text_actions.append(
                agent_brain_info.previous_text_actions[agent_index])
        if self.policy.use_recurrent:
            memories = np.vstack(memories)
        curr_info = BrainInfo(visual_observations, vector_observations,
                              text_observations, memories, rewards, agents,
                              local_dones, prev_vector_actions,
                              prev_text_actions, max_reacheds)
        return curr_info

    def construct_curr_info2(self, next_info: BrainInfo) -> BrainInfo:
        """
        Constructs a BrainInfo which contains the most recent previous experiences for all agents info
        which correspond to the agents in a provided next_info.
        :BrainInfo next_info: A t+1 BrainInfo.
        :return: curr_info: Reconstructed BrainInfo to match agents of next_info.
        """
        visual_observations = [[]]
        vector_observations2 = []
        text_observations = []
        memories = []
        rewards = []
        local_dones = []
        max_reacheds = []
        agents = []
        prev_vector_actions = []
        prev_text_actions = []

        for agent_id in next_info.agents:
            agent_brain_info = self.training_buffer[agent_id].last_brain_info
            agent_brain_info2 = next_info

            agent_index1 = agent_brain_info.agents.index(agent_id)
            agent_index2 = agent_brain_info2.agents.index(agent_id)

            for i in range(len(next_info.visual_observations)):
                visual_observations[i].append(
                    agent_brain_info.visual_observations[i][agent_index])

            vector_observations2.append(
                agent_brain_info.vector_observations[agent_index1],
                agent_brain_info2.vector_observations[agent_index2])

            text_observations.append(
                agent_brain_info.text_observations[agent_index])

            if self.policy.use_recurrent:
                if len(agent_brain_info.memories > 0):
                    memories.append(agent_brain_info.memories[agent_index])
                else:
                    memories.append(self.policy.make_empty_memory(1))
            rewards.append(agent_brain_info.rewards[agent_index])
            local_dones.append(agent_brain_info.local_done[agent_index])
            max_reacheds.append(agent_brain_info.max_reached[agent_index])
            agents.append(agent_brain_info.agents[agent_index])
            prev_vector_actions.append(
                agent_brain_info.previous_vector_actions[agent_index])
            prev_text_actions.append(
                agent_brain_info.previous_text_actions[agent_index])
        if self.policy.use_recurrent:
            memories = np.vstack(memories)

        curr_info2 = BrainInfo(visual_observations, vector_observations2,
                               text_observations, memories, rewards, agents,
                               local_dones, prev_vector_actions,
                               prev_text_actions, max_reacheds)
        return curr_info2

    def add_experiences(self, curr_all_info: AllBrainInfo,
                        next_all_info: AllBrainInfo, take_action_outputs):
        """
        Adds experiences to each agent's experience history.
        :param curr_all_info: Dictionary of all current brains and corresponding BrainInfo.
        :param next_all_info: Dictionary of all current brains and corresponding BrainInfo.
        :param take_action_outputs: The outputs of the take action method.
        """
        curr_info = curr_all_info[self.brain_name]
        curr_info2 = curr_all_info[self.brain_name]

        next_info = next_all_info[self.brain_name]

        for agent_id in curr_info.agents:
            self.training_buffer[agent_id].last_brain_info = curr_info
            self.training_buffer[
                agent_id].last_take_action_outputs = take_action_outputs

        for agent_id in curr_info2.agents:
            self.training_buffer2[agent_id].last_brain_info = curr_info2
            self.training_buffer2[
                agent_id].last_take_action_outputs = take_action_outputs

        if curr_info.agents != next_info.agents:
            curr_to_use = self.construct_curr_info(next_info)
        else:
            curr_to_use = curr_info

        intrinsic_rewards = self.policy.get_intrinsic_rewards(
            curr_to_use, next_info)

        for agent_id in next_info.agents:
            stored_info = self.training_buffer[agent_id].last_brain_info

            stored_take_action_outputs = self.training_buffer[
                agent_id].last_take_action_outputs
            stored_take_action_outputs2 = self.training_buffer2[
                agent_id].last_take_action_outputs

