Exemple #1
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def denormalize(x, stats):
    if stats is None:
        return x
    state_mean = stats.mean()
    state_std = stats.std()
    state_mean = np.array(state_mean, dtype=np.float32) if not isinstance(state_mean, np.ndarray) else state_mean.astype(np.float32)
    state_std = np.array(state_std, dtype=np.float32) if not isinstance(state_std, np.ndarray) else state_std.astype(np.float32)
    return x * torch_utils.toTensor(state_std) + torch_utils.toTensor(state_mean)
Exemple #2
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    def run(self):
        # Here, we init the lists that will contain the mb of experiences
        mb_obs, mb_rewards, mb_actions, mb_values, mb_dones, mb_neglogpacs = [],[],[],[],[],[]
        mb_states = self.states
        epinfos = []
        # For n in range number of steps
        for _ in range(self.nsteps):
            # Given observations, get action value and neglopacs
            # We already have self.obs because Runner superclass run self.obs[:] = env.reset() on init
            outputs = self.model.step(torch_utils.toTensor(self.obs).float(),
                                      S=self.states,
                                      M=self.dones)
            actions, values, self.states, neglogpacs = torch_utils.toNumpy(
                outputs)
            mb_obs.append(self.obs.copy())
            mb_actions.append(actions)
            mb_values.append(values)
            mb_neglogpacs.append(neglogpacs)
            mb_dones.append(self.dones)

            # Take actions in env and look the results
            # Infos contains a ton of useful informations
            self.obs[:], rewards, self.dones, infos = self.env.step(actions)
            for info in infos:
                maybeepinfo = info.get('episode')
                if maybeepinfo: epinfos.append(maybeepinfo)
            mb_rewards.append(rewards)
        #batch of steps to batch of rollouts
        mb_obs = np.asarray(mb_obs, dtype=self.obs.dtype)
        mb_rewards = np.asarray(mb_rewards, dtype=np.float32)
        mb_actions = np.asarray(mb_actions)
        mb_values = np.asarray(mb_values, dtype=np.float32)
        mb_neglogpacs = np.asarray(mb_neglogpacs, dtype=np.float32)
        mb_dones = np.asarray(mb_dones, dtype=np.bool)
        last_values = self.model.value(torch_utils.toTensor(self.obs).float(),
                                       S=self.states,
                                       M=self.dones)
        last_values = torch_utils.toNumpy(last_values)

        # discount/bootstrap off value fn
        mb_returns = np.zeros_like(mb_rewards)
        mb_advs = np.zeros_like(mb_rewards)
        lastgaelam = 0
        for t in reversed(range(self.nsteps)):
            if t == self.nsteps - 1:
                nextnonterminal = 1.0 - self.dones
                nextvalues = last_values
            else:
                nextnonterminal = 1.0 - mb_dones[t + 1]
                nextvalues = mb_values[t + 1]
            delta = mb_rewards[
                t] + self.gamma * nextvalues * nextnonterminal - mb_values[t]
            mb_advs[
                t] = lastgaelam = delta + self.gamma * self.lam * nextnonterminal * lastgaelam
        mb_returns = mb_advs + mb_values
        return (*map(sf01, (mb_obs, mb_returns, mb_dones, mb_actions,
                            mb_values, mb_neglogpacs)), mb_states, epinfos)
Exemple #3
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def main(args):
    # configure logger, disable logging in child MPI processes (with rank > 0)

    arg_parser = common_arg_parser()
    args, unknown_args = arg_parser.parse_known_args(args)
    extra_args = parse_cmdline_kwargs(unknown_args)
    torch_utils.device = args.device

    if MPI is None or MPI.COMM_WORLD.Get_rank() == 0:
        rank = 0
        configure_logger(args.log_path,
                         viz_server=args.viz_server,
                         viz_port=args.viz_port)
    else:
        rank = MPI.COMM_WORLD.Get_rank()
        configure_logger(args.log_path,
                         format_strs=[],
                         viz_server=args.viz_server,
                         viz_port=args.viz_port)

