Running PPO (not working yet)

This commit is contained in:
Antonin RAFFIN 2019-09-18 15:35:17 +02:00
parent 54dd7ea60d
commit 6bb7e183d2
10 changed files with 215 additions and 157 deletions

28
tests/test_run.py Normal file
View file

@ -0,0 +1,28 @@
import os
import gym
from torchy_baselines import TD3, CEMRL, PPO
# def test_pendulum():
# model = TD3('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[64, 64]), start_timesteps=100, verbose=1)
# model.learn(total_timesteps=500, eval_freq=100)
# model.save("test_save")
# model.load("test_save")
# os.remove("test_save.pth")
#
#
# def test_cemrl():
# model = CEMRL('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[16]), pop_size=2, n_grad=1,
# start_timesteps=100, verbose=1)
# model.learn(total_timesteps=1000, eval_freq=500)
# model.save("test_save")
# model.load("test_save")
# os.remove("test_save.pth")
def test_ppo():
model = PPO('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[16]), verbose=1)
model.learn(total_timesteps=1000, eval_freq=500)
# model.save("test_save")
# model.load("test_save")
# os.remove("test_save.pth")

View file

@ -1,21 +0,0 @@
import os
import gym
from torchy_baselines import TD3, CEMRL
def test_pendulum():
model = TD3('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[64, 64]), start_timesteps=100, verbose=1)
model.learn(total_timesteps=500, eval_freq=100)
model.save("test_save")
model.load("test_save")
os.remove("test_save.pth")
def test_cemrl():
model = CEMRL('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[16]), pop_size=2, n_grad=1,
start_timesteps=100, verbose=1)
model.learn(total_timesteps=1000, eval_freq=500)
model.save("test_save")
model.load("test_save")
os.remove("test_save.pth")

View file

@ -1,4 +1,5 @@
from torchy_baselines.td3 import TD3
from torchy_baselines.cem_rl import CEMRL
from torchy_baselines.ppo import PPO
from torchy_baselines.td3 import TD3
__version__ = "0.0.2"

View file

@ -4,7 +4,7 @@ import torch as th
import torch.nn.functional as F
import numpy as np
from torchy_baselines import TD3
from torchy_baselines.td3.td3 import TD3
from torchy_baselines.common.evaluation import evaluate_policy
from torchy_baselines.cem_rl.cem import CEM

