Tianshou/test/discrete/test_pg.py
ChenDRAG 7036073649
Trainer refactor : some definition change (#293)
This PR focus on some definition change of trainer to make it more friendly to use and be consistent with typical usage in research papers, typically change `collect-per-step` to `step-per-collect`, add `update-per-step` / `episode-per-collect` accordingly, and modify the documentation.
2021-02-21 13:06:02 +08:00

102 lines
3.9 KiB
Python

import os
import gym
import torch
import pprint
import argparse
import numpy as np
from torch.utils.tensorboard import SummaryWriter
from tianshou.policy import PGPolicy
from tianshou.env import DummyVectorEnv
from tianshou.utils.net.common import Net
from tianshou.trainer import onpolicy_trainer
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=0)
parser.add_argument('--buffer-size', type=int, default=20000)
parser.add_argument('--lr', type=float, default=1e-3)
parser.add_argument('--gamma', type=float, default=0.95)
parser.add_argument('--epoch', type=int, default=10)
parser.add_argument('--step-per-epoch', type=int, default=40000)
parser.add_argument('--episode-per-collect', type=int, default=8)
parser.add_argument('--repeat-per-collect', type=int, default=2)
parser.add_argument('--batch-size', type=int, default=64)
parser.add_argument('--hidden-sizes', type=int,
nargs='*', default=[128, 128, 128, 128])
parser.add_argument('--training-num', type=int, default=8)
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.)
parser.add_argument('--rew-norm', type=int, default=1)
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_pg(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 = gym.make(args.task)
# you can also use tianshou.env.SubprocVectorEnv
train_envs = DummyVectorEnv(
[lambda: gym.make(args.task) for _ in range(args.training_num)])
# test_envs = gym.make(args.task)
test_envs = DummyVectorEnv(
[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, args.action_shape,
hidden_sizes=args.hidden_sizes,
device=args.device, softmax=True).to(args.device)
optim = torch.optim.Adam(net.parameters(), lr=args.lr)
dist = torch.distributions.Categorical
policy = PGPolicy(net, optim, dist, args.gamma,
reward_normalization=args.rew_norm)
# collector
train_collector = Collector(
policy, train_envs,
VectorReplayBuffer(args.buffer_size, len(train_envs)),
exploration_noise=True)
test_collector = Collector(policy, test_envs)
# log
log_path = os.path.join(args.logdir, args.task, 'pg')
writer = SummaryWriter(log_path)
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 = onpolicy_trainer(
policy, train_collector, test_collector, args.epoch,
args.step_per_epoch, args.repeat_per_collect, args.test_num, args.batch_size,
episode_per_collect=args.episode_per_collect, stop_fn=stop_fn, save_fn=save_fn,
writer=writer)
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_pg()