    model, env = train(args, extra_args)

    if args.save_path is not None and rank == 0:
        os.makedirs(osp.expanduser(args.save_path), exist_ok=True)
        save_path = osp.join(osp.expanduser(args.save_path), 'model.pth')
        model.save(save_path)

    if args.play:
        logger.log("Running trained model")
        from ptbaselines.algos.common.torch_utils import toNumpy, toTensor
        obs = env.reset()

        state = None
        dones = np.zeros((1, ))

        episode_rew = np.zeros(env.num_envs) if isinstance(
            env, VecEnv) else np.zeros(1)
        while True:
            if state is not None:
                actions, _, state, _ = toNumpy(
                    model.step(toTensor(obs).float(), S=state, M=dones))
            else:
                actions, _, _, _ = toNumpy(model.step(toTensor(obs).float()))

            obs, rew, done, _ = env.step(actions)
            # print('rewards: {}'.format(rew))
            episode_rew += rew
            env.render()
            done_any = done.any() if isinstance(done, np.ndarray) else done
            if done_any:
                for i in np.nonzero(done)[0]:
                    print('episode_rew={}'.format(episode_rew[i]))
                    episode_rew[i] = 0

    env.close()

    return model
Exemple #4
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    def adapt_param_noise(self):
        try:
            from mpi4py import MPI
        except ImportError:
            MPI = None

        if self.param_noise is None:
            return 0.

        # Perturb a separate copy of the policy to adjust the scale for the next "real" perturbation.
        batch = self.memory.sample(batch_size=self.batch_size)
        obs0 = torch_utils.toTensor(batch['obs0']).float()
        normalize_obs0 = self.normalize_obs(obs0)
        self.perturb_params(self.actor, self.adaptive_actor, self.param_noise.current_stddev)
        with torch.no_grad():
            actions = self.actor(normalize_obs0)
            adaptive_actions = self.adaptive_actor(normalize_obs0)
            distance = torch.sqrt(torch.pow(actions - adaptive_actions, 2.0).mean())

        if MPI is not None:
            mean_distance = MPI.COMM_WORLD.allreduce(distance, op=MPI.SUM) / MPI.COMM_WORLD.Get_size()
        else:
            mean_distance = distance

        self.param_noise.adapt(mean_distance.data.cpu().item())
        return mean_distance
Exemple #5
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    def train(self):
        # Get a batch.
        batch = self.memory.sample(batch_size=self.batch_size)
        obs0 = torch_utils.toTensor(batch['obs0'])
        obs1 = torch_utils.toTensor(batch['obs1'])
        rewards = torch_utils.toTensor(batch['rewards'])
        terminals1= torch_utils.toTensor(batch['terminals1'].astype('float32'))
        actions = torch_utils.toTensor(batch['actions'])
        
        normalize_obs0 = self.normalize_obs(obs0)
        normalize_obs1 = self.normalize_obs(obs1)

        # compute target
        Q_obs1 = denormalize(self.target_critic(normalize_obs1, self.target_actor(normalize_obs1)), self.ret_rms)
        target_Q = rewards + (1. - terminals1) * self.gamma * Q_obs1
        critic_target = torch.clamp(normalize(target_Q, self.ret_rms), self.return_range[0], self.return_range[1]).detach()

        if self.normalize_returns and self.enable_popart:
            old_mean = self.ret_rms.mean()
            old_std = self.ret_rms.std()
            self.ret_rms.update(torch_utils.toNumpy(target_Q.view(-1)))
            self.popart(old_mean, old_std)

        # compute critic loss
        Q_obs0 = self.critic(normalize_obs0, actions)
        critic_loss = F.mse_loss(Q_obs0, critic_target)

        # update critic
        self.critic_optimizer.zero_grad()
        critic_loss.backward()
        mpi_util.average_gradients(self.critic_optimizer.param_groups)
        self.critic_optimizer.step()