            if stored_info is not None:
                idx = stored_info.agents.index(agent_id)
                next_idx = next_info.agents.index(agent_id)
                if not stored_info.local_done[idx]:
                    for i, _ in enumerate(stored_info.visual_observations):
                        self.training_buffer[agent_id][
                            'visual_obs%d' % i].append(
                                stored_info.visual_observations[i][idx])
                        self.training_buffer[agent_id][
                            'next_visual_obs%d' % i].append(
                                next_info.visual_observations[i][next_idx])
                    if self.policy.use_vec_obs:
                        self.training_buffer[agent_id]['vector_obs'].append(
                            stored_info.vector_observations[idx])
                        self.training_buffer[agent_id][
                            'next_vector_in'].append(
                                next_info.vector_observations[next_idx])
                    if self.policy.use_recurrent:
                        if stored_info.memories.shape[1] == 0:
                            stored_info.memories = np.zeros(
                                (len(stored_info.agents), self.policy.m_size))
                        self.training_buffer[agent_id]['memory'].append(
                            stored_info.memories[idx])
                    actions = stored_take_action_outputs['action']
                    if self.policy.use_continuous_act:
                        actions_pre = stored_take_action_outputs['pre_action']
                        self.training_buffer[agent_id]['actions_pre'].append(
                            actions_pre[idx])
                    else:
                        self.training_buffer[agent_id]['action_mask'].append(
                            stored_info.action_masks[idx])
                    a_dist = stored_take_action_outputs['log_probs']

                    value1 = stored_take_action_outputs['value']
                    value2 = stored_take_action_outputs2['value']

                    if sum(value1) > sum(value2):
                        value = value1
                    else:
                        value = value2

                    self.training_buffer[agent_id]['actions'].append(
                        actions[idx])
                    self.training_buffer[agent_id]['prev_action'].append(
                        stored_info.previous_vector_actions[idx])
                    self.training_buffer[agent_id]['masks'].append(1.0)
                    if self.use_curiosity:
                        self.training_buffer[agent_id]['rewards'].append(
                            next_info.rewards[next_idx] +
                            intrinsic_rewards[next_idx])
                    else:
                        self.training_buffer[agent_id]['rewards'].append(
                            next_info.rewards[next_idx])
                    self.training_buffer[agent_id]['action_probs'].append(
                        a_dist[idx])
                    self.training_buffer[agent_id]['value_estimates'].append(
                        value[idx][0])
                    if agent_id not in self.cumulative_rewards:
                        self.cumulative_rewards[agent_id] = 0
                    self.cumulative_rewards[agent_id] += next_info.rewards[
                        next_idx]
                    if self.use_curiosity:
                        if agent_id not in self.intrinsic_rewards:
                            self.intrinsic_rewards[agent_id] = 0
                        self.intrinsic_rewards[agent_id] += intrinsic_rewards[
                            next_idx]
                if not next_info.local_done[next_idx]:
                    if agent_id not in self.episode_steps:
                        self.episode_steps[agent_id] = 0
                    self.episode_steps[agent_id] += 1

    def process_experiences(self, current_info: AllBrainInfo,
                            new_info: AllBrainInfo):
        """
        Checks agent histories for processing condition, and processes them as necessary.
        Processing involves calculating value and advantage targets for model updating step.
        :param current_info: Dictionary of all current brains and corresponding BrainInfo.
        :param new_info: Dictionary of all next brains and corresponding BrainInfo.
        """

        info = new_info[self.brain_name]
        for l in range(len(info.agents)):
            agent_actions = self.training_buffer[info.agents[l]]['actions']
            if ((info.local_done[l] or
                 len(agent_actions) > self.trainer_parameters['time_horizon'])
                    and len(agent_actions) > 0):
                agent_id = info.agents[l]
                if info.local_done[l] and not info.max_reached[l]:
                    value_next = 0.0
                else:
                    if info.max_reached[l]:
                        bootstrapping_info = self.training_buffer[
                            agent_id].last_brain_info
                        idx = bootstrapping_info.agents.index(agent_id)
                    else:
                        bootstrapping_info = info
                        idx = l
                    value_next = self.policy.get_value_estimate(
                        bootstrapping_info, idx)

                self.training_buffer[agent_id]['advantages'].set(
                    get_gae(rewards=self.training_buffer[agent_id]
                            ['rewards'].get_batch(),
                            value_estimates=self.training_buffer[agent_id]
                            ['value_estimates'].get_batch(),
                            value_next=value_next,
                            gamma=self.trainer_parameters['gamma'],
                            lambd=self.trainer_parameters['lambd']))
                self.training_buffer[agent_id]['discounted_returns'].set(
                    self.training_buffer[agent_id]['advantages'].get_batch() +
                    self.training_buffer[agent_id]
                    ['value_estimates'].get_batch())

                self.training_buffer.append_update_buffer(
                    agent_id,
                    batch_size=None,
                    training_length=self.policy.sequence_length)

