Files
easy-rl/codes/HierarchicalDQN/agent.py
JohnJim0816 b6f63a91bf update
2021-03-31 15:37:09 +08:00

115 lines
5.1 KiB
Python

#!/usr/bin/env python
# coding=utf-8
'''
Author: John
Email: johnjim0816@gmail.com
Date: 2021-03-24 22:18:18
LastEditor: John
LastEditTime: 2021-03-31 14:51:09
Discription:
Environment:
'''
import torch
import torch.nn as nn
import numpy as np
import random,math
import torch.optim as optim
from common.model import MLP
from common.memory import ReplayBuffer
class HierarchicalDQN:
def __init__(self,state_dim,action_dim,cfg):
self.state_dim = state_dim
self.action_dim = action_dim
self.gamma = cfg.gamma
self.device = cfg.device
self.batch_size = cfg.batch_size
self.frame_idx = 0
self.epsilon = lambda frame_idx: cfg.epsilon_end + (cfg.epsilon_start - cfg.epsilon_end ) * math.exp(-1. * frame_idx / cfg.epsilon_decay)
self.policy_net = MLP(2*state_dim, action_dim,cfg.hidden_dim).to(self.device)
self.meta_policy_net = MLP(state_dim, state_dim,cfg.hidden_dim).to(self.device)
self.optimizer = optim.Adam(self.policy_net.parameters(),lr=cfg.lr)
self.meta_optimizer = optim.Adam(self.meta_policy_net.parameters(),lr=cfg.lr)
self.memory = ReplayBuffer(cfg.memory_capacity)
self.meta_memory = ReplayBuffer(cfg.memory_capacity)
self.loss_numpy = 0
self.meta_loss_numpy = 0
self.losses = []
self.meta_losses = []
def to_onehot(self,x):
oh = np.zeros(self.state_dim)
oh[x - 1] = 1.
return oh
def set_goal(self,state):
if random.random() > self.epsilon(self.frame_idx):
with torch.no_grad():
state = torch.tensor(state, device=self.device, dtype=torch.float32).unsqueeze(0)
goal = self.meta_policy_net(state).max(1)[1].item()
else:
goal = random.randrange(self.state_dim)
return goal
def choose_action(self,state):
self.frame_idx += 1
if random.random() > self.epsilon(self.frame_idx):
with torch.no_grad():
state = torch.tensor(state, device=self.device, dtype=torch.float32).unsqueeze(0)
q_value = self.policy_net(state)
action = q_value.max(1)[1].item()
else:
action = random.randrange(self.action_dim)
return action
def update(self):
self.update_policy()
self.update_meta()
def update_policy(self):
if self.batch_size > len(self.memory):
return
state_batch, action_batch, reward_batch, next_state_batch, done_batch = self.memory.sample(self.batch_size)
state_batch = torch.tensor(state_batch,dtype=torch.float)
action_batch = torch.tensor(action_batch,dtype=torch.int64).unsqueeze(1)
reward_batch = torch.tensor(reward_batch,dtype=torch.float)
next_state_batch = torch.tensor(next_state_batch, dtype=torch.float)
done_batch = torch.tensor(np.float32(done_batch))
q_values = self.policy_net(state_batch).gather(dim=1, index=action_batch).squeeze(1)
next_state_values = self.policy_net(next_state_batch).max(1)[0].detach()
expected_q_values = reward_batch + 0.99 * next_state_values * (1-done_batch)
loss = nn.MSELoss()(q_values, expected_q_values)
self.optimizer.zero_grad()
loss.backward()
for param in self.policy_net.parameters(): # clip防止梯度爆炸
param.grad.data.clamp_(-1, 1)
self.optimizer.step()
self.loss_numpy = loss.detach().numpy()
self.losses.append(self.loss_numpy)
def update_meta(self):
if self.batch_size > len(self.meta_memory):
return
state_batch, action_batch, reward_batch, next_state_batch, done_batch = self.meta_memory.sample(self.batch_size)
state_batch = torch.tensor(state_batch,dtype=torch.float)
action_batch = torch.tensor(action_batch,dtype=torch.int64).unsqueeze(1)
reward_batch = torch.tensor(reward_batch,dtype=torch.float)
next_state_batch = torch.tensor(next_state_batch, dtype=torch.float)
done_batch = torch.tensor(np.float32(done_batch))
q_values = self.meta_policy_net(state_batch).gather(dim=1, index=action_batch).squeeze(1)
next_state_values = self.meta_policy_net(next_state_batch).max(1)[0].detach()
expected_q_values = reward_batch + 0.99 * next_state_values * (1-done_batch)
meta_loss = nn.MSELoss()(q_values, expected_q_values)
self.meta_optimizer.zero_grad()
meta_loss.backward()
for param in self.meta_policy_net.parameters(): # clip防止梯度爆炸
param.grad.data.clamp_(-1, 1)
self.meta_optimizer.step()
self.meta_loss_numpy = meta_loss.detach().numpy()
self.meta_losses.append(self.meta_loss_numpy)
def save(self, path):
torch.save(self.policy_net.state_dict(), path+'policy_checkpoint.pth')
torch.save(self.meta_policy_net.state_dict(), path+'meta_checkpoint.pth')
def load(self, path):
self.policy_net.load_state_dict(torch.load(path+'policy_checkpoint.pth'))
self.meta_policy_net.load_state_dict(torch.load(path+'meta_checkpoint.pth'))