        # compute actor loss
        actor_actions = self.actor(normalize_obs0)
        critic_with_actor = denormalize(torch.clamp(self.critic(normalize_obs0, actor_actions), self.return_range[0], self.return_range[1]), self.ret_rms)
        actor_loss = -critic_with_actor.mean()

        # update actor
        self.actor_optimizer.zero_grad()
        actor_loss.backward()
        mpi_util.average_gradients(self.actor_optimizer.param_groups)
        self.actor_optimizer.step()

        return critic_loss.data.cpu().item(), actor_loss.data.cpu().item()
Exemple #6
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    def step(self, obs, apply_noise=True, compute_Q=True):
        if isinstance(obs, np.ndarray):
            obs = torch_utils.toTensor(obs).float()
        norm_obs = self.normalize_obs(obs)
        if self.param_noise is not None and apply_noise:
            action = self.pertubed_actor(norm_obs)
        else:
            action = self.actor(norm_obs)
        if compute_Q:
            normalize_value = self.critic(norm_obs, action)
            q = denormalize(torch.clamp(normalize_value, self.return_range[0], self.return_range[1]), self.ret_rms)
        else:
            q = None

        if self.action_noise is not None and apply_noise:
            noise = self.action_noise()
            assert noise.shape == action[0].shape
            action += torch_utils.toTensor(noise[np.newaxis]).float()
        action = torch.clamp(action, self.action_range[0], self.action_range[1])

        return torch_utils.toNumpy(action), q.data.cpu().item(), None, None
def main():
    env = gym.make("CartPole-v0")
    act = deepq.learn(env,
                      network='mlp',
                      total_timesteps=0,
                      load_path="cartpole_model.pth")

    while True:
        obs, done = env.reset(), False
        episode_rew = 0
        while not done:
            env.render()
            action = act.actions(torch_utils.toTensor(obs[None]).float(),
                                 stochastic=False)[0].item()
            obs, rew, done, _ = env.step(action)
            episode_rew += rew
        print("Episode reward", episode_rew)
Exemple #8
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def main():
    env = gym.make("MountainCar-v0")
    act = deepq.learn(env,
                      network=models.mlp(env.observation_space.shape,
                                         num_layers=1,
                                         num_hidden=64),
                      total_timesteps=0,
                      load_path='mountaincar_model.pth')

    while True:
        obs, done = env.reset(), False
        episode_rew = 0
        while not done:
            env.render()
            action = act.actions(torch_utils.toTensor(obs[None]).float(),
                                 stochastic=False)[0].item()
            obs, rew, done, _ = env.step(action)
            episode_rew += rew
        print("Episode reward", episode_rew)
Exemple #9
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def main():
    env = make_atari("PongNoFrameskip-v4")
    env = deepq.wrap_atari_dqn(env)
    act = deepq.learn(env,
                      "conv_only",
                      convs=[(32, 8, 4), (64, 4, 2), (64, 3, 1)],
                      hiddens=[256],
                      dueling=True,
                      total_timesteps=0,
                      load_path='pong_model.pth')

