def __init__(self, num_actions: int):
super().__init__(name='impala_atari_network')
self._embed = embedding.OAREmbedding(
DeepAtariTorso(use_layer_norm=True), num_actions)
self._core = hk.GRU(256)
self._head = policy_value.PolicyValueHead(num_actions)
self._num_actions = num_actions
def network(inputs: List[jnp.ndarray], state) -> ModelOutput:
observation = hk.Flatten()(inputs[0]).reshape((1, -1))
previous_reward = inputs[1].reshape((1, 1))
previous_action = inputs[2].reshape((1, -1))
torso = hk.nets.MLP(encoding_hidden_size)
gru = hk.GRU(rnn_hidden_size)
policy_head = hk.Linear(action_spec.num_values)
value_head = hk.Linear(1)
input_embedding = jnp.concatenate(
[observation, previous_reward, previous_action], -1)
input_embedding = torso(input_embedding)
embedding, state = gru(input_embedding, state)
logits = policy_head(embedding)
value = value_head(embedding)
return (logits, jnp.squeeze(value, axis=-1), embedding, embedding,
embedding), state
def make_flexible_recurrent_net(core_type: str,
net_type: str,
output_dims: int,
num_units: Union[Sequence[int], int],
num_layers: Optional[int],
activation: Activation,
activate_final: bool = False,
name: Optional[str] = None,
**unused_kwargs):
"""Commonly used for creating a flexible recurrences."""
if net_type != "mlp":
raise ValueError("We do not support convolutional recurrent nets atm.")
if unused_kwargs:
logging.warning("Unused kwargs of `make_flexible_recurrent_net`: %s",
str(unused_kwargs))
if isinstance(num_units, (list, tuple)):
num_units = list(num_units) + [output_dims]
num_layers = len(num_units)
else:
assert num_layers is not None
num_units = [num_units] * (num_layers - 1) + [output_dims]
name = name or f"{core_type.upper()}"
activation = utils.get_activation(activation)
core_list = []
for i, n in enumerate(num_units):
if core_type.lower() == "vanilla":
core_list.append(hk.VanillaRNN(hidden_size=n, name=f"{name}_{i}"))
elif core_type.lower() == "lstm":
core_list.append(hk.LSTM(hidden_size=n, name=f"{name}_{i}"))
elif core_type.lower() == "gru":
core_list.append(hk.GRU(hidden_size=n, name=f"{name}_{i}"))
else:
raise ValueError(f"Unrecognized core_type={core_type}.")
if i != num_layers - 1:
core_list.append(activation)
if activate_final:
core_list.append(activation)
return hk.DeepRNN(core_list, name="RNN")
def __call__(self, inputs, state):
batch_size = inputs.shape[0]
resets = np.broadcast_to(True, (batch_size,))
return self.wrapped((inputs, resets), state)
# RNN cores. For shape, use the shape of a single example.
RNN_CORES = (
ModuleDescriptor(
name="ResetCore",
create=lambda: ResetCoreAdapter(hk.ResetCore(DummyCore())),
shape=(BATCH_SIZE, 128)),
ModuleDescriptor(
name="GRU",
create=lambda: hk.GRU(1),
shape=(BATCH_SIZE, 128)),
ModuleDescriptor(
name="IdentityCore",
create=lambda: hk.IdentityCore(),
shape=(BATCH_SIZE, 128)),
ModuleDescriptor(
name="LSTM",
create=lambda: hk.LSTM(1),
shape=(BATCH_SIZE, 128)),
ModuleDescriptor(
name="Conv1DLSTM",
create=lambda: hk.Conv1DLSTM([2], 3, 3),
shape=(BATCH_SIZE, 2, 2)),
ModuleDescriptor(
name="Conv2DLSTM",
