Tianshou/test/discrete/test_sac.py
2021-04-16 20:37:12 +08:00

128 lines
5.4 KiB
Python

import os
import gym
import torch
import pprint
import argparse
import numpy as np
from torch.utils.tensorboard import SummaryWriter
from tianshou.utils import BasicLogger
from tianshou.env import SubprocVectorEnv
from tianshou.utils.net.common import Net
from tianshou.policy import DiscreteSACPolicy
from tianshou.trainer import offpolicy_trainer
from tianshou.utils.net.discrete import Actor, Critic
from tianshou.data import Collector, VectorReplayBuffer
def get_args():
parser = argparse.ArgumentParser()
parser.add_argument('--task', type=str, default='CartPole-v0')
parser.add_argument('--seed', type=int, default=1626)
parser.add_argument('--buffer-size', type=int, default=20000)
parser.add_argument('--actor-lr', type=float, default=1e-4)
parser.add_argument('--critic-lr', type=float, default=1e-3)
parser.add_argument('--alpha-lr', type=float, default=3e-4)
parser.add_argument('--gamma', type=float, default=0.95)
parser.add_argument('--tau', type=float, default=0.005)
parser.add_argument('--alpha', type=float, default=0.05)
parser.add_argument('--auto-alpha', action="store_true", default=False)
parser.add_argument('--epoch', type=int, default=5)
parser.add_argument('--step-per-epoch', type=int, default=10000)
parser.add_argument('--step-per-collect', type=int, default=10)
parser.add_argument('--update-per-step', type=float, default=0.1)
parser.add_argument('--batch-size', type=int, default=128)
parser.add_argument('--hidden-sizes', type=int, nargs='*', default=[128, 128])
parser.add_argument('--training-num', type=int, default=10)
parser.add_argument('--test-num', type=int, default=100)
parser.add_argument('--logdir', type=str, default='log')
parser.add_argument('--render', type=float, default=0.0)
parser.add_argument('--rew-norm', action="store_true", default=False)
parser.add_argument('--n-step', type=int, default=3)
parser.add_argument(
'--device', type=str,
default='cuda' if torch.cuda.is_available() else 'cpu')
args = parser.parse_known_args()[0]
return args
def test_discrete_sac(args=get_args()):
env = gym.make(args.task)
args.state_shape = env.observation_space.shape or env.observation_space.n
args.action_shape = env.action_space.shape or env.action_space.n
train_envs = SubprocVectorEnv(
[lambda: gym.make(args.task) for _ in range(args.training_num)])
test_envs = SubprocVectorEnv(
[lambda: gym.make(args.task) for _ in range(args.test_num)])
# seed
np.random.seed(args.seed)
torch.manual_seed(args.seed)
train_envs.seed(args.seed)
test_envs.seed(args.seed)
# model
net = Net(args.state_shape, hidden_sizes=args.hidden_sizes,
device=args.device)
actor = Actor(net, args.action_shape,
softmax_output=False, device=args.device).to(args.device)
actor_optim = torch.optim.Adam(actor.parameters(), lr=args.actor_lr)
net_c1 = Net(args.state_shape, hidden_sizes=args.hidden_sizes,
device=args.device)
critic1 = Critic(net_c1, last_size=args.action_shape,
device=args.device).to(args.device)
critic1_optim = torch.optim.Adam(critic1.parameters(), lr=args.critic_lr)
net_c2 = Net(args.state_shape, hidden_sizes=args.hidden_sizes,
device=args.device)
critic2 = Critic(net_c2, last_size=args.action_shape,
device=args.device).to(args.device)
critic2_optim = torch.optim.Adam(critic2.parameters(), lr=args.critic_lr)
# better not to use auto alpha in CartPole
if args.auto_alpha:
target_entropy = 0.98 * np.log(np.prod(args.action_shape))
log_alpha = torch.zeros(1, requires_grad=True, device=args.device)
alpha_optim = torch.optim.Adam([log_alpha], lr=args.alpha_lr)
args.alpha = (target_entropy, log_alpha, alpha_optim)
policy = DiscreteSACPolicy(
actor, actor_optim, critic1, critic1_optim, critic2, critic2_optim,
args.tau, args.gamma, args.alpha, estimation_step=args.n_step,
reward_normalization=args.rew_norm)
# collector
train_collector = Collector(
policy, train_envs,
VectorReplayBuffer(args.buffer_size, len(train_envs)))
test_collector = Collector(policy, test_envs)
# train_collector.collect(n_step=args.buffer_size)
# log
log_path = os.path.join(args.logdir, args.task, 'discrete_sac')
writer = SummaryWriter(log_path)
logger = BasicLogger(writer)
def save_fn(policy):
torch.save(policy.state_dict(), os.path.join(log_path, 'policy.pth'))
def stop_fn(mean_rewards):
return mean_rewards >= env.spec.reward_threshold
# trainer
result = offpolicy_trainer(
policy, train_collector, test_collector, args.epoch,
args.step_per_epoch, args.step_per_collect, args.test_num,
args.batch_size, stop_fn=stop_fn, save_fn=save_fn, logger=logger,
update_per_step=args.update_per_step, test_in_train=False)
assert stop_fn(result['best_reward'])
if __name__ == '__main__':
pprint.pprint(result)
# Let's watch its performance!
env = gym.make(args.task)
policy.eval()
collector = Collector(policy, env)
result = collector.collect(n_episode=1, render=args.render)
rews, lens = result["rews"], result["lens"]
print(f"Final reward: {rews.mean()}, length: {lens.mean()}")
if __name__ == '__main__':
test_discrete_sac()