                self.training_buffer[agent_id].reset_agent()
                if info.local_done[l]:
                    self.stats['cumulative_reward'].append(
                        self.cumulative_rewards.get(agent_id, 0))
                    self.reward_buffer.appendleft(
                        self.cumulative_rewards.get(agent_id, 0))
                    self.stats['episode_length'].append(
                        self.episode_steps.get(agent_id, 0))
                    self.cumulative_rewards[agent_id] = 0
                    self.episode_steps[agent_id] = 0
                    if self.use_curiosity:
                        self.stats['intrinsic_reward'].append(
                            self.intrinsic_rewards.get(agent_id, 0))
                        self.intrinsic_rewards[agent_id] = 0

    def end_episode(self):
        """
        A signal that the Episode has ended. The buffer must be reset. 
        Get only called when the academy resets.
        """
        self.training_buffer.reset_all()
        for agent_id in self.cumulative_rewards:
            self.cumulative_rewards[agent_id] = 0
        for agent_id in self.episode_steps:
            self.episode_steps[agent_id] = 0
        if self.use_curiosity:
            for agent_id in self.intrinsic_rewards:
                self.intrinsic_rewards[agent_id] = 0

    def is_ready_update(self):
        """
        Returns whether or not the trainer has enough elements to run update model
        :return: A boolean corresponding to whether or not update_model() can be run
        """
        size_of_buffer = len(self.training_buffer.update_buffer['actions'])
        return size_of_buffer > max(
            int(self.trainer_parameters['buffer_size'] /
                self.policy.sequence_length), 1)

    def update_policy(self):
        """
        Uses training_buffer to update the policy.
        """
        n_sequences = max(
            int(self.trainer_parameters['batch_size'] /
                self.policy.sequence_length), 1)
        value_total, policy_total, forward_total, inverse_total = [], [], [], []
        advantages = self.training_buffer.update_buffer[
            'advantages'].get_batch()
        self.training_buffer.update_buffer['advantages'].set(
            (advantages - advantages.mean()) / (advantages.std() + 1e-10))
        num_epoch = self.trainer_parameters['num_epoch']
        for k in range(num_epoch):
            self.training_buffer.update_buffer.shuffle()
            buffer = self.training_buffer.update_buffer
            for l in range(
                    len(self.training_buffer.update_buffer['actions']) //
                    n_sequences):
                start = l * n_sequences
                end = (l + 1) * n_sequences
                run_out = self.policy.update(
                    buffer.make_mini_batch(start, end), n_sequences)
                value_total.append(run_out['value_loss'])
                policy_total.append(np.abs(run_out['policy_loss']))
                if self.use_curiosity:
                    inverse_total.append(run_out['inverse_loss'])
                    forward_total.append(run_out['forward_loss'])
        self.stats['value_loss'].append(np.mean(value_total))
        self.stats['policy_loss'].append(np.mean(policy_total))
        if self.use_curiosity:
            self.stats['forward_loss'].append(np.mean(forward_total))
            self.stats['inverse_loss'].append(np.mean(inverse_total))
        self.training_buffer.reset_update_buffer()
예제 #20
0
class PPOTrainer(RLTrainer):
    """The PPOTrainer is an implementation of the PPO algorithm."""
    def __init__(
        self,
        brain,
        reward_buff_cap,
        trainer_parameters,
        training,
        load,
        seed,
        run_id,
        multi_gpu,
    ):
        """
        Responsible for collecting experiences and training PPO model.
        :param trainer_parameters: The parameters for the trainer (dictionary).
        :param reward_buff_cap: Max reward history to track in the reward buffer
        :param training: Whether the trainer is set for training.
        :param load: Whether the model should be loaded.
        :param seed: The seed the model will be initialized with
        :param run_id: The identifier of the current run
        """
        super(PPOTrainer, self).__init__(brain, trainer_parameters, training,
                                         run_id, reward_buff_cap)
        self.param_keys = [
            "batch_size",
            "beta",
            "buffer_size",
            "epsilon",
            "hidden_units",
            "lambd",
            "learning_rate",
            "max_steps",
            "normalize",
            "num_epoch",
            "num_layers",
            "time_horizon",
            "sequence_length",
            "summary_freq",
            "use_recurrent",
            "summary_path",
            "memory_size",
            "model_path",
            "reward_signals",
        ]
        self.check_param_keys()

        if multi_gpu and len(get_devices()) > 1:
            self.ppo_policy = MultiGpuPPOPolicy(seed, brain,
                                                trainer_parameters,
                                                self.is_training, load)
        else:
            self.ppo_policy = PPOPolicy(seed, brain, trainer_parameters,
                                        self.is_training, load)
        self.policy = self.ppo_policy

        for _reward_signal in self.policy.reward_signals.keys():
            self.collected_rewards[_reward_signal] = {}

