File size: 4,943 Bytes
079c32c
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
from typing import Any, Union, Optional
import gym
import torch
import numpy as np
from ding.envs import BaseEnv, BaseEnvTimestep
from ding.envs.common.common_function import affine_transform
from ding.utils import ENV_REGISTRY
from ding.torch_utils import to_ndarray, to_list


@ENV_REGISTRY.register('pendulum')
class PendulumEnv(BaseEnv):

    def __init__(self, cfg: dict) -> None:
        self._cfg = cfg
        self._act_scale = cfg.act_scale
        self._env = gym.make('Pendulum-v1')
        self._init_flag = False
        self._replay_path = None
        if 'continuous' in cfg.keys():
            self._continuous = cfg.continuous
        else:
            self._continuous = True
        self._observation_space = gym.spaces.Box(
            low=np.array([-1.0, -1.0, -8.0]), high=np.array([1.0, 1.0, 8.0]), shape=(3, ), dtype=np.float32
        )
        if self._continuous:
            self._action_space = gym.spaces.Box(low=-2.0, high=2.0, shape=(1, ), dtype=np.float32)
        else:
            self._discrete_action_num = 11
            self._action_space = gym.spaces.Discrete(self._discrete_action_num)
        self._action_space.seed(0)  # default seed
        self._reward_space = gym.spaces.Box(
            low=-1 * (3.14 * 3.14 + 0.1 * 8 * 8 + 0.001 * 2 * 2), high=0.0, shape=(1, ), dtype=np.float32
        )

    def reset(self) -> np.ndarray:
        if not self._init_flag:
            self._env = gym.make('Pendulum-v1')
            if self._replay_path is not None:
                self._env = gym.wrappers.RecordVideo(
                    self._env,
                    video_folder=self._replay_path,
                    episode_trigger=lambda episode_id: True,
                    name_prefix='rl-video-{}'.format(id(self))
                )
            self._init_flag = True
        if hasattr(self, '_seed') and hasattr(self, '_dynamic_seed') and self._dynamic_seed:
            np_seed = 100 * np.random.randint(1, 1000)
            self._env.seed(self._seed + np_seed)
            self._action_space.seed(self._seed + np_seed)
        elif hasattr(self, '_seed'):
            self._env.seed(self._seed)
            self._action_space.seed(self._seed)
        obs = self._env.reset()
        obs = to_ndarray(obs).astype(np.float32)
        self._eval_episode_return = 0.
        return obs

    def close(self) -> None:
        if self._init_flag:
            self._env.close()
        self._init_flag = False

    def seed(self, seed: int, dynamic_seed: bool = True) -> None:
        self._seed = seed
        self._dynamic_seed = dynamic_seed
        np.random.seed(self._seed)

    def step(self, action: np.ndarray) -> BaseEnvTimestep:
        assert isinstance(action, np.ndarray), type(action)
        # if require discrete env, convert actions to [-1 ~ 1] float actions
        if not self._continuous:
            action = (action / (self._discrete_action_num - 1)) * 2 - 1
        # scale into [-2, 2]
        if self._act_scale:
            action = affine_transform(action, min_val=self._env.action_space.low, max_val=self._env.action_space.high)
        obs, rew, done, info = self._env.step(action)
        self._eval_episode_return += rew
        obs = to_ndarray(obs).astype(np.float32)
        # wrapped to be transfered to a array with shape (1,)
        rew = to_ndarray([rew]).astype(np.float32)
        if done:
            info['eval_episode_return'] = self._eval_episode_return
        return BaseEnvTimestep(obs, rew, done, info)

    def enable_save_replay(self, replay_path: Optional[str] = None) -> None:
        if replay_path is None:
            replay_path = './video'
        self._replay_path = replay_path

    def random_action(self) -> np.ndarray:
        # consider discrete
        if self._continuous:
            random_action = self.action_space.sample().astype(np.float32)
        else:
            random_action = self.action_space.sample()
            random_action = to_ndarray([random_action], dtype=np.int64)
        return random_action

    @property
    def observation_space(self) -> gym.spaces.Space:
        return self._observation_space

    @property
    def action_space(self) -> gym.spaces.Space:
        return self._action_space

    @property
    def reward_space(self) -> gym.spaces.Space:
        return self._reward_space

    def __repr__(self) -> str:
        return "DI-engine Pendulum Env({})".format(self._cfg.env_id)


@ENV_REGISTRY.register('mbpendulum')
class MBPendulumEnv(PendulumEnv):

    def termination_fn(self, next_obs: torch.Tensor) -> torch.Tensor:
        """
        Overview:
            This function determines whether each state is a terminated state
        .. note::
            Done is always false for pendulum, according to\
            <https://github.com/openai/gym/blob/master/gym/envs/classic_control/pendulum.py>.
        """
        done = torch.zeros_like(next_obs.sum(-1)).bool()
        return done