Add PPO Atari LSTM example

README.md

@@ -87,6 +87,10 @@ python cleanrl/sac_continuous_action.py --gym-id MinitaurBulletDuckEnv-v0
 poetry install -E procgen
 python cleanrl/ppo_procgen.py --gym-id starpilot
 python cleanrl/ppg_procgen.py --gym-id starpilot
+
+# ppo + lstm
+python cleanrl/ppo_atari_lstm.py --gym-id BreakoutNoFrameskip-v4
+python cleanrl/ppo_memory_env_lstm.py
 ```
 
 You may also use a prebuilt development environment hosted in Gitpod:

cleanrl/ppo_atari_lstm.py

@@ -0,0 +1,385 @@
+import argparse
+import os
+import random
+import time
+from distutils.util import strtobool
+
+import gym
+import numpy as np
+import torch
+import torch.nn as nn
+import torch.optim as optim
+from torch.distributions.categorical import Categorical
+from torch.utils.tensorboard import SummaryWriter
+
+from stable_baselines3.common.atari_wrappers import (  # isort:skip
+    ClipRewardEnv,
+    EpisodicLifeEnv,
+    FireResetEnv,
+    MaxAndSkipEnv,
+    NoopResetEnv,
+)
+
+
+def parse_args():
+    # fmt: off
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--exp-name", type=str, default=os.path.basename(__file__).rstrip(".py"),
+        help="the name of this experiment")
+    parser.add_argument("--gym-id", type=str, default="BreakoutNoFrameskip-v4",
+        help="the id of the gym environment")
+    parser.add_argument("--learning-rate", type=float, default=2.5e-4,
+        help="the learning rate of the optimizer")
+    parser.add_argument("--seed", type=int, default=1,
+        help="seed of the experiment")
+    parser.add_argument("--total-timesteps", type=int, default=10000000,
+        help="total timesteps of the experiments")
+    parser.add_argument("--torch-deterministic", type=lambda x: bool(strtobool(x)), default=True, nargs="?", const=True,
+        help="if toggled, `torch.backends.cudnn.deterministic=False`")
+    parser.add_argument("--cuda", type=lambda x: bool(strtobool(x)), default=True, nargs="?", const=True,
+        help="if toggled, cuda will be enabled by default")
+    parser.add_argument("--track", type=lambda x: bool(strtobool(x)), default=False, nargs="?", const=True,
+        help="if toggled, this experiment will be tracked with Weights and Biases")
+    parser.add_argument("--wandb-project-name", type=str, default="cleanRL",
+        help="the wandb's project name")
+    parser.add_argument("--wandb-entity", type=str, default=None,
+        help="the entity (team) of wandb's project")
+    parser.add_argument("--capture-video", type=lambda x: bool(strtobool(x)), default=False, nargs="?", const=True,
+        help="weather to capture videos of the agent performances (check out `videos` folder)")
+
+    # Algorithm specific arguments
+    parser.add_argument("--num-envs", type=int, default=8,
+        help="the number of parallel game environments")
+    parser.add_argument("--num-steps", type=int, default=128,
+        help="the number of steps to run in each environment per policy rollout")
+    parser.add_argument("--anneal-lr", type=lambda x: bool(strtobool(x)), default=True, nargs="?", const=True,
+        help="Toggle learning rate annealing for policy and value networks")
+    parser.add_argument("--gae", type=lambda x: bool(strtobool(x)), default=True, nargs="?", const=True,
+        help="Use GAE for advantage computation")
+    parser.add_argument("--gamma", type=float, default=0.99,
+        help="the discount factor gamma")
+    parser.add_argument("--gae-lambda", type=float, default=0.95,
+        help="the lambda for the general advantage estimation")
+    parser.add_argument("--num-minibatches", type=int, default=4,
+        help="the number of mini-batches")
+    parser.add_argument("--update-epochs", type=int, default=4,
+        help="the K epochs to update the policy")
+    parser.add_argument("--norm-adv", type=lambda x: bool(strtobool(x)), default=True, nargs="?", const=True,
+        help="Toggles advantages normalization")
+    parser.add_argument("--clip-coef", type=float, default=0.1,
+        help="the surrogate clipping coefficient")
+    parser.add_argument("--clip-vloss", type=lambda x: bool(strtobool(x)), default=True, nargs="?", const=True,
+        help="Toggles whether or not to use a clipped loss for the value function, as per the paper.")
