add CER sampling and Munchhausen DQN

This commit is contained in:
romue 2021-06-18 13:55:38 +02:00
parent eee4760e72
commit e541e34270

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@ -1,4 +1,4 @@
from typing import NamedTuple, Union
from typing import NamedTuple, Union, Iterable
from collections import namedtuple, deque
import numpy as np
import random
@ -30,8 +30,9 @@ class BaseBuffer:
def add(self, experience):
self.experience.append(experience)
def sample(self, k):
sample = random.choices(self.experience, k=k)
def sample(self, k, cer=4):
sample = random.choices(self.experience, k=k-cer)
for i in range(cer): sample += [self.experience[-i]]
observations = torch.stack([torch.from_numpy(e.observation) for e in sample], 0).float()
next_observations = torch.stack([torch.from_numpy(e.next_observation) for e in sample], 0).float()
actions = torch.tensor([e.action for e in sample]).long()
@ -40,18 +41,6 @@ class BaseBuffer:
return Experience(observations, next_observations, actions, rewards, dones)
class PERBuffer(BaseBuffer):
def __init__(self, size, alpha=0.2):
super(PERBuffer, self).__init__(size)
self.alpha = alpha
def sample(self, k):
pr = [abs(e.priority)**self.alpha for e in self.experience]
pr = np.array(pr) / sum(pr)
idxs = random.choices(range(len(self)), weights=pr, k=k)
pass
class BaseDQN(nn.Module):
def __init__(self):
super(BaseDQN, self).__init__()
@ -80,14 +69,21 @@ class BaseDQN(nn.Module):
return random.randrange(0, 5)
def soft_update(local_model, target_model, tau):
# taken from https://github.com/BY571/Munchausen-RL/blob/master/M-DQN.ipynb
for target_param, local_param in zip(target_model.parameters(), local_model.parameters()):
target_param.data.copy_(tau*local_param.data + (1.-tau)*target_param.data)
class BaseQlearner:
def __init__(self, q_net, target_q_net, env, buffer, target_update, eps_end, n_agents=1,
gamma=0.99, train_every_n_steps=4, n_grad_steps=1,
gamma=0.99, train_every_n_steps=4, n_grad_steps=1, tau=1.0, max_grad_norm=10,
exploration_fraction=0.2, batch_size=64, lr=1e-4, reg_weight=0.0):
self.q_net = q_net
self.target_q_net = target_q_net
self.q_net.apply(self.weights_init)
#self.q_net.apply(self.weights_init)
self.target_q_net.eval()
soft_update(self.q_net, self.target_q_net, tau=1.0)
self.env = env
self.buffer = buffer
self.target_update = target_update
@ -99,10 +95,12 @@ class BaseQlearner:
self.train_every_n_steps = train_every_n_steps
self.n_grad_steps = n_grad_steps
self.lr = lr
self.tau = tau
self.reg_weight = reg_weight
self.n_agents = n_agents
self.device = 'cpu'
self.optimizer = torch.optim.AdamW(self.q_net.parameters(), lr=self.lr)
self.max_grad_norm = max_grad_norm
self.running_reward = deque(maxlen=5)
self.running_loss = deque(maxlen=5)
self._n_updates = 0
@ -112,7 +110,7 @@ class BaseQlearner:
return self
@staticmethod
def weights_init(module, activation='relu'):
def weights_init(module, activation='leaky_relu'):
if isinstance(module, (nn.Linear, nn.Conv2d)):
nn.init.xavier_normal_(module.weight, gain=torch.nn.init.calculate_gain(activation))
if module.bias is not None:
@ -154,35 +152,38 @@ class BaseQlearner:
self._n_updates += 1
if step % self.target_update == 0:
print('UPDATE')
polyak_update(self.q_net.parameters(), self.target_q_net.parameters(), 1)
soft_update(self.q_net, self.target_q_net, tau=self.tau)
self.running_reward.append(total_reward)
if step % 10 == 0:
print(f'Step: {step} ({(step/n_steps)*100:.2f}%)\tRunning reward: {sum(list(self.running_reward))/len(self.running_reward):.2f}\t'
f' eps: {self.eps:.4f}\tRunning loss: {sum(list(self.running_loss))/len(self.running_loss):.4f}\tUpdates:{self._n_updates}')
def _training_routine(self, obs, next_obs, action):
def _training_routine(self, obs, next_obs, action, reward):
current_q_values = self.q_net(obs)
current_q_values = torch.gather(current_q_values, dim=-1, index=action)
next_q_values_raw = self.target_q_net(next_obs).max(dim=-1)[0].reshape(-1, 1).detach()
return current_q_values, next_q_values_raw
def train(self):
