garage.envs.wrappers.stack_frames
¶
Stack frames wrapper for gym.Env.
- class StackFrames(env, n_frames, axis=2)¶
Bases:
gym.Wrapper
gym.Env wrapper to stack multiple frames.
Useful for training feed-forward agents on dynamic games. Only works with gym.spaces.Box environment with 2D single channel frames.
- Parameters
- Raises
ValueError – If observation space shape is not 2 dimnesional,
if the environment is not gym.spaces.Box, or if the specified axis –
is not 0 or 2. –
- property observation_space¶
gym.Env observation space.
- Type
gym.spaces.Box
- property spec¶
- property unwrapped¶
Completely unwrap this env.
- Returns
The base non-wrapped gym.Env instance
- Return type
gym.Env
- metadata¶
- reward_range¶
- action_space¶
- reset()¶
gym.Env reset function.
- Returns
Observation conforming to observation_space float: Reward for this step bool: Termination signal dict: Extra information from the environment.
- Return type
np.ndarray
- step(action)¶
gym.Env step function.
- Parameters
action (int) – index of the action to take.
- Returns
Observation conforming to observation_space float: Reward for this step bool: Termination signal dict: Extra information from the environment.
- Return type
np.ndarray
- classmethod class_name()¶
- render(mode='human', **kwargs)¶
Renders the environment.
The set of supported modes varies per environment. (And some environments do not support rendering at all.) By convention, if mode is:
human: render to the current display or terminal and return nothing. Usually for human consumption.
rgb_array: Return an numpy.ndarray with shape (x, y, 3), representing RGB values for an x-by-y pixel image, suitable for turning into a video.
ansi: Return a string (str) or StringIO.StringIO containing a terminal-style text representation. The text can include newlines and ANSI escape sequences (e.g. for colors).
Note
- Make sure that your class’s metadata ‘render.modes’ key includes
the list of supported modes. It’s recommended to call super() in implementations to use the functionality of this method.
- Parameters
mode (str) – the mode to render with
Example:
- class MyEnv(Env):
metadata = {‘render.modes’: [‘human’, ‘rgb_array’]}
- def render(self, mode=’human’):
- if mode == ‘rgb_array’:
return np.array(…) # return RGB frame suitable for video
- elif mode == ‘human’:
… # pop up a window and render
- else:
super(MyEnv, self).render(mode=mode) # just raise an exception
- close()¶
Override close in your subclass to perform any necessary cleanup.
Environments will automatically close() themselves when garbage collected or when the program exits.
- seed(seed=None)¶
Sets the seed for this env’s random number generator(s).
Note
Some environments use multiple pseudorandom number generators. We want to capture all such seeds used in order to ensure that there aren’t accidental correlations between multiple generators.
- Returns
- Returns the list of seeds used in this env’s random
number generators. The first value in the list should be the “main” seed, or the value which a reproducer should pass to ‘seed’. Often, the main seed equals the provided ‘seed’, but this won’t be true if seed=None, for example.
- Return type
list<bigint>
- compute_reward(achieved_goal, desired_goal, info)¶