View file

@ -1,3 +1,4 @@
import torch as th
import torch.nn as nn

View file

@ -1,6 +1,8 @@
import numpy as np
import torch as th
from torchy_baselines.common.utils import discount_cumsum
class ReplayBuffer(object):
"""
@ -43,14 +45,74 @@ class ReplayBuffer(object):
self.full = True
self.pos = 0
def reset(self):
self.pos = 0
self.full = False
def sample(self, batch_size):
upper_bound = self.buffer_size if self.full else self.pos
batch_inds = th.LongTensor(
np.random.randint(0, upper_bound, size=batch_size))
return self._get_samples(batch_inds)
def _get_samples(self, batch_inds):
return (self.states[batch_inds].to(self.device),
self.actions[batch_inds].to(self.device),
self.next_states[batch_inds].to(self.device),
self.dones[batch_inds].to(self.device),
self.rewards[batch_inds].to(self.device))
class RolloutBuffer(ReplayBuffer):
def __init__(self, buffer_size, state_dim, action_dim, device='cpu',
lambda_=1, gamma=0.99):
super(RolloutBuffer, self).__init__(buffer_size, state_dim, action_dim, device)
self.lambda_ = lambda_
self.gamma = gamma
# TODO: add n_envs
self.returns = th.zeros(self.buffer_size, 1)
self.values = th.zeros(self.buffer_size, 1)
self.log_probs = th.zeros(self.buffer_size, 1)
self.advantages = th.zeros(self.buffer_size, 1)
self.path_start_idx = 0
def finish_path(self, last_value=0):
"""
From https://github.com/openai/spinningup/blob/master/spinup/algos/ppo/ppo.py
"""
if self.full:
self.pos = self.buffer_size
path_slice = slice(self.path_start_idx, self.pos)
rewards = np.append(self.rewards[path_slice].detach().cpu().numpy(), last_value)
values = np.append(self.values[path_slice].detach().cpu().numpy(), last_value)
# the next two lines implement GAE-Lambda advantage calculation
deltas = rewards[:-1] + self.gamma * values[1:] - values[:-1]
self.advantages[path_slice, 0] = th.FloatTensor(discount_cumsum(deltas, self.gamma * self.lambda_).copy())
# the next line computes rewards-to-go, to be targets for the value function
self.returns[path_slice, 0] = th.FloatTensor(discount_cumsum(rewards, self.gamma)[:-1].copy())
self.path_start_idx = self.pos
def add(self, state, next_state, action, reward, done, value, log_prob):
self.values[self.pos] = th.FloatTensor([value])
self.log_probs[self.pos] = th.FloatTensor([log_prob])
super(RolloutBuffer, self).add(state, next_state, action, reward, done)
def reset(self):
self.path_start_idx = 0
super(RolloutBuffer, self).reset()
def _get_samples(self, batch_inds):
return (self.states[batch_inds].to(self.device),
self.actions[batch_inds].to(self.device),
self.next_states[batch_inds].to(self.device),
self.dones[batch_inds].to(self.device),
self.rewards[batch_inds].to(self.device),
self.values[batch_inds].to(self.device),
self.log_probs[batch_inds].to(self.device),
self.advantages[batch_inds].to(self.device),
self.returns[batch_inds].to(self.device))

View file

@ -1,5 +1,6 @@
import random
import scipy.signal
import torch as th
import numpy as np
@ -18,3 +19,36 @@ def set_random_seed(seed, using_cuda=False):
# Make CuDNN Determinist
th.backends.cudnn.deterministic = True
th.cuda.manual_seed(seed)
# From stable_baselines.common.math_util
# def discount(vector, gamma):
# """
# computes discounted sums along 0th dimension of vector x.
# y[t] = x[t] + gamma*x[t+1] + gamma^2*x[t+2] + ... + gamma^k x[t+k],
# where k = len(x) - t - 1
#
# :param vector: (np.ndarray) the input vector
# :param gamma: (float) the discount value
# :return: (np.ndarray) the output vector
# """
# assert vector.ndim >= 1
# return scipy.signal.lfilter([1], [1, -gamma], vector[::-1], axis=0)[::-1]
def discount_cumsum(x, discount):
"""
magic from rllab for computing discounted cumulative sums of vectors.
input:
vector x,
[x0,
x1,
x2]
output:
[x0 + discount * x1 + discount^2 * x2,
x1 + discount * x2,
x2]
"""
return scipy.signal.lfilter([1], [1, float(-discount)], x[::-1], axis=0)[::-1]