    while True:
        obs, done = env.reset(), False
        episode_rew = 0
        while not done:
            env.render()
            action = act.actions(torch_utils.toTensor(obs[None]).float(),
                                 stochastic=False)[0].item()
            obs, rew, done, _ = env.step(action)
            episode_rew += rew
        print("Episode reward", episode_rew)
Exemple #10
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def learn(network,
          env,
          seed=None,
          nsteps=5,
          total_timesteps=int(80e6),
          vf_coef=0.5,
          ent_coef=0.01,
          max_grad_norm=0.5,
          lr=7e-4,
          lrschedule='linear',
          epsilon=1e-5,
          alpha=0.99,
          gamma=0.99,
          log_interval=100,
          load_path=None,
          **network_kwargs):
    '''
    Main entrypoint for A2C algorithm. Train a policy with given network architecture on a given environment using a2c algorithm.
    Parameters:
    -----------
    network:            policy network architecture. Either string (mlp, lstm, lnlstm, cnn_lstm, cnn, cnn_small, conv_only - see baselines.common/models.py for full list)
                        specifying the standard network architecture, or a function that takes tensorflow tensor as input and returns
                        tuple (output_tensor, extra_feed) where output tensor is the last network layer output, extra_feed is None for feed-forward
                        neural nets, and extra_feed is a dictionary describing how to feed state into the network for recurrent neural nets.
                        See baselines.common/policies.py/lstm for more details on using recurrent nets in policies
    env:                RL environment. Should implement interface similar to VecEnv (baselines.common/vec_env) or be wrapped with DummyVecEnv (baselines.common/vec_env/dummy_vec_env.py)
    seed:               seed to make random number sequence in the alorightm reproducible. By default is None which means seed from system noise generator (not reproducible)
    nsteps:             int, number of steps of the vectorized environment per update (i.e. batch size is nsteps * nenv where
                        nenv is number of environment copies simulated in parallel)
    total_timesteps:    int, total number of timesteps to train on (default: 80M)
    vf_coef:            float, coefficient in front of value function loss in the total loss function (default: 0.5)
    ent_coef:           float, coeffictiant in front of the policy entropy in the total loss function (default: 0.01)
    max_gradient_norm:  float, gradient is clipped to have global L2 norm no more than this value (default: 0.5)
    lr:                 float, learning rate for RMSProp (current implementation has RMSProp hardcoded in) (default: 7e-4)
    lrschedule:         schedule of learning rate. Can be 'linear', 'constant', or a function [0..1] -> [0..1] that takes fraction of the training progress as input and
                        returns fraction of the learning rate (specified as lr) as output
    epsilon:            float, RMSProp epsilon (stabilizes square root computation in denominator of RMSProp update) (default: 1e-5)
    alpha:              float, RMSProp decay parameter (default: 0.99)
    gamma:              float, reward discounting parameter (default: 0.99)
    log_interval:       int, specifies how frequently the logs are printed out (default: 100)
    **network_kwargs:   keyword arguments to the policy / network builder. See baselines.common/policies.py/build_policy and arguments to a particular type of network
                        For instance, 'mlp' network architecture has arguments num_hidden and num_layers.
    '''

    set_global_seeds(seed)

    # Get the nb of env
    nenvs = env.num_envs
    policy = build_policy(env, network, **network_kwargs)

    # Instantiate the model object (that creates step_model and train_model)
    model = Model(policy=policy,
                  env=env,
                  nsteps=nsteps,
                  ent_coef=ent_coef,
                  vf_coef=vf_coef,
                  max_grad_norm=max_grad_norm,
                  lr=lr,
                  alpha=alpha,
                  epsilon=epsilon,
                  total_timesteps=total_timesteps,
                  lrschedule=lrschedule)
    if load_path is not None:
        model.load(load_path)

    # Instantiate the runner object
    runner = Runner(env, model, nsteps=nsteps, gamma=gamma)
    epinfobuf = deque(maxlen=100)

    # Calculate the batch_size
    nbatch = nenvs * nsteps

    # Start total timer
    tstart = time.time()

    for update in range(1, total_timesteps // nbatch + 1):
        # Get mini batch of experiences
        obs, states, rewards, masks, actions, values, epinfos = runner.run()
        obs, rewards, masks, actions, values = torch_utils.toTensor(
            (obs, rewards, masks, actions, values))
        epinfobuf.extend(epinfos)

        model_outputs = model.train(obs, states, rewards, masks, actions,
                                    values)
        policy_loss, value_loss, policy_entropy = torch_utils.toNumpy(
            model_outputs)
        nseconds = time.time() - tstart