+    parser.add_argument("--ent-coef", type=float, default=0.01,
+        help="coefficient of the entropy")
+    parser.add_argument("--vf-coef", type=float, default=0.5,
+        help="coefficient of the value function")
+    parser.add_argument("--max-grad-norm", type=float, default=0.5,
+        help="the maximum norm for the gradient clipping")
+    parser.add_argument("--target-kl", type=float, default=None,
+        help="the target KL divergence threshold")
+    args = parser.parse_args()
+    args.batch_size = int(args.num_envs * args.num_steps)
+    args.minibatch_size = int(args.batch_size // args.num_minibatches)
+    # fmt: on
+    return args
+
+
+def make_env(gym_id, seed, idx, capture_video, run_name):
+    def thunk():
+        env = gym.make(gym_id)
+        env = gym.wrappers.RecordEpisodeStatistics(env)
+        if capture_video:
+            if idx == 0:
+                env = gym.wrappers.RecordVideo(env, f"videos/{run_name}")
+        env = NoopResetEnv(env, noop_max=30)
+        env = MaxAndSkipEnv(env, skip=4)
+        env = EpisodicLifeEnv(env)
+        if "FIRE" in env.unwrapped.get_action_meanings():
+            env = FireResetEnv(env)
+        env = ClipRewardEnv(env)
+        env = gym.wrappers.ResizeObservation(env, (84, 84))
+        env = gym.wrappers.GrayScaleObservation(env)
+        env = gym.wrappers.FrameStack(env, 1)
+        env.seed(seed)
+        env.action_space.seed(seed)
+        env.observation_space.seed(seed)
+        return env
+
+    return thunk
+
+
+def layer_init(layer, std=np.sqrt(2), bias_const=0.0):
+    torch.nn.init.orthogonal_(layer.weight, std)
+    torch.nn.init.constant_(layer.bias, bias_const)
+    return layer
+
+
+class Agent(nn.Module):
+    def __init__(self, envs):
+        super(Agent, self).__init__()
+        self.network = nn.Sequential(
+            layer_init(nn.Conv2d(1, 32, 8, stride=4)),
+            nn.ReLU(),
+            layer_init(nn.Conv2d(32, 64, 4, stride=2)),
+            nn.ReLU(),
+            layer_init(nn.Conv2d(64, 64, 3, stride=1)),
+            nn.ReLU(),
+            nn.Flatten(),
+            layer_init(nn.Linear(64 * 7 * 7, 512)),
+            nn.ReLU(),
+        )
+        self.lstm = nn.LSTM(512, 128)
+        for name, param in self.lstm.named_parameters():
+            if "bias" in name:
+                nn.init.constant_(param, 0)
+            elif "weight" in name:
+                nn.init.orthogonal_(param, 1.0)
+        self.actor = layer_init(nn.Linear(128, envs.single_action_space.n), std=0.01)
+        self.critic = layer_init(nn.Linear(128, 1), std=1)
+
+    def get_states(self, x, lstm_state, done):
+        hidden = self.network(x / 255.0)
+
+        # LSTM logic
+        batch_size = lstm_state[0].shape[1]
+        hidden = hidden.reshape((-1, batch_size, self.lstm.input_size))
+        done = done.reshape((-1, batch_size))
+        new_hidden = []
+        for h, d in zip(hidden, done):
+            h, lstm_state = self.lstm(
+                h.unsqueeze(0),
+                (
+                    (1.0 - d).view(1, -1, 1) * lstm_state[0],
+                    (1.0 - d).view(1, -1, 1) * lstm_state[1],
+                ),
+            )
+            new_hidden += [h]
+        new_hidden = torch.flatten(torch.cat(new_hidden), 0, 1)
+        return new_hidden, lstm_state
+
+    def get_value(self, x, lstm_state, done):
+        hidden, _ = self.get_states(x, lstm_state, done)
+        return self.critic(hidden)
+
+    def get_action_and_value(self, x, lstm_state, done, action=None):
+        hidden, lstm_state = self.get_states(x, lstm_state, done)
+        logits = self.actor(hidden)
+        probs = Categorical(logits=logits)
+        if action is None:
+            action = probs.sample()
+        return action, probs.log_prob(action), probs.entropy(), self.critic(hidden), lstm_state
+
+
+if __name__ == "__main__":
+    args = parse_args()
+    run_name = f"{args.gym_id}__{args.exp_name}__{args.seed}__{int(time.time())}"
+    if args.track:
+        import wandb
+
+        wandb.init(
+            project=args.wandb_project_name,
+            entity=args.wandb_entity,
+            sync_tensorboard=True,
+            config=vars(args),
+            name=run_name,
+            monitor_gym=True,
+            save_code=True,
+        )
+    writer = SummaryWriter(f"runs/{run_name}")
+    writer.add_text(
+        "hyperparameters",
+        "|param|value|\n|-|-|\n%s" % ("\n".join([f"|{key}|{value}|" for key, value in vars(args).items()])),
+    )
+
+    # TRY NOT TO MODIFY: seeding
+    random.seed(args.seed)
+    np.random.seed(args.seed)
+    torch.manual_seed(args.seed)