View file

@ -0,0 +1 @@
from torchy_baselines.ppo.ppo import PPO

View file

@ -2,52 +2,7 @@ import torch as th
import torch.nn as nn
from torch.distributions import Normal
from torchy_baselines.common.policies import BasePolicy, register_policy, create_mlp, BaseNetwork
class Actor(BaseNetwork):
def __init__(self, state_dim, action_dim, net_arch=None, activation_fn=nn.ReLU):
super(Actor, self).__init__()
if net_arch is None:
net_arch = [64, 64]
# TODO: orthogonal initialization?
actor_net = create_mlp(state_dim, action_dim, net_arch, activation_fn, squash_out=True)
self.actor_net = nn.Sequential(*actor_net)
def forward(self, x):
return self.actor_net(x)
class Critic(BaseNetwork):
def __init__(self, state_dim, action_dim,
net_arch=None, activation_fn=nn.ReLU):
super(Critic, self).__init__()
if net_arch is None:
net_arch = [400, 300]
# TODO: solve pytorch parameter registration
# for _ in range(n_critics):
# q_net = create_mlp(state_dim + action_dim, 1, net_arch, activation_fn)
# self.q_net = nn.Sequential(*q_net)
# self.q_networks.append(self.q_net)
q1_net = create_mlp(state_dim + action_dim, 1, net_arch, activation_fn)
self.q1_net = nn.Sequential(*q1_net)
q2_net = create_mlp(state_dim + action_dim, 1, net_arch, activation_fn)
self.q2_net = nn.Sequential(*q2_net)
self.q_networks = [self.q1_net, self.q2_net]
def forward(self, obs, action):
qvalue_input = th.cat([obs, action], dim=1)
return [q_net(qvalue_input) for q_net in self.q_networks]
def q1_forward(self, obs, action):
return self.q_networks[0](th.cat([obs, action], dim=1))
from torchy_baselines.common.policies import BasePolicy, register_policy, create_mlp
class PPOPolicy(BasePolicy):
@ -71,7 +26,7 @@ class PPOPolicy(BasePolicy):
self._build(learning_rate)
def _build(self, learning_rate):
shared_net = create_mlp(self.state_dim, output_dim=-1, self.net_arch, self.activation_fn)
shared_net = create_mlp(self.state_dim, output_dim=-1, net_arch=self.net_arch, activation_fn=self.activation_fn)
self.shared_net = nn.Sequential(*shared_net).to(self.device)
self.actor_net = nn.Linear(self.net_arch[-1], self.action_dim)
self.value_net = nn.Linear(self.net_arch[-1], 1)
@ -79,18 +34,19 @@ class PPOPolicy(BasePolicy):
self.optimizer = th.optim.Adam(self.parameters(), lr=learning_rate)
def forward(self, state):
state = th.FloatTensor(state).to(self.device)
latent = self.shared_net(state)
# TODO: initialize pi_mean weights properly
mean_actions = self.actor_net(latent)
action_distribution = Normal(mean_actions, self.log_std)
# Sample from the gaussian
action = action_distribution.rsample()
log_prob = action_distribution.log_prob()
log_prob = action_distribution.log_prob(action)
# entropy = action_distribution.entropy()
value = self.value_net(latent)
return action, value, log_prob
def actor_forward(self):
def actor_forward(self, state):
latent = self.shared_net(state)
# TODO: initialize pi_mean weights properly
mean_actions = self.actor_net(latent)
@ -98,7 +54,7 @@ class PPOPolicy(BasePolicy):
# Sample from the gaussian
action = action_distribution.rsample()
return action
def value_forward(self):
pass