if len(self.buffer) < self.batch_size: return
for _ in range(self.n_grad_steps):
experience = self.buffer.sample(self.batch_size)
#print(experience.observation.shape, experience.next_observation.shape, experience.action.shape, experience.reward.shape, experience.done.shape)
experience = self.buffer.sample(self.batch_size, cer=self.train_every_n_steps)
if self.n_agents <= 1:
pred_q, target_q_raw = self._training_routine(experience.observation, experience.next_observation, experience.action)
pred_q, target_q_raw = self._training_routine(experience.observation,
experience.next_observation,
experience.action,
experience.reward)
else:
pred_q, target_q_raw = torch.zeros((self.batch_size, 1)), torch.zeros((self.batch_size, 1))
pred_q, target_q_raw, reward = [torch.zeros((self.batch_size, 1))]*3
for agent_i in range(self.n_agents):
q_values, next_q_values_raw = self._training_routine(experience.observation[:, agent_i],
experience.next_observation[:, agent_i],
experience.action[:, agent_i].unsqueeze(-1)
)
experience.next_observation[:, agent_i],
experience.action[:, agent_i].unsqueeze(-1),
experience.reward)
pred_q += q_values
target_q_raw += next_q_values_raw
target_q = experience.reward + (1 - experience.done) * self.gamma * target_q_raw
@ -193,7 +194,56 @@ class BaseQlearner:
# Optimize the model
self.optimizer.zero_grad()
loss.backward()
torch.nn.utils.clip_grad_norm_(self.q_net.parameters(), 10)
torch.nn.utils.clip_grad_norm_(self.q_net.parameters(), self.max_grad_norm)
self.optimizer.step()
class MDQN(BaseQlearner):
def __init__(self, *args, temperature=0.03, alpha=0.9, clip_l0=-1.0, **kwargs):
super(MDQN, self).__init__(*args, **kwargs)
assert self.n_agents == 1, 'M-DQN currently only supports single agent training'
self.temperature = temperature
self.alpha = alpha
self.clip0 = clip_l0
def train(self):
if len(self.buffer) < self.batch_size: return
for _ in range(self.n_grad_steps):
experience = self.buffer.sample(self.batch_size, cer=self.train_every_n_steps)
q_target_next = self.target_q_net(experience.next_observation).detach()
advantages_next = (q_target_next - q_target_next.max(-1)[0].unsqueeze(-1))
logsum = torch.logsumexp(advantages_next / self.temperature, -1).unsqueeze(-1)
tau_log_pi_next = advantages_next - self.temperature * logsum
pi_target = F.softmax(q_target_next / self.temperature, dim=-1)
q_target = (self.gamma * (pi_target * (q_target_next - tau_log_pi_next) * (1 - experience.done)).sum(-1)).unsqueeze(-1)
q_k_targets = self.target_q_net(experience.observation).detach()
v_k_target = q_k_targets.max(-1)[0].unsqueeze(-1)
logsum = torch.logsumexp((q_k_targets - v_k_target) / self.temperature, -1).unsqueeze(-1)
log_pi = q_k_targets - v_k_target - self.temperature * logsum
munchausen_addon = log_pi.gather(-1, experience.action)
munchausen_reward = (experience.reward + self.alpha * torch.clamp(munchausen_addon, min=self.clip0, max=0))
# Compute Q targets for current states
m_q_target = munchausen_reward + q_target
# Get expected Q values from local model
q_k = self.q_net(experience.observation)
pred_q = q_k.gather(-1, experience.action)
# Compute loss
loss = torch.mean(self.reg_weight * pred_q + torch.pow(pred_q - m_q_target, 2))
# log loss
self.running_loss.append(loss.item())
# Optimize the model
self.optimizer.zero_grad()
loss.backward()
torch.nn.utils.clip_grad_norm_(self.q_net.parameters(), self.max_grad_norm)
self.optimizer.step()
@ -221,6 +271,6 @@ if __name__ == '__main__':
dqn, target_dqn = BaseDQN(), BaseDQN()
learner = BaseQlearner(dqn, target_dqn, env, BaseBuffer(40000), target_update=3500, lr=0.0008, gamma=0.99, n_agents=N_AGENTS,
train_every_n_steps=4, eps_end=0.05, n_grad_steps=1, reg_weight=0.05, exploration_fraction=0.25, batch_size=64)
learner = MDQN(dqn, target_dqn, env, BaseBuffer(40000), target_update=3500, lr=0.0008, gamma=0.99, n_agents=N_AGENTS, tau=0.95, max_grad_norm=10,
train_every_n_steps=4, eps_end=0.025, n_grad_steps=1, reg_weight=0.1, exploration_fraction=0.25, batch_size=64)
learner.learn(100000)