    def process_experiences(self, current_info: BrainInfo,
                            next_info: BrainInfo) -> None:
        """
        Checks agent histories for processing condition, and processes them as necessary.
        Processing involves calculating value and advantage targets for model updating step.
        :param current_info: current BrainInfo.
        :param next_info: next BrainInfo.
        """
        if self.is_training:
            self.policy.update_normalization(next_info.vector_observations)
        for l in range(len(next_info.agents)):
            agent_actions = self.processing_buffer[
                next_info.agents[l]]["actions"]
            if (next_info.local_done[l] or len(agent_actions) >
                    self.trainer_parameters["time_horizon"]
                ) and len(agent_actions) > 0:
                agent_id = next_info.agents[l]
                if next_info.max_reached[l]:
                    bootstrapping_info = self.processing_buffer[
                        agent_id].last_brain_info
                    idx = bootstrapping_info.agents.index(agent_id)
                else:
                    bootstrapping_info = next_info
                    idx = l
                value_next = self.ppo_policy.get_value_estimates(
                    bootstrapping_info,
                    idx,
                    next_info.local_done[l] and not next_info.max_reached[l],
                )

                tmp_advantages = []
                tmp_returns = []
                for name in self.policy.reward_signals:
                    bootstrap_value = value_next[name]

                    local_rewards = self.processing_buffer[agent_id][
                        "{}_rewards".format(name)].get_batch()
                    local_value_estimates = self.processing_buffer[agent_id][
                        "{}_value_estimates".format(name)].get_batch()
                    local_advantage = get_gae(
                        rewards=local_rewards,
                        value_estimates=local_value_estimates,
                        value_next=bootstrap_value,
                        gamma=self.policy.reward_signals[name].gamma,
                        lambd=self.trainer_parameters["lambd"],
                    )
                    local_return = local_advantage + local_value_estimates
                    # This is later use as target for the different value estimates
                    self.processing_buffer[agent_id]["{}_returns".format(
                        name)].set(local_return)
                    self.processing_buffer[agent_id]["{}_advantage".format(
                        name)].set(local_advantage)
                    tmp_advantages.append(local_advantage)
                    tmp_returns.append(local_return)

                global_advantages = list(
                    np.mean(np.array(tmp_advantages, dtype=np.float32),
                            axis=0))
                global_returns = list(
                    np.mean(np.array(tmp_returns, dtype=np.float32), axis=0))
                self.processing_buffer[agent_id]["advantages"].set(
                    global_advantages)
                self.processing_buffer[agent_id]["discounted_returns"].set(
                    global_returns)

                self.processing_buffer.append_to_update_buffer(
                    self.update_buffer,
                    agent_id,
                    batch_size=None,
                    training_length=self.policy.sequence_length,
                )

                self.processing_buffer[agent_id].reset_agent()
                if next_info.local_done[l]:
                    self.stats["Environment/Episode Length"].append(
                        self.episode_steps.get(agent_id, 0))
                    self.episode_steps[agent_id] = 0
                    for name, rewards in self.collected_rewards.items():
                        if name == "environment":
                            self.cumulative_returns_since_policy_update.append(
                                rewards.get(agent_id, 0))
                            self.stats["Environment/Cumulative Reward"].append(
                                rewards.get(agent_id, 0))
                            self.reward_buffer.appendleft(
                                rewards.get(agent_id, 0))
                            rewards[agent_id] = 0
                        else:
                            self.stats[self.policy.reward_signals[name].
                                       stat_name].append(
                                           rewards.get(agent_id, 0))
                            rewards[agent_id] = 0

    def add_policy_outputs(self, take_action_outputs: ActionInfoOutputs,
                           agent_id: str, agent_idx: int) -> None:
        """
        Takes the output of the last action and store it into the training buffer.
        """
        actions = take_action_outputs["action"]
        if self.policy.use_continuous_act:
            actions_pre = take_action_outputs["pre_action"]
            self.processing_buffer[agent_id]["actions_pre"].append(
                actions_pre[agent_idx])
        a_dist = take_action_outputs["log_probs"]
        # value is a dictionary from name of reward to value estimate of the value head
        self.processing_buffer[agent_id]["actions"].append(actions[agent_idx])
        self.processing_buffer[agent_id]["action_probs"].append(
            a_dist[agent_idx])

    def add_rewards_outputs(
        self,
        rewards_out: AllRewardsOutput,
        values: Dict[str, np.ndarray],
        agent_id: str,
        agent_idx: int,
        agent_next_idx: int,
    ) -> None:
        """
        Takes the value output of the last action and store it into the training buffer.
        """
        for name, reward_result in rewards_out.reward_signals.items():
            # 0 because we use the scaled reward to train the agent
            self.processing_buffer[agent_id]["{}_rewards".format(name)].append(
                reward_result.scaled_reward[agent_next_idx])
            self.processing_buffer[agent_id]["{}_value_estimates".format(
                name)].append(values[name][agent_idx][0])