+    torch.backends.cudnn.deterministic = args.torch_deterministic
+
+    device = torch.device("cuda" if torch.cuda.is_available() and args.cuda else "cpu")
+
+    # env setup
+    envs = gym.vector.SyncVectorEnv(
+        [make_env(args.gym_id, args.seed + i, i, args.capture_video, run_name) for i in range(args.num_envs)]
+    )
+    assert isinstance(envs.single_action_space, gym.spaces.Discrete), "only discrete action space is supported"
+
+    agent = Agent(envs).to(device)
+    optimizer = optim.Adam(agent.parameters(), lr=args.learning_rate, eps=1e-5)
+
+    # ALGO Logic: Storage setup
+    obs = torch.zeros((args.num_steps, args.num_envs) + envs.single_observation_space.shape).to(device)
+    actions = torch.zeros((args.num_steps, args.num_envs) + envs.single_action_space.shape).to(device)
+    logprobs = torch.zeros((args.num_steps, args.num_envs)).to(device)
+    rewards = torch.zeros((args.num_steps, args.num_envs)).to(device)
+    dones = torch.zeros((args.num_steps, args.num_envs)).to(device)
+    values = torch.zeros((args.num_steps, args.num_envs)).to(device)
+
+    # TRY NOT TO MODIFY: start the game
+    global_step = 0
+    start_time = time.time()
+    next_obs = torch.Tensor(envs.reset()).to(device)
+    next_done = torch.zeros(args.num_envs).to(device)
+    next_lstm_state = (
+        torch.zeros(agent.lstm.num_layers, args.num_envs, agent.lstm.hidden_size).to(device),
+        torch.zeros(agent.lstm.num_layers, args.num_envs, agent.lstm.hidden_size).to(device),
+    )  # hidden and cell states (see https://youtu.be/8HyCNIVRbSU)
+    num_updates = args.total_timesteps // args.batch_size
+
+    for update in range(1, num_updates + 1):
+        initial_lstm_state = (next_lstm_state[0].clone(), next_lstm_state[1].clone())
+        # Annealing the rate if instructed to do so.
+        if args.anneal_lr:
+            frac = 1.0 - (update - 1.0) / num_updates
+            lrnow = frac * args.learning_rate
+            optimizer.param_groups[0]["lr"] = lrnow
+
+        for step in range(0, args.num_steps):
+            global_step += 1 * args.num_envs
+            obs[step] = next_obs
+            dones[step] = next_done
+
+            # ALGO LOGIC: action logic
+            with torch.no_grad():
+                action, logprob, _, value, next_lstm_state = agent.get_action_and_value(next_obs, next_lstm_state, next_done)
+                values[step] = value.flatten()
+            actions[step] = action
+            logprobs[step] = logprob
+
+            # TRY NOT TO MODIFY: execute the game and log data.
+            next_obs, reward, done, info = envs.step(action.cpu().numpy())
+            rewards[step] = torch.tensor(reward).to(device).view(-1)
+            next_obs, next_done = torch.Tensor(next_obs).to(device), torch.Tensor(done).to(device)
+
+            for item in info:
+                if "episode" in item.keys():
+                    print(f"global_step={global_step}, episodic_return={item['episode']['r']}")
+                    writer.add_scalar("charts/episodic_return", item["episode"]["r"], global_step)
+                    writer.add_scalar("charts/episodic_length", item["episode"]["l"], global_step)
+                    break
+
+        # bootstrap value if not done
+        with torch.no_grad():
+            next_value = agent.get_value(
+                next_obs,
+                next_lstm_state,
+                next_done,
+            ).reshape(1, -1)
+            if args.gae:
+                advantages = torch.zeros_like(rewards).to(device)
+                lastgaelam = 0
+                for t in reversed(range(args.num_steps)):
+                    if t == args.num_steps - 1:
+                        nextnonterminal = 1.0 - next_done
+                        nextvalues = next_value
+                    else:
+                        nextnonterminal = 1.0 - dones[t + 1]
+                        nextvalues = values[t + 1]
+                    delta = rewards[t] + args.gamma * nextvalues * nextnonterminal - values[t]
+                    advantages[t] = lastgaelam = delta + args.gamma * args.gae_lambda * nextnonterminal * lastgaelam
+                returns = advantages + values
+            else:
+                returns = torch.zeros_like(rewards).to(device)
+                for t in reversed(range(args.num_steps)):
+                    if t == args.num_steps - 1:
+                        nextnonterminal = 1.0 - next_done
+                        next_return = next_value
+                    else:
+                        nextnonterminal = 1.0 - dones[t + 1]
+                        next_return = returns[t + 1]
+                    returns[t] = rewards[t] + args.gamma * nextnonterminal * next_return
