def __init__(
self,
stack_size,
replay_capacity,
batch_size,
update_horizon=1,
gamma=0.99,
max_sample_attempts=1000,
):
"""Initializes PrioritizedReplayBuffer.
Args:
stack_size: int, number of frames to use in state stack.
replay_capacity: int, number of transitions to keep in memory.
batch_size: int.
update_horizon: int, length of update ('n' in n-step update).
gamma: int, the discount factor.
"""
super(PrioritizedReplayBuffer, self).__init__(
stack_size=stack_size,
replay_capacity=replay_capacity,
batch_size=batch_size,
update_horizon=update_horizon,
gamma=gamma,
)
self._max_sample_attempts = max_sample_attempts
self.sum_tree = sum_tree.SumTree(replay_capacity)
def __init__(
self,
observation_shape,
stack_size,
replay_capacity,
batch_size,
update_horizon=1,
gamma=0.99,
max_sample_attempts=1000,
extra_storage_types=None,
observation_dtype=np.uint8,
terminal_dtype=np.uint8,
action_shape=(),
action_dtype=np.int32,
reward_shape=(),
reward_dtype=np.float32,
):
"""Initializes PrioritizedReplayBuffer.
Args:
observation_shape: tuple of ints.
stack_size: int, number of frames to use in state stack.
replay_capacity: int, number of transitions to keep in memory.
batch_size: int.
update_horizon: int, length of update ('n' in n-step update).
gamma: int, the discount factor.
max_sample_attempts: int, the maximum number of attempts allowed to
get a sample.
extra_storage_types: list of ReplayElements defining the type of the extra
contents that will be stored and returned by sample_transition_batch.
observation_dtype: np.dtype, type of the observations. Defaults to
np.uint8 for Atari 2600.
terminal_dtype: np.dtype, type of the terminals. Defaults to np.uint8 for
Atari 2600.
action_shape: tuple of ints, the shape for the action vector. Empty tuple
means the action is a scalar.
action_dtype: np.dtype, type of elements in the action.
reward_shape: tuple of ints, the shape of the reward vector. Empty tuple
means the reward is a scalar.
reward_dtype: np.dtype, type of elements in the reward.
"""
super(PrioritizedReplayBuffer, self).__init__(
observation_shape=observation_shape,
stack_size=stack_size,
replay_capacity=replay_capacity,
batch_size=batch_size,
update_horizon=update_horizon,
gamma=gamma,
max_sample_attempts=max_sample_attempts,
extra_storage_types=extra_storage_types,
observation_dtype=observation_dtype,
terminal_dtype=terminal_dtype,
action_shape=action_shape,
action_dtype=action_dtype,
reward_shape=reward_shape,
reward_dtype=reward_dtype,
)
self.sum_tree = sum_tree.SumTree(replay_capacity)
def testSetValueSmallCapacity(self):
tree = sum_tree.SumTree(capacity=1)
tree.set(0, 1.5)
self.assertEqual(tree.get(0), 1.5)
def testSmallCapacityConstructor(self):
tree = sum_tree.SumTree(capacity=1)
self.assertEqual(len(tree.nodes), 1)
tree = sum_tree.SumTree(capacity=2)
self.assertEqual(len(tree.nodes), 2)
def testNegativeCapacity(self):
with self.assertRaises(
ValueError, msg="Sum tree capacity should be positive. Got: -1"
):
sum_tree.SumTree(capacity=-1)
def setUp(self):
self._tree = sum_tree.SumTree(capacity=100)