Files
easy-rl/codes/A2C/task0.py
johnjim0816 bd51b5a7ad update codes
2021-12-28 18:46:52 +08:00

139 lines
5.3 KiB
Python

import sys
import os
curr_path = os.path.dirname(os.path.abspath(__file__)) # 当前文件所在绝对路径
parent_path = os.path.dirname(curr_path) # 父路径
sys.path.append(parent_path) # 添加路径到系统路径
import gym
import numpy as np
import torch
import torch.optim as optim
import datetime
from common.multiprocessing_env import SubprocVecEnv
from A2C.agent import ActorCritic
from common.utils import save_results, make_dir
from common.utils import plot_rewards
curr_time = datetime.datetime.now().strftime("%Y%m%d-%H%M%S") # 获取当前时间
algo_name = 'A2C' # 算法名称
env_name = 'CartPole-v0' # 环境名称
class A2CConfig:
def __init__(self) -> None:
self.algo_name = algo_name# 算法名称
self.env_name = env_name # 环境名称
self.n_envs = 8 # 异步的环境数目
self.gamma = 0.99 # 强化学习中的折扣因子
self.hidden_dim = 256
self.lr = 1e-3 # learning rate
self.max_frames = 30000
self.n_steps = 5
self.device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
class PlotConfig:
def __init__(self) -> None:
self.algo_name = algo_name # 算法名称
self.env_name = env_name # 环境名称
self.device = torch.device("cuda" if torch.cuda.is_available() else "cpu") # 检测GPU
self.result_path = curr_path+"/outputs/" + self.env_name + \
'/'+curr_time+'/results/' # 保存结果的路径
self.model_path = curr_path+"/outputs/" + self.env_name + \
'/'+curr_time+'/models/' # 保存模型的路径
self.save = True # 是否保存图片
def make_envs(env_name):
def _thunk():
env = gym.make(env_name)
env.seed(2)
return env
return _thunk
def test_env(env,model,vis=False):
state = env.reset()
if vis: env.render()
done = False
total_reward = 0
while not done:
state = torch.FloatTensor(state).unsqueeze(0).to(cfg.device)
dist, _ = model(state)
next_state, reward, done, _ = env.step(dist.sample().cpu().numpy()[0])
state = next_state
if vis: env.render()
total_reward += reward
return total_reward
def compute_returns(next_value, rewards, masks, gamma=0.99):
R = next_value
returns = []
for step in reversed(range(len(rewards))):
R = rewards[step] + gamma * R * masks[step]
returns.insert(0, R)
return returns
def train(cfg,envs):
print('开始训练!')
print(f'环境:{cfg.env_name}, 算法:{cfg.algo}, 设备:{cfg.device}')
env = gym.make(cfg.env_name) # a single env
env.seed(10)
state_dim = envs.observation_space.shape[0]
action_dim = envs.action_space.n
model = ActorCritic(state_dim, action_dim, cfg.hidden_dim).to(cfg.device)
optimizer = optim.Adam(model.parameters())
frame_idx = 0
test_rewards = []
test_ma_rewards = []
state = envs.reset()
while frame_idx < cfg.max_frames:
log_probs = []
values = []
rewards = []
masks = []
entropy = 0
# rollout trajectory
for _ in range(cfg.n_steps):
state = torch.FloatTensor(state).to(cfg.device)
dist, value = model(state)
action = dist.sample()
next_state, reward, done, _ = envs.step(action.cpu().numpy())
log_prob = dist.log_prob(action)
entropy += dist.entropy().mean()
log_probs.append(log_prob)
values.append(value)
rewards.append(torch.FloatTensor(reward).unsqueeze(1).to(cfg.device))
masks.append(torch.FloatTensor(1 - done).unsqueeze(1).to(cfg.device))
state = next_state
frame_idx += 1
if frame_idx % 100 == 0:
test_reward = np.mean([test_env(env,model) for _ in range(10)])
print(f"frame_idx:{frame_idx}, test_reward:{test_reward}")
test_rewards.append(test_reward)
if test_ma_rewards:
test_ma_rewards.append(0.9*test_ma_rewards[-1]+0.1*test_reward)
else:
test_ma_rewards.append(test_reward)
# plot(frame_idx, test_rewards)
next_state = torch.FloatTensor(next_state).to(cfg.device)
_, next_value = model(next_state)
returns = compute_returns(next_value, rewards, masks)
log_probs = torch.cat(log_probs)
returns = torch.cat(returns).detach()
values = torch.cat(values)
advantage = returns - values
actor_loss = -(log_probs * advantage.detach()).mean()
critic_loss = advantage.pow(2).mean()
loss = actor_loss + 0.5 * critic_loss - 0.001 * entropy
optimizer.zero_grad()
loss.backward()
optimizer.step()
print('完成训练!')
return test_rewards, test_ma_rewards
if __name__ == "__main__":
cfg = A2CConfig()
plot_cfg = PlotConfig()
envs = [make_envs(cfg.env_name) for i in range(cfg.n_envs)]
envs = SubprocVecEnv(envs)
# 训练
rewards,ma_rewards = train(cfg,envs)
make_dir(plot_cfg.result_path,plot_cfg.model_path)
save_results(rewards, ma_rewards, tag='train', path=plot_cfg.result_path) # 保存结果
plot_rewards(rewards, ma_rewards, plot_cfg, tag="train") # 画出结果