        # Calculate the fps (frame per second)
        fps = int((update * nbatch) / nseconds)
        if update % log_interval == 0 or update == 1:
            # Calculates if value function is a good predicator of the returns (ev > 1)
            # or if it's just worse than predicting nothing (ev =< 0)
            ev = explained_variance(*torch_utils.toNumpy((values, rewards)))
            logger.record_tabular("nupdates", update)
            logger.record_tabular("total_timesteps", update * nbatch)
            logger.record_tabular("fps", fps)
            logger.record_tabular("policy_entropy", float(policy_entropy))
            logger.record_tabular("value_loss", float(value_loss))
            logger.record_tabular("explained_variance", float(ev))
            logger.record_tabular(
                "eprewmean", safemean([epinfo['r'] for epinfo in epinfobuf]))
            logger.record_tabular(
                "eplenmean", safemean([epinfo['l'] for epinfo in epinfobuf]))
            logger.dump_tabular()

            # plot using visdom
            timesteps = update * nbatch
            logger.vizkv('eprewmean', timesteps,
                         safemean([epinfo['r'] for epinfo in epinfobuf]))
            logger.vizkv('eplenmean', timesteps,
                         safemean([epinfo['l'] for epinfo in epinfobuf]))
            logger.vizkv('policy_loss', timesteps, policy_loss)
            logger.vizkv('value_loss', timesteps, value_loss)
            logger.vizkv('policy_entropy', timesteps, policy_entropy)

    return model
Exemple #11
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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
    set_global_seeds(seed)

    if checkpoint_path is not None:
        save_path = osp.join(checkpoint_path, 'model.pth')
    else:
        checkdir = osp.join(logger.get_dir(), 'checkpoints')
        os.makedirs(checkdir, exist_ok=True)
        save_path = osp.join(checkdir, 'model.pth')

    q_net = QNet(env, network, **network_kwargs)
    model = Model(qnet=q_net,
                  lr=lr,
                  grad_norm_clipping=10,
                  gamma=gamma,
                  param_noise=param_noise)

    model_saved = False
    if load_path is not None:
        logger.log('Loaded model from {}'.format(load_path))
        model.load(load_path)
        # model_save = True

    # 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)

    episode_rewards = [0.0]
    saved_mean_reward = None
    obs = env.reset()
    reset = True

    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
        if not param_noise:
            update_eps = exploration.value(t)
            update_param_noise_threshold = 0.
            action = model.actions(torch_utils.toTensor(
                np.array(obs, dtype=np.float32)[None]),
                                   eps=update_eps)
        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))
            model.update_noise_scale(
                torch_utils.toTensor(np.array(obs, dtype=np.float32)[None]),
                update_param_noise_threshold)
            action = model.actions_with_param_noise(torch_utils.toTensor(
                np.array(obs, dtype=np.float32)[None]),
                                                    eps=update_eps,
                                                    reset=reset)
        action = torch_utils.toNumpy(action)[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, debug = model.train(
                *torch_utils.toTensor((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.
            model.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()

            # plot using visdom
            logger.vizkv('eprewmean', t, mean_100ep_reward)

        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))
                model.save(save_path)
                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))
        model.load(save_path)

    return model
Exemple #12
0
def learn(*,
          network,
          env,
          total_timesteps,
          eval_env=None,
          seed=None,
          nsteps=2048,
          ent_coef=0.0,
          lr=3e-4,
          vf_coef=0.5,
          max_grad_norm=0.5,
          gamma=0.99,
          lam=0.95,
          log_interval=10,
          nminibatches=4,
          noptepochs=4,
          cliprange=0.2,
          save_interval=0,
          load_path=None,
          model_fn=None,
          update_fn=None,
          init_fn=None,
          mpi_rank_weight=1,
          comm=None,
          **network_kwargs):
    '''
    Learn policy using PPO algorithm (https://arxiv.org/abs/1707.06347)

