import os import tempfile import tensorflow as tf import zipfile import cloudpickle import numpy as np import baselines.common.tf_util as U from baselines.common.tf_util import load_variables, save_variables from baselines import logger from baselines.common.schedules import LinearSchedule from baselines.common import set_global_seeds from baselines import deepq from baselines.deepq.replay_buffer import ReplayBuffer, PrioritizedReplayBuffer from baselines.deepq.utils import ObservationInput from baselines.common.tf_util import get_session from baselines.deepq.models import build_q_func class ActWrapper(object): def __init__(self, act, act_params): self._act = act self._act_params = act_params self.initial_state = None @staticmethod def load_act(path): with open(path, "rb") as f: model_data, act_params = cloudpickle.load(f) act = deepq.build_act(**act_params) sess = tf.compat.v1.Session() sess.__enter__() with tempfile.TemporaryDirectory() as td: arc_path = os.path.join(td, "packed.zip") with open(arc_path, "wb") as f: f.write(model_data) zipfile.ZipFile(arc_path, 'r', zipfile.ZIP_DEFLATED).extractall(td) load_variables(os.path.join(td, "model")) return ActWrapper(act, act_params) def __call__(self, *args, **kwargs): return self._act(*args, **kwargs) def step(self, observation, **kwargs): # DQN doesn't use RNNs so we ignore states and masks kwargs.pop('S', None) kwargs.pop('M', None) return self._act([observation], **kwargs), None, None, None def save_act(self, path=None): """Save model to a pickle located at `path`""" if path is None: path = os.path.join(logger.get_dir(), "model.pkl") with tempfile.TemporaryDirectory() as td: save_variables(os.path.join(td, "model")) arc_name = os.path.join(td, "packed.zip") with zipfile.ZipFile(arc_name, 'w') as zipf: for root, dirs, files in os.walk(td): for fname in files: file_path = os.path.join(root, fname) if file_path != arc_name: zipf.write(file_path, os.path.relpath(file_path, td)) with open(arc_name, "rb") as f: model_data = f.read() with open(path, "wb") as f: cloudpickle.dump((model_data, self._act_params), f) def save(self, path): save_variables(path) def load_act(path): """Load act function that was returned by learn function. Parameters ---------- path: str path to the act function pickle Returns ------- act: ActWrapper function that takes a batch of observations and returns actions. """ return ActWrapper.load_act(path) def learn(env, network, seed=None, lr=5e-4, total_timesteps=100000, buffer_size=50000, exploration_fraction=0.1, exploration_final_eps=0.02, train_freq=1, batch_size=32, print_freq=100, checkpoint_freq=10000, checkpoint_path=None, learning_starts=1000, gamma=1.0, target_network_update_freq=500, prioritized_replay=False, prioritized_replay_alpha=0.6, prioritized_replay_beta0=0.4, prioritized_replay_beta_iters=None, prioritized_replay_eps=1e-6, param_noise=False, callback=None, load_path=None, **network_kwargs ): """Train a deepq model. Parameters ------- env: gym.Env environment to train on network: string or a function neural network to use as a q function approximator. If string, has to be one of the names of registered models in baselines.common.models (mlp, cnn, conv_only). If a function, should take an observation tensor and return a latent variable tensor, which will be mapped to the Q function heads (see build_q_func in baselines.deepq.models for details on that) seed: int or None prng seed. The runs with the same seed "should" give the same results. If None, no seeding is used. lr: float learning rate for adam optimizer total_timesteps: int number of env steps to optimizer for buffer_size: int size of the replay buffer exploration_fraction: float fraction of entire training period over which the exploration rate is annealed exploration_final_eps: float final value of random action probability train_freq: int update the model every `train_freq` steps. batch_size: int size of a batch sampled from replay buffer for training print_freq: int how often to print out training progress set to None to disable printing checkpoint_freq: int how often to save the model. This is so that the best version is restored at the end of the training. If you do not wish to restore the best version at the end of the training set this variable to None. learning_starts: int how many steps of the model to collect transitions for before learning starts gamma: float discount factor target_network_update_freq: int update the target network every `target_network_update_freq` steps. prioritized_replay: True if True prioritized replay buffer will be used. prioritized_replay_alpha: float alpha parameter for prioritized replay buffer prioritized_replay_beta0: float initial value of beta for prioritized replay buffer prioritized_replay_beta_iters: int number of iterations over which beta will be annealed from initial value to 1.0. If set to None equals to total_timesteps. prioritized_replay_eps: float epsilon to add to the TD errors when updating priorities. param_noise: bool whether or not to use parameter space noise (https://arxiv.org/abs/1706.01905) callback: (locals, globals) -> None function called at every steps with state of the algorithm. If callback returns true