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# Copyright 2018 The TensorFlow Authors All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
"""A DDPG/NAF agent.
Implements the Deep Deterministic Policy Gradient (DDPG) algorithm from
"Continuous control with deep reinforcement learning" - Lilicrap et al.
https://arxiv.org/abs/1509.02971, and the Normalized Advantage Functions (NAF)
algorithm "Continuous Deep Q-Learning with Model-based Acceleration" - Gu et al.
https://arxiv.org/pdf/1603.00748.
"""
import tensorflow as tf
slim = tf.contrib.slim
import gin.tf
from utils import utils
from agents import ddpg_networks as networks
@gin.configurable
class DdpgAgent(object):
"""An RL agent that learns using the DDPG algorithm.
Example usage:
def critic_net(states, actions):
...
def actor_net(states, num_action_dims):
...
Given a tensorflow environment tf_env,
(of type learning.deepmind.rl.environments.tensorflow.python.tfpyenvironment)
obs_spec = tf_env.observation_spec()
action_spec = tf_env.action_spec()
ddpg_agent = agent.DdpgAgent(obs_spec,
action_spec,
actor_net=actor_net,
critic_net=critic_net)
we can perform actions on the environment as follows:
state = tf_env.observations()[0]
action = ddpg_agent.actor_net(tf.expand_dims(state, 0))[0, :]
transition_type, reward, discount = tf_env.step([action])
Train:
critic_loss = ddpg_agent.critic_loss(states, actions, rewards, discounts,
next_states)
actor_loss = ddpg_agent.actor_loss(states)
critic_train_op = slim.learning.create_train_op(
critic_loss,
critic_optimizer,
variables_to_train=ddpg_agent.get_trainable_critic_vars(),
)
actor_train_op = slim.learning.create_train_op(
actor_loss,
actor_optimizer,
variables_to_train=ddpg_agent.get_trainable_actor_vars(),
)
"""
ACTOR_NET_SCOPE = 'actor_net'
CRITIC_NET_SCOPE = 'critic_net'
TARGET_ACTOR_NET_SCOPE = 'target_actor_net'
TARGET_CRITIC_NET_SCOPE = 'target_critic_net'
def __init__(self,
observation_spec,
action_spec,
actor_net=networks.actor_net,
critic_net=networks.critic_net,
td_errors_loss=tf.losses.huber_loss,
dqda_clipping=0.,
actions_regularizer=0.,
target_q_clipping=None,
residual_phi=0.0,
debug_summaries=False):
"""Constructs a DDPG agent.
Args:
observation_spec: A TensorSpec defining the observations.
action_spec: A BoundedTensorSpec defining the actions.
actor_net: A callable that creates the actor network. Must take the
following arguments: states, num_actions. Please see networks.actor_net
for an example.
critic_net: A callable that creates the critic network. Must take the
following arguments: states, actions. Please see networks.critic_net
for an example.
td_errors_loss: A callable defining the loss function for the critic
td error.
dqda_clipping: (float) clips the gradient dqda element-wise between
[-dqda_clipping, dqda_clipping]. Does not perform clipping if
dqda_clipping == 0.
actions_regularizer: A scalar, when positive penalizes the norm of the
actions. This can prevent saturation of actions for the actor_loss.
target_q_clipping: (tuple of floats) clips target q values within
(low, high) values when computing the critic loss.
residual_phi: (float) [0.0, 1.0] Residual algorithm parameter that
interpolates between Q-learning and residual gradient algorithm.
http://www.leemon.com/papers/1995b.pdf
debug_summaries: If True, add summaries to help debug behavior.
Raises:
ValueError: If 'dqda_clipping' is < 0.
"""
self._observation_spec = observation_spec[0]
self._action_spec = action_spec[0]
self._state_shape = tf.TensorShape([None]).concatenate(
self._observation_spec.shape)
self._action_shape = tf.TensorShape([None]).concatenate(
self._action_spec.shape)
self._num_action_dims = self._action_spec.shape.num_elements()
self._scope = tf.get_variable_scope().name
self._actor_net = tf.make_template(
self.ACTOR_NET_SCOPE, actor_net, create_scope_now_=True)
self._critic_net = tf.make_template(
self.CRITIC_NET_SCOPE, critic_net, create_scope_now_=True)
self._target_actor_net = tf.make_template(
self.TARGET_ACTOR_NET_SCOPE, actor_net, create_scope_now_=True)
self._target_critic_net = tf.make_template(
self.TARGET_CRITIC_NET_SCOPE, critic_net, create_scope_now_=True)
self._td_errors_loss = td_errors_loss
if dqda_clipping < 0:
raise ValueError('dqda_clipping must be >= 0.')
self._dqda_clipping = dqda_clipping
self._actions_regularizer = actions_regularizer
self._target_q_clipping = target_q_clipping
self._residual_phi = residual_phi
self._debug_summaries = debug_summaries
def _batch_state(self, state):
"""Convert state to a batched state.