    Parameters:
    ----------

    network:                          policy network architecture. Either string (mlp, lstm, lnlstm, cnn_lstm, cnn, cnn_small, conv_only - see baselines.common/models.py for full list)
                                      specifying the standard network architecture, or a function that takes tensorflow tensor as input and returns
                                      tuple (output_tensor, extra_feed) where output tensor is the last network layer output, extra_feed is None for feed-forward
                                      neural nets, and extra_feed is a dictionary describing how to feed state into the network for recurrent neural nets.
                                      See common/models.py/lstm for more details on using recurrent nets in policies

    env: baselines.common.vec_env.VecEnv     environment. Needs to be vectorized for parallel environment simulation.
                                      The environments produced by gym.make can be wrapped using baselines.common.vec_env.DummyVecEnv class.


    nsteps: int                       number of steps of the vectorized environment per update (i.e. batch size is nsteps * nenv where
                                      nenv is number of environment copies simulated in parallel)

    total_timesteps: int              number of timesteps (i.e. number of actions taken in the environment)

    ent_coef: float                   policy entropy coefficient in the optimization objective

    lr: float or function             learning rate, constant or a schedule function [0,1] -> R+ where 1 is beginning of the
                                      training and 0 is the end of the training.

    vf_coef: float                    value function loss coefficient in the optimization objective

    max_grad_norm: float or None      gradient norm clipping coefficient

    gamma: float                      discounting factor

    lam: float                        advantage estimation discounting factor (lambda in the paper)

    log_interval: int                 number of timesteps between logging events

    nminibatches: int                 number of training minibatches per update. For recurrent policies,
                                      should be smaller or equal than number of environments run in parallel.

    noptepochs: int                   number of training epochs per update

    cliprange: float or function      clipping range, constant or schedule function [0,1] -> R+ where 1 is beginning of the training
                                      and 0 is the end of the training

    save_interval: int                number of timesteps between saving events

    load_path: str                    path to load the model from

    **network_kwargs:                 keyword arguments to the policy / network builder. See baselines.common/policies.py/build_policy and arguments to a particular type of network
                                      For instance, 'mlp' network architecture has arguments num_hidden and num_layers.



    '''

    set_global_seeds(seed)

    if isinstance(lr, float): lr = constfn(lr)
    else: assert callable(lr)
    if isinstance(cliprange, float): cliprange = constfn(cliprange)
    else: assert callable(cliprange)
    total_timesteps = int(total_timesteps)

    policy = build_policy(env, network, **network_kwargs)

    # Get the nb of env
    nenvs = env.num_envs

    # Get state_space and action_space
    ob_space = env.observation_space
    ac_space = env.action_space

    # Calculate the batch_size
    nbatch = nenvs * nsteps
    nbatch_train = nbatch // nminibatches
    is_mpi_root = (MPI is None or MPI.COMM_WORLD.Get_rank() == 0)

    # Instantiate the model object (that creates act_model and train_model)
    if model_fn is None:
        from ptbaselines.algos.ppo2.model import Model
        model_fn = Model

    model = model_fn(policy=policy,
                     ob_space=ob_space,
                     ac_space=ac_space,
                     nbatch_act=nenvs,
                     nbatch_train=nbatch_train,
                     nsteps=nsteps,
                     ent_coef=ent_coef,
                     vf_coef=vf_coef,
                     max_grad_norm=max_grad_norm,
                     comm=comm,
                     mpi_rank_weight=mpi_rank_weight)

    if load_path is not None:
        model.load(load_path)
    # Instantiate the runner object
    runner = Runner(env=env, model=model, nsteps=nsteps, gamma=gamma, lam=lam)
    if eval_env is not None:
        eval_runner = Runner(env=eval_env,
                             model=model,
                             nsteps=nsteps,
                             gamma=gamma,
                             lam=lam)

    epinfobuf = deque(maxlen=100)
    if eval_env is not None:
        eval_epinfobuf = deque(maxlen=100)

    if init_fn is not None:
        init_fn()

    # Start total timer
    tfirststart = time.perf_counter()

    nupdates = total_timesteps // nbatch
    for update in range(1, nupdates + 1):
        assert nbatch % nminibatches == 0
        # Start timer
        tstart = time.perf_counter()
        frac = 1.0 - (update - 1.0) / nupdates
        # Calculate the learning rate
        lrnow = lr(frac)
        # Calculate the cliprange
        cliprangenow = cliprange(frac)

        if update % log_interval == 0 and is_mpi_root:
            logger.info('Stepping environment...')

