ray/rllib/examples/env/stateless_pendulum.py

35 lines
1.1 KiB
Python

from gym.spaces import Box
import numpy as np
from gym.envs.classic_control import PendulumEnv
class StatelessPendulum(PendulumEnv):
"""Partially observable variant of the Pendulum gym environment.
https://github.com/openai/gym/blob/master/gym/envs/classic_control/
pendulum.py
We delete the angular velocity component of the state, so that it
can only be solved by a memory enhanced model (policy).
"""
def __init__(self, config=None):
config = config or {}
g = config.get("g", 10.0)
super().__init__(g=g)
# Fix our observation-space (remove angular velocity component).
high = np.array([1., 1.], dtype=np.float32)
self.observation_space = Box(low=-high, high=high, dtype=np.float32)
def step(self, action):
next_obs, reward, done, info = super().step(action)
# next_obs is [cos(theta), sin(theta), theta-dot (angular velocity)]
return next_obs[:-1], reward, done, info
def reset(self):
init_obs = super().reset()
# init_obs is [cos(theta), sin(theta), theta-dot (angular velocity)]
return init_obs[:-1]