Module `pearl.api.environment`

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from __future__ import annotations

from abc import ABC, abstractmethod
from typing import Optional, Tuple

from pearl.api.action import Action
from pearl.api.action_result import ActionResult
from pearl.api.action_space import ActionSpace
from pearl.api.observation import Observation


class Environment(ABC):
    """An abstract interface for environments. An `Environment` is an object
    that the agent interacts with and provides the agent with observations in
    the form of an `ActionResult` object. This interface follows the design of
    environments in Gymnasium.
    """

    @property
    @abstractmethod
    def action_space(self) -> ActionSpace:
        """Returns the action space of the environment."""
        pass

    # FIXME: add this and in implement in all concrete subclasses
    # @property
    # @abstractmethod
    # def observation_space(self) -> Space:
    #     """Returns the observation space of the environment."""
    #     pass

    @abstractmethod
    def reset(self, seed: Optional[int] = None) -> Tuple[Observation, ActionSpace]:
        """Resets the environment and returns the initial observation and
        initial available action space."""
        pass

    @abstractmethod
    def step(self, action: Action) -> ActionResult:
        """Takes one step in the environment given the agent's action. Returns an
        `ActionResult` object containing the next observation, reward, and done flag."""
        pass

    def render(self) -> None:
        """Renders the environment. Default implementation does nothing."""
        return None

    def close(self) -> None:
        """
        Closes environment, taking care of any cleanup needed.
        Default implementation does nothing.
        """
        return None

Classes

class Environment

An abstract interface for environments. An Environment is an object that the agent interacts with and provides the agent with observations in the form of an ActionResult object. This interface follows the design of environments in Gymnasium.

Expand source code

class Environment(ABC):
    """An abstract interface for environments. An `Environment` is an object
    that the agent interacts with and provides the agent with observations in
    the form of an `ActionResult` object. This interface follows the design of
    environments in Gymnasium.
    """

    @property
    @abstractmethod
    def action_space(self) -> ActionSpace:
        """Returns the action space of the environment."""
        pass

    # FIXME: add this and in implement in all concrete subclasses
    # @property
    # @abstractmethod
    # def observation_space(self) -> Space:
    #     """Returns the observation space of the environment."""
    #     pass

    @abstractmethod
    def reset(self, seed: Optional[int] = None) -> Tuple[Observation, ActionSpace]:
        """Resets the environment and returns the initial observation and
        initial available action space."""
        pass

    @abstractmethod
    def step(self, action: Action) -> ActionResult:
        """Takes one step in the environment given the agent's action. Returns an
        `ActionResult` object containing the next observation, reward, and done flag."""
        pass

    def render(self) -> None:
        """Renders the environment. Default implementation does nothing."""
        return None

    def close(self) -> None:
        """
        Closes environment, taking care of any cleanup needed.
        Default implementation does nothing.
        """
        return None

Ancestors

abc.ABC

Subclasses

Instance variables

var action_space : ActionSpace

Returns the action space of the environment.

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@property
@abstractmethod
def action_space(self) -> ActionSpace:
    """Returns the action space of the environment."""
    pass

Methods

def close(self) ‑> None

Closes environment, taking care of any cleanup needed. Default implementation does nothing.

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def close(self) -> None:
    """
    Closes environment, taking care of any cleanup needed.
    Default implementation does nothing.
    """
    return None

def render(self) ‑> None

Renders the environment. Default implementation does nothing.

Expand source code

def render(self) -> None:
    """Renders the environment. Default implementation does nothing."""
    return None

def reset(self, seed: Optional[int] = None) ‑> Tuple[object, ActionSpace]

Resets the environment and returns the initial observation and initial available action space.

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@abstractmethod
def reset(self, seed: Optional[int] = None) -> Tuple[Observation, ActionSpace]:
    """Resets the environment and returns the initial observation and
    initial available action space."""
    pass

def step(self, action: Action) ‑> ActionResult

Takes one step in the environment given the agent's action. Returns an ActionResult object containing the next observation, reward, and done flag.

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@abstractmethod
def step(self, action: Action) -> ActionResult:
    """Takes one step in the environment given the agent's action. Returns an
    `ActionResult` object containing the next observation, reward, and done flag."""
    pass