        # Get minibatch
        obs, returns, masks, actions, values, neglogpacs, states, epinfos = runner.run(
        )  #pylint: disable=E0632
        if eval_env is not None:
            eval_obs, eval_returns, eval_masks, eval_actions, eval_values, eval_neglogpacs, eval_states, eval_epinfos = eval_runner.run(
            )  #pylint: disable=E0632

        if update % log_interval == 0 and is_mpi_root: logger.info('Done.')

        epinfobuf.extend(epinfos)
        if eval_env is not None:
            eval_epinfobuf.extend(eval_epinfos)

        # Here what we're going to do is for each minibatch calculate the loss and append it.
        mblossvals = []
        if states is None:  # nonrecurrent version
            # Index of each element of batch_size
            # Create the indices array
            inds = np.arange(nbatch)
            for _ in range(noptepochs):
                # Randomize the indexes
                np.random.shuffle(inds)
                # 0 to batch_size with batch_train_size step
                for start in range(0, nbatch, nbatch_train):
                    end = start + nbatch_train
                    mbinds = inds[start:end]
                    slices = (arr[mbinds]
                              for arr in (obs, returns, masks, actions, values,
                                          neglogpacs))
                    slices = torch_utils.toTensor(slices)
                    mblossvals.append(
                        torch_utils.toNumpy(
                            model.train(lrnow, cliprangenow, *slices)))
        else:  # recurrent version
            assert nenvs % nminibatches == 0
            envsperbatch = nenvs // nminibatches
            envinds = np.arange(nenvs)
            flatinds = np.arange(nenvs * nsteps).reshape(nenvs, nsteps)
            for _ in range(noptepochs):
                np.random.shuffle(envinds)
                for start in range(0, nenvs, envsperbatch):
                    end = start + envsperbatch
                    mbenvinds = envinds[start:end]
                    mbflatinds = flatinds[mbenvinds].ravel()
                    slices = (arr[mbflatinds]
                              for arr in (obs, returns, masks, actions, values,
                                          neglogpacs))
                    slices.append(states[mbenvinds])
                    slices = torch_utils.toTensor(slices)
                    mblossvals.append(
                        torch_utils.toNumpy(
                            model.train(lrnow, cliprangenow, *slices)))

        # Feedforward --> get losses --> update
        lossvals = np.mean(mblossvals, axis=0)
        # End timer
        tnow = time.perf_counter()
        # Calculate the fps (frame per second)
        fps = int(nbatch / (tnow - tstart))

        if update_fn is not None:
            update_fn(update)

        if update % log_interval == 0 or update == 1:
            # Calculates if value function is a good predicator of the returns (ev > 1)
            # or if it's just worse than predicting nothing (ev =< 0)
            ev = explained_variance(values, returns)
            logger.logkv("misc/serial_timesteps", update * nsteps)
            logger.logkv("misc/nupdates", update)
            logger.logkv("misc/total_timesteps", update * nbatch)
            logger.logkv("fps", fps)
            logger.logkv("batchsize", nbatch)
            logger.logkv("misc/explained_variance", float(ev))
            logger.logkv('eprewmean',
                         safemean([epinfo['r'] for epinfo in epinfobuf]))
            logger.logkv('eplenmean',
                         safemean([epinfo['l'] for epinfo in epinfobuf]))
            if eval_env is not None:
                logger.logkv(
                    'eval_eprewmean',
                    safemean([epinfo['r'] for epinfo in eval_epinfobuf]))
                logger.logkv(
                    'eval_eplenmean',
                    safemean([epinfo['l'] for epinfo in eval_epinfobuf]))
            logger.logkv('misc/time_elapsed', tnow - tfirststart)
            for (lossval, lossname) in zip(lossvals, model.loss_names):
                logger.logkv('loss/' + lossname, lossval)
            logger.dumpkvs()