Args:
state: Either a list/tuple with an state tensor [num_state_dims].
Returns:
A tensor [1, num_state_dims]
"""
if isinstance(state, (tuple, list)):
state = state[0]
if state.get_shape().ndims == 1:
state = tf.expand_dims(state, 0)
return state
def action(self, state):
"""Returns the next action for the state.
Args:
state: A [num_state_dims] tensor representing a state.
Returns:
A [num_action_dims] tensor representing the action.
"""
return self.actor_net(self._batch_state(state), stop_gradients=True)[0, :]
@gin.configurable('ddpg_sample_action')
def sample_action(self, state, stddev=1.0):
"""Returns the action for the state with additive noise.
Args:
state: A [num_state_dims] tensor representing a state.
stddev: stddev for the Ornstein-Uhlenbeck noise.
Returns:
A [num_action_dims] action tensor.
"""
agent_action = self.action(state)
agent_action += tf.random_normal(tf.shape(agent_action)) * stddev
return utils.clip_to_spec(agent_action, self._action_spec)
def actor_net(self, states, stop_gradients=False):
"""Returns the output of the actor network.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
stop_gradients: (boolean) if true, gradients cannot be propogated through
this operation.
Returns:
A [batch_size, num_action_dims] tensor of actions.
Raises:
ValueError: If `states` does not have the expected dimensions.
"""
self._validate_states(states)
actions = self._actor_net(states, self._action_spec)
if stop_gradients:
actions = tf.stop_gradient(actions)
return actions
def critic_net(self, states, actions, for_critic_loss=False):
"""Returns the output of the critic network.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
actions: A [batch_size, num_action_dims] tensor representing a batch
of actions.
Returns:
q values: A [batch_size] tensor of q values.
Raises:
ValueError: If `states` or `actions' do not have the expected dimensions.
"""
self._validate_states(states)
self._validate_actions(actions)
return self._critic_net(states, actions,
for_critic_loss=for_critic_loss)
def target_actor_net(self, states):
"""Returns the output of the target actor network.
The target network is used to compute stable targets for training.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
Returns:
A [batch_size, num_action_dims] tensor of actions.
Raises:
ValueError: If `states` does not have the expected dimensions.
"""
self._validate_states(states)
actions = self._target_actor_net(states, self._action_spec)
return tf.stop_gradient(actions)
def target_critic_net(self, states, actions, for_critic_loss=False):
"""Returns the output of the target critic network.
The target network is used to compute stable targets for training.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
actions: A [batch_size, num_action_dims] tensor representing a batch
of actions.
Returns:
q values: A [batch_size] tensor of q values.
Raises:
ValueError: If `states` or `actions' do not have the expected dimensions.
"""
self._validate_states(states)
self._validate_actions(actions)
return tf.stop_gradient(
self._target_critic_net(states, actions,
for_critic_loss=for_critic_loss))
def value_net(self, states, for_critic_loss=False):
"""Returns the output of the critic evaluated with the actor.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
Returns:
q values: A [batch_size] tensor of q values.
"""
actions = self.actor_net(states)
return self.critic_net(states, actions,
for_critic_loss=for_critic_loss)
def target_value_net(self, states, for_critic_loss=False):
"""Returns the output of the target critic evaluated with the target actor.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
Returns:
q values: A [batch_size] tensor of q values.
"""
target_actions = self.target_actor_net(states)
return self.target_critic_net(states, target_actions,
for_critic_loss=for_critic_loss)
def critic_loss(self, states, actions, rewards, discounts,
next_states):
"""Computes a loss for training the critic network.
The loss is the mean squared error between the Q value predictions of the
critic and Q values estimated using TD-lambda.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
actions: A [batch_size, num_action_dims] tensor representing a batch
of actions.
rewards: A [batch_size, ...] tensor representing a batch of rewards,
broadcastable to the critic net output.
discounts: A [batch_size, ...] tensor representing a batch of discounts,
broadcastable to the critic net output.
next_states: A [batch_size, num_state_dims] tensor representing a batch
of next states.
Returns:
A rank-0 tensor representing the critic loss.
Raises:
ValueError: If any of the inputs do not have the expected dimensions, or
if their batch_sizes do not match.