    def is_ready_update(self):
        """
        Returns whether or not the trainer has enough elements to run update model
        :return: A boolean corresponding to whether or not update_model() can be run
        """
        size_of_buffer = self.update_buffer.num_experiences
        return size_of_buffer > self.trainer_parameters["buffer_size"]

    def update_policy(self):
        """
        Uses demonstration_buffer to update the policy.
        The reward signal generators must be updated in this method at their own pace.
        """
        buffer_length = self.update_buffer.num_experiences
        self.trainer_metrics.start_policy_update_timer(
            number_experiences=buffer_length,
            mean_return=float(
                np.mean(self.cumulative_returns_since_policy_update)),
        )
        self.cumulative_returns_since_policy_update.clear()

        # Make sure batch_size is a multiple of sequence length. During training, we
        # will need to reshape the data into a batch_size x sequence_length tensor.
        batch_size = (self.trainer_parameters["batch_size"] -
                      self.trainer_parameters["batch_size"] %
                      self.policy.sequence_length)
        # Make sure there is at least one sequence
        batch_size = max(batch_size, self.policy.sequence_length)

        n_sequences = max(
            int(self.trainer_parameters["batch_size"] /
                self.policy.sequence_length), 1)

        advantages = self.update_buffer["advantages"].get_batch()
        self.update_buffer["advantages"].set(
            (advantages - advantages.mean()) / (advantages.std() + 1e-10))
        num_epoch = self.trainer_parameters["num_epoch"]
        batch_update_stats = defaultdict(list)
        for _ in range(num_epoch):
            self.update_buffer.shuffle(
                sequence_length=self.policy.sequence_length)
            buffer = self.update_buffer
            max_num_batch = buffer_length // batch_size
            for l in range(0, max_num_batch * batch_size, batch_size):
                update_stats = self.policy.update(
                    buffer.make_mini_batch(l, l + batch_size), n_sequences)
                for stat_name, value in update_stats.items():
                    batch_update_stats[stat_name].append(value)

        for stat, stat_list in batch_update_stats.items():
            self.stats[stat].append(np.mean(stat_list))

        if self.policy.bc_module:
            update_stats = self.policy.bc_module.update()
            for stat, val in update_stats.items():
                self.stats[stat].append(val)
        self.clear_update_buffer()
        self.trainer_metrics.end_policy_update()
예제 #21
0
class PPOTrainer(Trainer):
    """The PPOTrainer is an implementation of the PPO algorithm."""
    def __init__(self, brain, reward_buff_cap, trainer_parameters, training,
                 load, seed, run_id):
        """
        Responsible for collecting experiences and training PPO model.
        :param trainer_parameters: The parameters for the trainer (dictionary).
        :param training: Whether the trainer is set for training.
        :param load: Whether the model should be loaded.
        :param seed: The seed the model will be initialized with
        :param run_id: The identifier of the current run
        """
        super(PPOTrainer, self).__init__(brain, trainer_parameters, training,
                                         run_id)
        self.param_keys = [
            "batch_size",
            "beta",
            "buffer_size",
            "epsilon",
            "gamma",
            "hidden_units",
            "lambd",
            "learning_rate",
            "max_steps",
            "normalize",
            "num_epoch",
            "num_layers",
            "time_horizon",
            "sequence_length",
            "summary_freq",
            "use_recurrent",
            "summary_path",
            "memory_size",
            "use_curiosity",
            "curiosity_strength",
            "curiosity_enc_size",
            "model_path",
        ]

        self.check_param_keys()
        self.use_curiosity = bool(trainer_parameters["use_curiosity"])
        self.step = 0
        self.policy = PPOPolicy(seed, brain, trainer_parameters,
                                self.is_training, load)

        stats = {
            "Environment/Cumulative Reward": [],
            "Environment/Episode Length": [],
            "Policy/Value Estimate": [],
            "Policy/Entropy": [],
            "Losses/Value Loss": [],
            "Losses/Policy Loss": [],
            "Policy/Learning Rate": [],
        }
        if self.use_curiosity:
            stats["Losses/Forward Loss"] = []
            stats["Losses/Inverse Loss"] = []
            stats["Policy/Curiosity Reward"] = []
            self.intrinsic_rewards = {}
        self.stats = stats

        self.training_buffer = Buffer()
        self.cumulative_rewards = {}
        self._reward_buffer = deque(maxlen=reward_buff_cap)
        self.episode_steps = {}

    def __str__(self):
        return """Hyperparameters for the PPO Trainer of brain {0}: \n{1}""".format(
            self.brain_name,
            "\n".join([
                "\t{0}:\t{1}".format(x, self.trainer_parameters[x])
                for x in self.param_keys
            ]),
        )