View file

@ -5,10 +5,9 @@ import torch.nn.functional as F
import numpy as np
from torchy_baselines.common.base_class import BaseRLModel
from torchy_baselines.common.utils import set_random_seed
from torchy_baselines.common.evaluation import evaluate_policy
from torchy_baselines.ppo.policies import ActorCriticPolicy
from torchy_baselines.common.replay_buffer import ReplayBuffer
from torchy_baselines.ppo.policies import PPOPolicy
from torchy_baselines.common.replay_buffer import RolloutBuffer
class PPO(BaseRLModel):
@ -16,15 +15,18 @@ class PPO(BaseRLModel):
Implementation of Proximal Policy Optimization (PPO) (clip version)
Paper: https://arxiv.org/abs/1707.06347
Code: https://github.com/openai/spinningup/
and https://github.com/ikostrikov/pytorch-a2c-ppo-acktr-gail
and stable_baselines
"""
def __init__(self, policy, env, policy_kwargs=None, verbose=0,
learning_rate=1e-3, seed=0, device='auto',
n_optim=5, batch_size=100, n_steps=256,
gamma=0.99, lambda_=0.95,
_init_setup_model=True):
n_optim=5, batch_size=64, n_steps=256,
gamma=0.99, lambda_=0.95, clip_range=0.2,
ent_coef=0.01, vf_coef=0.5,
_init_setup_model=True):
super(PPO, self).__init__(policy, env, ActorCriticPolicy, policy_kwargs, verbose, device)
super(PPO, self).__init__(policy, env, PPOPolicy, policy_kwargs, verbose, device)
self.max_action = np.abs(self.action_space.high)
self.learning_rate = learning_rate
@ -34,7 +36,10 @@ class PPO(BaseRLModel):
self.n_steps = n_steps
self.gamma = gamma
self.lambda_ = lambda_
self.buffer_rollouts = None
self.clip_range = clip_range
self.ent_coef = ent_coef
self.vf_coef = vf_coef
self.rollout_buffer = None
if _init_setup_model:
self._setup_model()
@ -43,10 +48,11 @@ class PPO(BaseRLModel):
state_dim, action_dim = self.observation_space.shape[0], self.action_space.shape[0]
self.seed(self._seed)
self.rollout_buffer = RolloutBuffer(self.n_steps, state_dim, action_dim, self.device,
gamma=self.gamma, lambda_=self.lambda_)
self.policy = self.policy(self.observation_space, self.action_space,
self.learning_rate, device=self.device, **self.policy_kwargs)
def select_action(self, observation):
# Normally not needed
observation = np.array(observation)
@ -66,52 +72,80 @@ class PPO(BaseRLModel):
"""
return np.clip(self.select_action(observation), -self.max_action, self.max_action)
def collect_rollouts(self, env, rollout_buffer, n_rollout_steps=256, callback=None,
obs=None):
def train_actor(self, n_iterations=1, batch_size=100, tau_actor=0.005, tau_critic=0.005, replay_data=None):
n_steps = 0
done = obs is None
rollout_buffer.reset()
while n_steps < n_rollout_steps:
# Reset environment
if done:
obs = env.reset()
# No grad ok?
with th.no_grad():
action, value, log_prob = self.policy.forward(obs)
action = action[0].detach().cpu().numpy()
# Rescale and perform action
new_obs, reward, done, _ = env.step(np.clip(action, -self.max_action, self.max_action))
n_steps += 1
rollout_buffer.add(obs, new_obs, action, reward, float(done), value, log_prob)
obs = new_obs
if done:
value = 0.0
obs = None
rollout_buffer.finish_path(last_value=value)
return obs
def train(self, n_iterations, batch_size=64):
# TODO: replace with iterator?
for it in range(n_iterations):
# Sample replay buffer
if replay_data is None:
state, action, next_state, done, reward = self.replay_buffer.sample(batch_size)
else:
state, action, next_state, done, reward = replay_data
replay_data = self.rollout_buffer.sample(batch_size)
state, action, next_state, done, reward, _, old_log_prob, advantage, return_batch = replay_data
# Compute actor loss
actor_loss = -self.critic.q1_forward(state, self.actor(state)).mean()
_, value, log_prob = self.policy.forward(state)
# Optimize the actor
self.actor.optimizer.zero_grad()
actor_loss.backward()
self.actor.optimizer.step()
# Normalize advantage
# advs = returns - values
advantage = (advantage - advantage.mean()) / (advantage.std() + 1e-8)
# Update the frozen target models
if tau_critic > 0:
