ray/rllib/examples/custom_keras_model.py

105 lines
3.7 KiB
Python

"""Example of using a custom ModelV2 Keras-style model."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import argparse
import ray
from ray import tune
from ray.rllib.models import ModelCatalog
from ray.rllib.models.tf.misc import normc_initializer
from ray.rllib.models.tf.tf_modelv2 import TFModelV2
from ray.rllib.agents.dqn.distributional_q_model import DistributionalQModel
from ray.rllib.utils import try_import_tf
tf = try_import_tf()
parser = argparse.ArgumentParser()
parser.add_argument("--run", type=str, default="DQN") # Try PG, PPO, DQN
parser.add_argument("--stop", type=int, default=200)
class MyKerasModel(TFModelV2):
"""Custom model for policy gradient algorithms."""
def __init__(self, obs_space, action_space, num_outputs, model_config,
name):
super(MyKerasModel, self).__init__(obs_space, action_space,
num_outputs, model_config, name)
self.inputs = tf.keras.layers.Input(
shape=obs_space.shape, name="observations")
layer_1 = tf.keras.layers.Dense(
128,
name="my_layer1",
activation=tf.nn.relu,
kernel_initializer=normc_initializer(1.0))(self.inputs)
layer_out = tf.keras.layers.Dense(
num_outputs,
name="my_out",
activation=None,
kernel_initializer=normc_initializer(0.01))(layer_1)
value_out = tf.keras.layers.Dense(
1,
name="value_out",
activation=None,
kernel_initializer=normc_initializer(0.01))(layer_1)
self.base_model = tf.keras.Model(self.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"])
return model_out, state
def value_function(self):
return tf.reshape(self._value_out, [-1])
class MyKerasQModel(DistributionalQModel):
"""Custom model for DQN."""
def __init__(self, obs_space, action_space, num_outputs, model_config,
name, **kw):
super(MyKerasQModel, self).__init__(
obs_space, action_space, num_outputs, model_config, name, **kw)
# Define the core model layers which will be used by the other
# output heads of DistributionalQModel
self.inputs = tf.keras.layers.Input(
shape=obs_space.shape, name="observations")
layer_1 = tf.keras.layers.Dense(
128,
name="my_layer1",
activation=tf.nn.relu,
kernel_initializer=normc_initializer(1.0))(self.inputs)
layer_out = tf.keras.layers.Dense(
num_outputs,
name="my_out",
activation=tf.nn.relu,
kernel_initializer=normc_initializer(1.0))(layer_1)
self.base_model = tf.keras.Model(self.inputs, layer_out)
self.register_variables(self.base_model.variables)
# Implement the core forward method
def forward(self, input_dict, state, seq_lens):
model_out = self.base_model(input_dict["obs"])
return model_out, state
if __name__ == "__main__":
ray.init()
args = parser.parse_args()
ModelCatalog.register_custom_model("keras_model", MyKerasModel)
ModelCatalog.register_custom_model("keras_q_model", MyKerasQModel)
tune.run(
args.run,
stop={"episode_reward_mean": args.stop},
config={
"env": "CartPole-v0",
"num_gpus": 0,
"model": {
"custom_model": "keras_q_model"
if args.run == "DQN" else "keras_model"
},
})