    @property
    def parameters(self):
        """
        Returns the trainer parameters of the trainer.
        """
        return self.trainer_parameters

    @property
    def get_max_steps(self):
        """
        Returns the maximum number of steps. Is used to know when the trainer should be stopped.
        :return: The maximum number of steps of the trainer
        """
        return float(self.trainer_parameters["max_steps"])

    @property
    def get_step(self):
        """
        Returns the number of steps the trainer has performed
        :return: the step count of the trainer
        """
        return self.step

    @property
    def reward_buffer(self):
        """
        Returns the reward buffer. The reward buffer contains the cumulative
        rewards of the most recent episodes completed by agents using this
        trainer.
        :return: the reward buffer.
        """
        return self._reward_buffer

    def increment_step_and_update_last_reward(self):
        """
        Increment the step count of the trainer and Updates the last reward
        """
        if len(self.stats["Environment/Cumulative Reward"]) > 0:
            mean_reward = np.mean(self.stats["Environment/Cumulative Reward"])
            self.policy.update_reward(mean_reward)
        self.policy.increment_step()
        self.step = self.policy.get_current_step()

    def construct_curr_info(self, next_info: BrainInfo) -> BrainInfo:
        """
        Constructs a BrainInfo which contains the most recent previous experiences for all agents info
        which correspond to the agents in a provided next_info.
        :BrainInfo next_info: A t+1 BrainInfo.
        :return: curr_info: Reconstructed BrainInfo to match agents of next_info.
        """
        visual_observations = [[]]
        vector_observations = []
        text_observations = []
        memories = []
        rewards = []
        local_dones = []
        max_reacheds = []
        agents = []
        prev_vector_actions = []
        prev_text_actions = []
        action_masks = []
        for agent_id in next_info.agents:
            agent_brain_info = self.training_buffer[agent_id].last_brain_info
            if agent_brain_info is None:
                agent_brain_info = next_info
            agent_index = agent_brain_info.agents.index(agent_id)
            for i in range(len(next_info.visual_observations)):
                visual_observations[i].append(
                    agent_brain_info.visual_observations[i][agent_index])
            vector_observations.append(
                agent_brain_info.vector_observations[agent_index])
            text_observations.append(
                agent_brain_info.text_observations[agent_index])
            if self.policy.use_recurrent:
                if len(agent_brain_info.memories) > 0:
                    memories.append(agent_brain_info.memories[agent_index])
                else:
                    memories.append(self.policy.make_empty_memory(1))
            rewards.append(agent_brain_info.rewards[agent_index])
            local_dones.append(agent_brain_info.local_done[agent_index])
            max_reacheds.append(agent_brain_info.max_reached[agent_index])
            agents.append(agent_brain_info.agents[agent_index])
            prev_vector_actions.append(
                agent_brain_info.previous_vector_actions[agent_index])
            prev_text_actions.append(
                agent_brain_info.previous_text_actions[agent_index])
            action_masks.append(agent_brain_info.action_masks[agent_index])
        if self.policy.use_recurrent:
            memories = np.vstack(memories)
        curr_info = BrainInfo(
            visual_observations,
            vector_observations,
            text_observations,
            memories,
            rewards,
            agents,
            local_dones,
            prev_vector_actions,
            prev_text_actions,
            max_reacheds,
            action_masks,
        )
        return curr_info

    def add_experiences(
        self,
        curr_all_info: AllBrainInfo,
        next_all_info: AllBrainInfo,
        take_action_outputs,
    ):
        """
        Adds experiences to each agent's experience history.
        :param curr_all_info: Dictionary of all current brains and corresponding BrainInfo.
        :param next_all_info: Dictionary of all current brains and corresponding BrainInfo.
        :param take_action_outputs: The outputs of the Policy's get_action method.
        """
        self.trainer_metrics.start_experience_collection_timer()
        if take_action_outputs:
            self.stats["Policy/Value Estimate"].append(
                take_action_outputs["value"].mean())
            self.stats["Policy/Entropy"].append(
                take_action_outputs["entropy"].mean())
            self.stats["Policy/Learning Rate"].append(
                take_action_outputs["learning_rate"])

        curr_info = curr_all_info[self.brain_name]
        next_info = next_all_info[self.brain_name]

        for agent_id in curr_info.agents:
            self.training_buffer[agent_id].last_brain_info = curr_info
            self.training_buffer[
                agent_id].last_take_action_outputs = take_action_outputs

