ray/rllib/models/tf/fcnet_v2.py

88 lines
3.3 KiB
Python

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import numpy as np
from ray.rllib.models.tf.tf_modelv2 import TFModelV2
from ray.rllib.models.tf.misc import normc_initializer, get_activation_fn
from ray.rllib.utils import try_import_tf
tf = try_import_tf()
class FullyConnectedNetwork(TFModelV2):
"""Generic fully connected network implemented in ModelV2 API."""
def __init__(self, obs_space, action_space, num_outputs, model_config,
name):
super(FullyConnectedNetwork, self).__init__(
obs_space, action_space, num_outputs, model_config, name)
activation = get_activation_fn(model_config.get("fcnet_activation"))
hiddens = model_config.get("fcnet_hiddens")
no_final_linear = model_config.get("no_final_linear")
vf_share_layers = model_config.get("vf_share_layers")
# we are using obs_flat, so take the flattened shape as input
inputs = tf.keras.layers.Input(
shape=(np.product(obs_space.shape), ), name="observations")
last_layer = inputs
i = 1
if no_final_linear:
# the last layer is adjusted to be of size num_outputs
for size in hiddens[:-1]:
last_layer = tf.keras.layers.Dense(
size,
name="fc_{}".format(i),
activation=activation,
kernel_initializer=normc_initializer(1.0))(last_layer)
i += 1
layer_out = tf.keras.layers.Dense(
num_outputs,
name="fc_out",
activation=activation,
kernel_initializer=normc_initializer(1.0))(last_layer)
else:
# the last layer is a linear to size num_outputs
for size in hiddens:
last_layer = tf.keras.layers.Dense(
size,
name="fc_{}".format(i),
activation=activation,
kernel_initializer=normc_initializer(1.0))(last_layer)
i += 1
layer_out = tf.keras.layers.Dense(
num_outputs,
name="fc_out",
activation=None,
kernel_initializer=normc_initializer(0.01))(last_layer)
if not vf_share_layers:
# build a parallel set of hidden layers for the value net
last_layer = inputs
i = 1
for size in hiddens:
last_layer = tf.keras.layers.Dense(
size,
name="fc_value_{}".format(i),
activation=activation,
kernel_initializer=normc_initializer(1.0))(last_layer)
i += 1
value_out = tf.keras.layers.Dense(
1,
name="value_out",
activation=None,
kernel_initializer=normc_initializer(0.01))(last_layer)
self.base_model = tf.keras.Model(inputs, [layer_out, value_out])
self.register_variables(self.base_model.variables)
def forward(self, input_dict, state, seq_lens):
model_out, self._value_out = self.base_model(input_dict["obs_flat"])
return model_out, state
def value_function(self):
return tf.reshape(self._value_out, [-1])