            # plot using visdom
            timesteps = update * nbatch
            logger.vizkv('eprewmean', timesteps,
                         safemean([epinfo['r'] for epinfo in epinfobuf]))
            logger.vizkv('eplenmean', timesteps,
                         safemean([epinfo['l'] for epinfo in epinfobuf]))
            for (lossval, lossname) in zip(lossvals, model.loss_names):
                logger.vizkv('loss/' + lossname, timesteps, lossval)

        if save_interval and (update % save_interval == 0 or update
                              == 1) and logger.get_dir() and is_mpi_root:
            checkdir = osp.join(logger.get_dir(), 'checkpoints')
            os.makedirs(checkdir, exist_ok=True)
            savepath = osp.join(checkdir, '%.5i' % update) + '.pth'
            print('Saving to', savepath)
            model.save(savepath)

    return model
Exemple #13
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    def run(self):
        # We initialize the lists that will contain the mb of experiences
        mb_obs, mb_rewards, mb_actions, mb_values, mb_dones = [],[],[],[],[]
        mb_states = self.states
        epinfos = []
        for n in range(self.nsteps):
            # Given observations, take action and value (V(s))
            # We already have self.obs because Runner superclass run self.obs[:] = env.reset() on init
            outputs = self.model.step(torch_utils.toTensor(self.obs).float(),
                                      S=self.states,
                                      M=self.dones)
            actions, values, states, _ = torch_utils.toNumpy(outputs)

            # Append the experiences
            mb_obs.append(np.copy(self.obs))
            mb_actions.append(actions)
            mb_values.append(values)
            mb_dones.append(self.dones)

            # Take actions in env and look the results
            obs, rewards, dones, infos = self.env.step(actions)
            for info in infos:
                maybeepinfo = info.get('episode')
                if maybeepinfo: epinfos.append(maybeepinfo)
            self.states = states
            self.dones = dones
            self.obs = obs
            mb_rewards.append(rewards)
        mb_dones.append(self.dones)

        # Batch of steps to batch of rollouts
        mb_obs = np.asarray(mb_obs, dtype=np.float32).swapaxes(1, 0).reshape(
            self.batch_ob_shape)
        mb_rewards = np.asarray(mb_rewards, dtype=np.float32).swapaxes(1, 0)
        mb_actions = np.asarray(mb_actions).swapaxes(1, 0)
        mb_values = np.asarray(mb_values, dtype=np.float32).swapaxes(1, 0)
        mb_dones = np.asarray(mb_dones, dtype=np.bool).swapaxes(1, 0)
        mb_masks = mb_dones[:, :-1]
        mb_dones = mb_dones[:, 1:]

        if self.gamma > 0.0:
            # Discount/bootstrap off value fn
            last_values = self.model.value(torch_utils.toTensor(
                self.obs).float(),
                                           S=self.states,
                                           M=self.dones)
            last_values = torch_utils.toNumpy(last_values).tolist()
            for n, (rewards, dones,
                    value) in enumerate(zip(mb_rewards, mb_dones,
                                            last_values)):
                rewards = rewards.tolist()
                dones = dones.tolist()
                if dones[-1] == 0:
                    rewards = discount_with_dones(rewards + [value],
                                                  dones + [0], self.gamma)[:-1]
                else:
                    rewards = discount_with_dones(rewards, dones, self.gamma)

                mb_rewards[n] = rewards

        mb_actions = mb_actions.reshape(
            mb_actions.shape[0] * mb_actions.shape[1], *mb_actions.shape[2:])
        mb_rewards = mb_rewards.flatten()
        mb_values = mb_values.flatten()
        mb_masks = mb_masks.flatten()
        return mb_obs, mb_states, mb_rewards, mb_masks, mb_actions, mb_values, epinfos