        if curr_info.agents != next_info.agents:
            curr_to_use = self.construct_curr_info(next_info)
        else:
            curr_to_use = curr_info

        intrinsic_rewards = self.policy.get_intrinsic_rewards(
            curr_to_use, next_info)

        for agent_id in next_info.agents:
            stored_info = self.training_buffer[agent_id].last_brain_info
            stored_take_action_outputs = self.training_buffer[
                agent_id].last_take_action_outputs
            if stored_info is not None:
                idx = stored_info.agents.index(agent_id)
                next_idx = next_info.agents.index(agent_id)
                if not stored_info.local_done[idx]:
                    for i, _ in enumerate(stored_info.visual_observations):
                        self.training_buffer[agent_id][
                            "visual_obs%d" % i].append(
                                stored_info.visual_observations[i][idx])
                        self.training_buffer[agent_id][
                            "next_visual_obs%d" % i].append(
                                next_info.visual_observations[i][next_idx])
                    if self.policy.use_vec_obs:
                        self.training_buffer[agent_id]["vector_obs"].append(
                            stored_info.vector_observations[idx])
                        self.training_buffer[agent_id][
                            "next_vector_in"].append(
                                next_info.vector_observations[next_idx])
                    if self.policy.use_recurrent:
                        if stored_info.memories.shape[1] == 0:
                            stored_info.memories = np.zeros(
                                (len(stored_info.agents), self.policy.m_size))
                        self.training_buffer[agent_id]["memory"].append(
                            stored_info.memories[idx])
                    actions = stored_take_action_outputs["action"]
                    if self.policy.use_continuous_act:
                        actions_pre = stored_take_action_outputs["pre_action"]
                        self.training_buffer[agent_id]["actions_pre"].append(
                            actions_pre[idx])
                        epsilons = stored_take_action_outputs[
                            "random_normal_epsilon"]
                        self.training_buffer[agent_id][
                            "random_normal_epsilon"].append(epsilons[idx])
                    else:
                        self.training_buffer[agent_id]["action_mask"].append(
                            stored_info.action_masks[idx], padding_value=1)
                    a_dist = stored_take_action_outputs["log_probs"]
                    value = stored_take_action_outputs["value"]
                    self.training_buffer[agent_id]["actions"].append(
                        actions[idx])
                    self.training_buffer[agent_id]["prev_action"].append(
                        stored_info.previous_vector_actions[idx])
                    self.training_buffer[agent_id]["masks"].append(1.0)
                    if self.use_curiosity:
                        self.training_buffer[agent_id]["rewards"].append(
                            next_info.rewards[next_idx] +
                            intrinsic_rewards[next_idx])
                    else:
                        self.training_buffer[agent_id]["rewards"].append(
                            next_info.rewards[next_idx])
                    self.training_buffer[agent_id]["action_probs"].append(
                        a_dist[idx])
                    self.training_buffer[agent_id]["value_estimates"].append(
                        value[idx][0])
                    if agent_id not in self.cumulative_rewards:
                        self.cumulative_rewards[agent_id] = 0
                    self.cumulative_rewards[agent_id] += next_info.rewards[
                        next_idx]
                    if self.use_curiosity:
                        if agent_id not in self.intrinsic_rewards:
                            self.intrinsic_rewards[agent_id] = 0
                        self.intrinsic_rewards[agent_id] += intrinsic_rewards[
                            next_idx]
                if not next_info.local_done[next_idx]:
                    if agent_id not in self.episode_steps:
                        self.episode_steps[agent_id] = 0
                    self.episode_steps[agent_id] += 1
        self.trainer_metrics.end_experience_collection_timer()

    def process_experiences(self, current_info: AllBrainInfo,
                            new_info: AllBrainInfo):
        """
        Checks agent histories for processing condition, and processes them as necessary.
        Processing involves calculating value and advantage targets for model updating step.
        :param current_info: Dictionary of all current brains and corresponding BrainInfo.
        :param new_info: Dictionary of all next brains and corresponding BrainInfo.
        """
        self.trainer_metrics.start_experience_collection_timer()
        info = new_info[self.brain_name]
        for l in range(len(info.agents)):
            agent_actions = self.training_buffer[info.agents[l]]["actions"]
            if (info.local_done[l] or len(agent_actions) >
                    self.trainer_parameters["time_horizon"]
                ) and len(agent_actions) > 0:
                agent_id = info.agents[l]
                if info.local_done[l] and not info.max_reached[l]:
                    value_next = 0.0
                else:
                    if info.max_reached[l]:
                        bootstrapping_info = self.training_buffer[
                            agent_id].last_brain_info
                        idx = bootstrapping_info.agents.index(agent_id)
                    else:
                        bootstrapping_info = info
                        idx = l
                    value_next = self.policy.get_value_estimate(
                        bootstrapping_info, idx)

