class minari.StepDataCallback[source]#

Callback to create step data dictionary from the return data of each Gymnasium environment step.

This callback can be overridden to add extra environment information in each step or edit the observation, action, reward, termination, truncation, or info returns.


minari.StepDataCallback.__call__(self, env: Env, obs: Any, info: Dict[str, Any], action: Any | None = None, rew: Any | None = None, terminated: bool | None = None, truncated: bool | None = None) StepData#

Callback method.

The input arguments belong to a Gymnasium stepping transition: obs, rew, terminated, truncated, info = env.step(action). Override this method to add additional keys or edit each environment’s step returns. Additional nested dictionaries can be added to the returned step dictionary as follows:

class CustomStepDataCallback(StepDataCallback):
    def __call__(self, env, **kwargs):
        step_data = super().__call__(env, **kwargs)
        step_data['environment_states'] = {}
        step_data['environment_states']['pose'] = {}
        step_data['environment_states']['pose']['position'] = env.position
        step_data['environment_states']['pose']['orientation'] = env.orientation
        step_data['environment_states']['velocity'] = env.velocity

        return step_data

The Minari dataset will contain a dictionary called environment_states with velocity value and another dictionary pose with position and orientation

  • env (gym.Env) – current Gymnasium environment.

  • obs (Any) – observation returned by env.step(action)

  • info (Dict) – information dictionary returned by env.step(action)

  • action (Optional[Any], optional) – stepping action in env.step(action). Defaults to None.

  • rew (Optional[Any], optional) – reward returned by env.step(action). Defaults to None.

  • terminated (Optional[Any], optional) – terminated returned by env.step(action). Defaults to None.

  • truncated (Optional[Any], optional) – truncated returned by env.step(action). Defaults to None.


Dict – dictionary step data. Must contain the keys in STEP_DATA_KEYS = {‘actions’, ‘observations’, ‘rewards’, ‘terminations’, ‘truncations’, ‘infos’}. Additional key’s can be added with nested dictionaries