for param, target_param in zip(self.critic.parameters(), self.critic_target.parameters()):
target_param.data.copy_(tau_critic * param.data + (1 - tau_critic) * target_param.data)
for param, target_param in zip(self.actor.parameters(), self.actor_target.parameters()):
target_param.data.copy_(tau_actor * param.data + (1 - tau_actor) * target_param.data)
def train(self, n_iterations, batch_size=100, discount=0.99,
tau=0.005, policy_noise=0.2, noise_clip=0.5, policy_freq=2):
for it in range(n_iterations):
# Sample replay buffer
replay_data = self.replay_buffer.sample(batch_size)
self.train_critic(replay_data=replay_data)
# Delayed policy updates
if it % policy_freq == 0:
self.train_actor(replay_data=replay_data)
ratio = th.exp(log_prob - old_log_prob)
policy_loss_1 = -advantage * ratio
policy_loss_2 = -advantage * th.clamp(ratio, 1 - self.clip_range, 1 + self.clip_range)
policy_loss = -th.min(policy_loss_1, policy_loss_2).mean()
# value_loss = th.mean((returns - value)**2)
value_loss = F.mse_loss(return_batch, value)
# Approximate entropy
# TODO: replace by distribution entropy
entropy_loss = th.mean(-log_prob)
loss = policy_loss + self.ent_coef * entropy_loss + self.vf_coef * value_loss
# TODO: check kl div
# approx_kl_div = th.mean(old_log_prob - log_prob)
# Optimization step
self.policy.optimizer.zero_grad()
loss.backward()
# TODO: clip grad norm?
# nn.utils.clip_grad_norm_(self.policy.parameters(), self.max_grad_norm)
self.policy.optimizer.step()
def learn(self, total_timesteps, callback=None, log_interval=100,
eval_freq=-1, n_eval_episodes=5, tb_log_name="TD3", reset_num_timesteps=True):
eval_freq=-1, n_eval_episodes=5, tb_log_name="PPO", reset_num_timesteps=True):
timesteps_since_eval = 0
episode_num = 0
evaluations = []
start_time = time.time()
obs = None
while self.num_timesteps < total_timesteps:
@ -120,21 +154,13 @@ class PPO(BaseRLModel):
if callback(locals(), globals()) is False:
break
episode_reward, episode_timesteps = self.collect_rollouts(self.env, n_episodes=1,
action_noise_std=self.action_noise_std,
deterministic=False, callback=None,
start_timesteps=self.start_timesteps,
num_timesteps=self.num_timesteps,
replay_buffer=self.buffer_rollouts)
obs = self.collect_rollouts(self.env, self.rollout_buffer, n_rollout_steps=self.n_steps,
obs=obs)
episode_num += 1
self.num_timesteps += episode_timesteps
timesteps_since_eval += episode_timesteps
self.num_timesteps += self.n_steps
timesteps_since_eval += self.n_steps
if self.num_timesteps > 0:
if self.verbose > 1:
print("Total T: {} Episode Num: {} Episode T: {} Reward: {}".format(
self.num_timesteps, episode_num, episode_timesteps, episode_reward))
self.train(episode_timesteps, batch_size=self.batch_size, policy_freq=self.policy_freq)
self.train(self.n_optim, batch_size=self.batch_size)
# Evaluate episode
if 0 < eval_freq <= timesteps_since_eval:
@ -158,33 +184,3 @@ class PPO(BaseRLModel):
if env is not None:
pass
self.policy.load_state_dict(th.load(path))
class PPOBuffer(ReplayBuffer):
"""docstring for PPOBuffer."""
def __init__(self, buffer_size, state_dim, action_dim, device='cpu',
lambda=0.95):
super(PPOBuffer, self).__init__(buffer_size, state_dim, action_dim, device)
self.returns = th.zeros(self.buffer_size, 1)
self.values = th.zeros(self.buffer_size, 1)
self.log_probs = th.zeros(self.buffer_size, 1)
self.advantages = th.zeros(self.buffer_size, 1)
def compute_gae(self):
"""
From https://github.com/openai/spinningup/blob/master/spinup/algos/ppo/ppo.py
"""
path_slice = slice(self.path_start_idx, self.pos)
rews = np.append(self.rewards[path_slice], last_val)
vals = np.append(self.val_buf[path_slice], last_val)
# the next two lines implement GAE-Lambda advantage calculation
deltas = rews[:-1] + self.gamma * vals[1:] - vals[:-1]
self.advantages[path_slice] = core.discount_cumsum(deltas, self.gamma * self.lam)
# the next line computes rewards-to-go, to be targets for the value function
self.ret_buf[path_slice] = core.discount_cumsum(rews, self.gamma)[:-1]
self.path_start_idx = self.pos