+                advantages = returns - values
+
+        # flatten the batch
+        b_obs = obs.reshape((-1,) + envs.single_observation_space.shape)
+        b_logprobs = logprobs.reshape(-1)
+        b_actions = actions.reshape((-1,) + envs.single_action_space.shape)
+        b_dones = dones.reshape(-1)
+        b_advantages = advantages.reshape(-1)
+        b_returns = returns.reshape(-1)
+        b_values = values.reshape(-1)
+
+        # Optimizing the policy and value network
+        assert args.num_envs % args.num_minibatches == 0
+        envsperbatch = args.num_envs // args.num_minibatches
+        envinds = np.arange(args.num_envs)
+        flatinds = np.arange(args.batch_size).reshape(args.num_steps, args.num_envs)
+        clipfracs = []
+        for epoch in range(args.update_epochs):
+            np.random.shuffle(envinds)
+            for start in range(0, args.num_envs, envsperbatch):
+                end = start + envsperbatch
+                mbenvinds = envinds[start:end]
+                mb_inds = flatinds[:, mbenvinds].ravel()  # be really careful about the index
+
+                _, newlogprob, entropy, newvalue, _ = agent.get_action_and_value(
+                    b_obs[mb_inds],
+                    (initial_lstm_state[0][:, mbenvinds], initial_lstm_state[1][:, mbenvinds]),
+                    b_dones[mb_inds],
+                    b_actions.long()[mb_inds],
+                )
+                logratio = newlogprob - b_logprobs[mb_inds]
+                ratio = logratio.exp()
+
+                with torch.no_grad():
+                    # calculate approx_kl http://joschu.net/blog/kl-approx.html
+                    old_approx_kl = (-logratio).mean()
+                    approx_kl = ((ratio - 1) - logratio).mean()
+                    clipfracs += [((ratio - 1.0).abs() > args.clip_coef).float().mean().item()]
+
+                mb_advantages = b_advantages[mb_inds]
+                if args.norm_adv:
+                    mb_advantages = (mb_advantages - mb_advantages.mean()) / (mb_advantages.std() + 1e-8)
+
+                # Policy loss
+                pg_loss1 = -mb_advantages * ratio
+                pg_loss2 = -mb_advantages * torch.clamp(ratio, 1 - args.clip_coef, 1 + args.clip_coef)
+                pg_loss = torch.max(pg_loss1, pg_loss2).mean()
+
+                # Value loss
+                newvalue = newvalue.view(-1)
+                if args.clip_vloss:
+                    v_loss_unclipped = (newvalue - b_returns[mb_inds]) ** 2
+                    v_clipped = b_values[mb_inds] + torch.clamp(
+                        newvalue - b_values[mb_inds],
+                        -args.clip_coef,
+                        args.clip_coef,
+                    )
+                    v_loss_clipped = (v_clipped - b_returns[mb_inds]) ** 2
+                    v_loss_max = torch.max(v_loss_unclipped, v_loss_clipped)
+                    v_loss = 0.5 * v_loss_max.mean()
+                else:
+                    v_loss = 0.5 * ((newvalue - b_returns[mb_inds]) ** 2).mean()
+
+                entropy_loss = entropy.mean()
+                loss = pg_loss - args.ent_coef * entropy_loss + v_loss * args.vf_coef
+
+                optimizer.zero_grad()
+                loss.backward()
+                nn.utils.clip_grad_norm_(agent.parameters(), args.max_grad_norm)
+                optimizer.step()
+
+            if args.target_kl is not None:
+                if approx_kl > args.target_kl:
+                    break
+
+        y_pred, y_true = b_values.cpu().numpy(), b_returns.cpu().numpy()
+        var_y = np.var(y_true)
+        explained_var = np.nan if var_y == 0 else 1 - np.var(y_true - y_pred) / var_y
+
+        # TRY NOT TO MODIFY: record rewards for plotting purposes
+        writer.add_scalar("charts/learning_rate", optimizer.param_groups[0]["lr"], global_step)
+        writer.add_scalar("losses/value_loss", v_loss.item(), global_step)
+        writer.add_scalar("losses/policy_loss", pg_loss.item(), global_step)
+        writer.add_scalar("losses/entropy", entropy_loss.item(), global_step)
+        writer.add_scalar("losses/old_approx_kl", old_approx_kl.item(), global_step)
+        writer.add_scalar("losses/approx_kl", approx_kl.item(), global_step)
+        writer.add_scalar("losses/clipfrac", np.mean(clipfracs), global_step)
+        writer.add_scalar("losses/explained_variance", explained_var, global_step)
+        print("SPS:", int(global_step / (time.time() - start_time)))
+        writer.add_scalar("charts/SPS", int(global_step / (time.time() - start_time)), global_step)
+
+    envs.close()
+    writer.close()