training stops. load_path: str path to load the model from. (default: None) **network_kwargs additional keyword arguments to pass to the network builder. Returns ------- act: ActWrapper Wrapper over act function. Adds ability to save it and load it. See header of baselines/deepq/categorical.py for details on the act function. """ # Create all the functions necessary to train the model sess = get_session() set_global_seeds(seed) q_func = build_q_func(network, **network_kwargs) # capture the shape outside the closure so that the env object is not serialized # by cloudpickle when serializing make_obs_ph observation_space = env.observation_space def make_obs_ph(name): return ObservationInput(observation_space, name=name) act, train, update_target, debug = deepq.build_train( make_obs_ph=make_obs_ph, q_func=q_func, num_actions=env.action_space.n, optimizer=tf.compat.v1.train.AdamOptimizer(learning_rate=lr), gamma=gamma, grad_norm_clipping=10, param_noise=param_noise ) act_params = { 'make_obs_ph': make_obs_ph, 'q_func': q_func, 'num_actions': env.action_space.n, } act = ActWrapper(act, act_params) # Create the replay buffer if prioritized_replay: replay_buffer = PrioritizedReplayBuffer(buffer_size, alpha=prioritized_replay_alpha) if prioritized_replay_beta_iters is None: prioritized_replay_beta_iters = total_timesteps beta_schedule = LinearSchedule(prioritized_replay_beta_iters, initial_p=prioritized_replay_beta0, final_p=1.0) else: replay_buffer = ReplayBuffer(buffer_size) beta_schedule = None # Create the schedule for exploration starting from 1. exploration = LinearSchedule(schedule_timesteps=int(exploration_fraction * total_timesteps), initial_p=1.0, final_p=exploration_final_eps) # Initialize the parameters and copy them to the target network. U.initialize() update_target() episode_rewards = [0.0] saved_mean_reward = None obs = env.reset() reset = True with tempfile.TemporaryDirectory() as td: td = checkpoint_path or td model_file = os.path.join(td, "model") model_saved = False if tf.train.latest_checkpoint(td) is not None: load_variables(model_file) logger.log('Loaded model from {}'.format(model_file)) model_saved = True elif load_path is not None: load_variables(load_path) logger.log('Loaded model from {}'.format(load_path)) for t in range(total_timesteps): if callback is not None: if callback(locals(), globals()): break # Take action and update exploration to the newest value kwargs = {} if not param_noise: update_eps = exploration.value(t) update_param_noise_threshold = 0. else: update_eps = 0. # Compute the threshold such that the KL divergence between perturbed and non-perturbed # policy is comparable to eps-greedy exploration with eps = exploration.value(t). # See Appendix C.1 in Parameter Space Noise for Exploration, Plappert et al., 2017 # for detailed explanation. update_param_noise_threshold = -np.log(1. - exploration.value(t) + exploration.value(t) / float(env.action_space.n)) kwargs['reset'] = reset kwargs['update_param_noise_threshold'] = update_param_noise_threshold kwargs['update_param_noise_scale'] = True action = act(np.array(obs)[None], update_eps=update_eps, **kwargs)[0] env_action = action reset = False new_obs, rew, done, _ = env.step(env_action) # Store transition in the replay buffer. replay_buffer.add(obs, action, rew, new_obs, float(done)) obs = new_obs episode_rewards[-1] += rew if done: obs = env.reset() episode_rewards.append(0.0) reset = True if t > learning_starts and t % train_freq == 0: # Minimize the error in Bellman's equation on a batch sampled from replay buffer. if prioritized_replay: experience = replay_buffer.sample(batch_size, beta=beta_schedule.value(t)) (obses_t, actions, rewards, obses_tp1, dones, weights, batch_idxes) = experience else: obses_t, actions, rewards, obses_tp1, dones = replay_buffer.sample(batch_size) weights, batch_idxes = np.ones_like(rewards), None td_errors = train(obses_t, actions, rewards, obses_tp1, dones, weights) if prioritized_replay: new_priorities = np.abs(td_errors) + prioritized_replay_eps replay_buffer.update_priorities(batch_idxes, new_priorities) if t > learning_starts and t % target_network_update_freq == 0: # Update target network periodically. update_target() mean_100ep_reward = round(np.mean(episode_rewards[-101:-1]), 1) num_episodes = len(episode_rewards) if done and print_freq is not None and len(episode_rewards) % print_freq == 0: logger.record_tabular("steps", t) logger.record_tabular("episodes", num_episodes) logger.record_tabular("mean 100 episode reward", mean_100ep_reward) logger.record_tabular("% time spent exploring", int(100 * exploration.value(t))) logger.dump_tabular() if (checkpoint_freq is not None and t > learning_starts and num_episodes > 100 and t % checkpoint_freq == 0): if saved_mean_reward is None or mean_100ep_reward > saved_mean_reward: if print_freq is not None: logger.log("Saving model due to mean reward increase: {} -> {}".format( saved_mean_reward, mean_100ep_reward)) save_variables(model_file) model_saved = True saved_mean_reward = mean_100ep_reward if model_saved: if print_freq is not None: logger.log("Restored model with mean reward: {}".format(saved_mean_reward)) load_variables(model_file) return act