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2026-07-13 13:17:40 +08:00

126 lines
4.5 KiB
Python

import numpy as np
from gymnasium.spaces import Dict, Discrete, MultiDiscrete, Tuple
from ray.rllib.env.multi_agent_env import ENV_STATE, MultiAgentEnv
class TwoStepGame(MultiAgentEnv):
action_space = Discrete(2)
def __init__(self, env_config):
super().__init__()
self.action_space = Discrete(2)
self.state = None
self.agent_1 = 0
self.agent_2 = 1
# MADDPG emits action logits instead of actual discrete actions
self.actions_are_logits = env_config.get("actions_are_logits", False)
self.one_hot_state_encoding = env_config.get("one_hot_state_encoding", False)
self.with_state = env_config.get("separate_state_space", False)
self._agent_ids = {0, 1}
if not self.one_hot_state_encoding:
self.observation_space = Discrete(6)
self.with_state = False
else:
# Each agent gets the full state (one-hot encoding of which of the
# three states are active) as input with the receiving agent's
# ID (1 or 2) concatenated onto the end.
if self.with_state:
self.observation_space = Dict(
{
"obs": MultiDiscrete([2, 2, 2, 3]),
ENV_STATE: MultiDiscrete([2, 2, 2]),
}
)
else:
self.observation_space = MultiDiscrete([2, 2, 2, 3])
def reset(self, *, seed=None, options=None):
if seed is not None:
np.random.seed(seed)
self.state = np.array([1, 0, 0])
return self._obs(), {}
def step(self, action_dict):
if self.actions_are_logits:
action_dict = {
k: np.random.choice([0, 1], p=v) for k, v in action_dict.items()
}
state_index = np.flatnonzero(self.state)
if state_index == 0:
action = action_dict[self.agent_1]
assert action in [0, 1], action
if action == 0:
self.state = np.array([0, 1, 0])
else:
self.state = np.array([0, 0, 1])
global_rew = 0
terminated = False
elif state_index == 1:
global_rew = 7
terminated = True
else:
if action_dict[self.agent_1] == 0 and action_dict[self.agent_2] == 0:
global_rew = 0
elif action_dict[self.agent_1] == 1 and action_dict[self.agent_2] == 1:
global_rew = 8
else:
global_rew = 1
terminated = True
rewards = {self.agent_1: global_rew / 2.0, self.agent_2: global_rew / 2.0}
obs = self._obs()
terminateds = {"__all__": terminated}
truncateds = {"__all__": False}
infos = {
self.agent_1: {"done": terminateds["__all__"]},
self.agent_2: {"done": terminateds["__all__"]},
}
return obs, rewards, terminateds, truncateds, infos
def _obs(self):
if self.with_state:
return {
self.agent_1: {"obs": self.agent_1_obs(), ENV_STATE: self.state},
self.agent_2: {"obs": self.agent_2_obs(), ENV_STATE: self.state},
}
else:
return {self.agent_1: self.agent_1_obs(), self.agent_2: self.agent_2_obs()}
def agent_1_obs(self):
if self.one_hot_state_encoding:
return np.concatenate([self.state, [1]])
else:
return np.flatnonzero(self.state)[0]
def agent_2_obs(self):
if self.one_hot_state_encoding:
return np.concatenate([self.state, [2]])
else:
return np.flatnonzero(self.state)[0] + 3
class TwoStepGameWithGroupedAgents(MultiAgentEnv):
def __init__(self, env_config):
self._agent_ids = {"agents"}
super().__init__()
env = TwoStepGame(env_config)
tuple_obs_space = Tuple([env.observation_space, env.observation_space])
tuple_act_space = Tuple([env.action_space, env.action_space])
self.env = env.with_agent_groups(
groups={"agents": [0, 1]},
obs_space=tuple_obs_space,
act_space=tuple_act_space,
)
self.observation_space = Dict({"agents": self.env.observation_space})
self.action_space = Dict({"agents": self.env.action_space})
def reset(self, *, seed=None, options=None):
return self.env.reset(seed=seed, options=options)
def step(self, actions):
return self.env.step(actions)