                self.training_buffer[agent_id]["advantages"].set(
                    get_gae(
                        rewards=self.training_buffer[agent_id]
                        ["rewards"].get_batch(),
                        value_estimates=self.training_buffer[agent_id]
                        ["value_estimates"].get_batch(),
                        value_next=value_next,
                        gamma=self.trainer_parameters["gamma"],
                        lambd=self.trainer_parameters["lambd"],
                    ))
                self.training_buffer[agent_id]["discounted_returns"].set(
                    self.training_buffer[agent_id]["advantages"].get_batch() +
                    self.training_buffer[agent_id]
                    ["value_estimates"].get_batch())

                self.training_buffer.append_update_buffer(
                    agent_id,
                    batch_size=None,
                    training_length=self.policy.sequence_length,
                )

                self.training_buffer[agent_id].reset_agent()
                if info.local_done[l]:
                    self.cumulative_returns_since_policy_update.append(
                        self.cumulative_rewards.get(agent_id, 0))
                    self.stats["Environment/Cumulative Reward"].append(
                        self.cumulative_rewards.get(agent_id, 0))
                    self.reward_buffer.appendleft(
                        self.cumulative_rewards.get(agent_id, 0))
                    self.stats["Environment/Episode Length"].append(
                        self.episode_steps.get(agent_id, 0))
                    self.cumulative_rewards[agent_id] = 0
                    self.episode_steps[agent_id] = 0
                    if self.use_curiosity:
                        self.stats["Policy/Curiosity Reward"].append(
                            self.intrinsic_rewards.get(agent_id, 0))
                        self.intrinsic_rewards[agent_id] = 0
        self.trainer_metrics.end_experience_collection_timer()

    def end_episode(self):
        """
        A signal that the Episode has ended. The buffer must be reset.
        Get only called when the academy resets.
        """
        self.training_buffer.reset_local_buffers()
        for agent_id in self.cumulative_rewards:
            self.cumulative_rewards[agent_id] = 0
        for agent_id in self.episode_steps:
            self.episode_steps[agent_id] = 0
        if self.use_curiosity:
            for agent_id in self.intrinsic_rewards:
                self.intrinsic_rewards[agent_id] = 0

    def is_ready_update(self):
        """
        Returns whether or not the trainer has enough elements to run update model
        :return: A boolean corresponding to whether or not update_model() can be run
        """
        size_of_buffer = len(self.training_buffer.update_buffer["actions"])
        return size_of_buffer > max(
            int(self.trainer_parameters["buffer_size"] /
                self.policy.sequence_length), 1)

    def update_policy(self):
        """
        Uses demonstration_buffer to update the policy.
        """
        self.trainer_metrics.start_policy_update_timer(
            number_experiences=len(
                self.training_buffer.update_buffer["actions"]),
            mean_return=float(
                np.mean(self.cumulative_returns_since_policy_update)),
        )
        self.cumulative_returns_since_policy_update = []
        n_sequences = max(
            int(self.trainer_parameters["batch_size"] /
                self.policy.sequence_length), 1)
        value_total, policy_total, forward_total, inverse_total = [], [], [], []
        advantages = self.training_buffer.update_buffer[
            "advantages"].get_batch()
        self.training_buffer.update_buffer["advantages"].set(
            (advantages - advantages.mean()) / (advantages.std() + 1e-10))
        num_epoch = self.trainer_parameters["num_epoch"]
        for _ in range(num_epoch):
            self.training_buffer.update_buffer.shuffle()
            buffer = self.training_buffer.update_buffer
            for l in range(
                    len(self.training_buffer.update_buffer["actions"]) //
                    n_sequences):
                start = l * n_sequences
                end = (l + 1) * n_sequences
                run_out = self.policy.update(
                    buffer.make_mini_batch(start, end), n_sequences)
                value_total.append(run_out["value_loss"])
                policy_total.append(np.abs(run_out["policy_loss"]))
                if self.use_curiosity:
                    inverse_total.append(run_out["inverse_loss"])
                    forward_total.append(run_out["forward_loss"])
        self.stats["Losses/Value Loss"].append(np.mean(value_total))
        self.stats["Losses/Policy Loss"].append(np.mean(policy_total))
        if self.use_curiosity:
            self.stats["Losses/Forward Loss"].append(np.mean(forward_total))
            self.stats["Losses/Inverse Loss"].append(np.mean(inverse_total))
        self.training_buffer.reset_update_buffer()
        self.trainer_metrics.end_policy_update()