"""
self._validate_states(states)
self._validate_actions(actions)
self._validate_states(next_states)
target_q_values = self.target_value_net(next_states, for_critic_loss=True)
td_targets = target_q_values * discounts + rewards
if self._target_q_clipping is not None:
td_targets = tf.clip_by_value(td_targets, self._target_q_clipping[0],
self._target_q_clipping[1])
q_values = self.critic_net(states, actions, for_critic_loss=True)
td_errors = td_targets - q_values
if self._debug_summaries:
gen_debug_td_error_summaries(
target_q_values, q_values, td_targets, td_errors)
loss = self._td_errors_loss(td_targets, q_values)
if self._residual_phi > 0.0: # compute residual gradient loss
residual_q_values = self.value_net(next_states, for_critic_loss=True)
residual_td_targets = residual_q_values * discounts + rewards
if self._target_q_clipping is not None:
residual_td_targets = tf.clip_by_value(residual_td_targets,
self._target_q_clipping[0],
self._target_q_clipping[1])
residual_td_errors = residual_td_targets - q_values
residual_loss = self._td_errors_loss(
residual_td_targets, residual_q_values)
loss = (loss * (1.0 - self._residual_phi) +
residual_loss * self._residual_phi)
return loss
def actor_loss(self, states):
"""Computes a loss for training the actor network.
Note that output does not represent an actual loss. It is called a loss only
in the sense that its gradient w.r.t. the actor network weights is the
correct gradient for training the actor network,
i.e. dloss/dweights = (dq/da)*(da/dweights)
which is the gradient used in Algorithm 1 of Lilicrap et al.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
Returns:
A rank-0 tensor representing the actor loss.
Raises:
ValueError: If `states` does not have the expected dimensions.
"""
self._validate_states(states)
actions = self.actor_net(states, stop_gradients=False)
critic_values = self.critic_net(states, actions)
q_values = self.critic_function(critic_values, states)
dqda = tf.gradients([q_values], [actions])[0]
dqda_unclipped = dqda
if self._dqda_clipping > 0:
dqda = tf.clip_by_value(dqda, -self._dqda_clipping, self._dqda_clipping)
actions_norm = tf.norm(actions)
if self._debug_summaries:
with tf.name_scope('dqda'):
tf.summary.scalar('actions_norm', actions_norm)
tf.summary.histogram('dqda', dqda)
tf.summary.histogram('dqda_unclipped', dqda_unclipped)
tf.summary.histogram('actions', actions)
for a in range(self._num_action_dims):
tf.summary.histogram('dqda_unclipped_%d' % a, dqda_unclipped[:, a])
tf.summary.histogram('dqda_%d' % a, dqda[:, a])
actions_norm *= self._actions_regularizer
return slim.losses.mean_squared_error(tf.stop_gradient(dqda + actions),
actions,
scope='actor_loss') + actions_norm
@gin.configurable('ddpg_critic_function')
def critic_function(self, critic_values, states, weights=None):
"""Computes q values based on critic_net outputs, states, and weights.
Args:
critic_values: A tf.float32 [batch_size, ...] tensor representing outputs
from the critic net.
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
weights: A list or Numpy array or tensor with a shape broadcastable to
`critic_values`.
Returns:
A tf.float32 [batch_size] tensor representing q values.
"""
del states # unused args
if weights is not None:
weights = tf.convert_to_tensor(weights, dtype=critic_values.dtype)
critic_values *= weights
if critic_values.shape.ndims > 1:
critic_values = tf.reduce_sum(critic_values,
range(1, critic_values.shape.ndims))
critic_values.shape.assert_has_rank(1)
return critic_values
@gin.configurable('ddpg_update_targets')
def update_targets(self, tau=1.0):
"""Performs a soft update of the target network parameters.
For each weight w_s in the actor/critic networks, and its corresponding
weight w_t in the target actor/critic networks, a soft update is:
w_t = (1- tau) x w_t + tau x ws
Args:
tau: A float scalar in [0, 1]
Returns:
An operation that performs a soft update of the target network parameters.
Raises:
ValueError: If `tau` is not in [0, 1].
"""
if tau < 0 or tau > 1:
raise ValueError('Input `tau` should be in [0, 1].')
update_actor = utils.soft_variables_update(
slim.get_trainable_variables(
utils.join_scope(self._scope, self.ACTOR_NET_SCOPE)),
slim.get_trainable_variables(
utils.join_scope(self._scope, self.TARGET_ACTOR_NET_SCOPE)),
tau)
update_critic = utils.soft_variables_update(
slim.get_trainable_variables(
utils.join_scope(self._scope, self.CRITIC_NET_SCOPE)),
slim.get_trainable_variables(
utils.join_scope(self._scope, self.TARGET_CRITIC_NET_SCOPE)),
tau)
return tf.group(update_actor, update_critic, name='update_targets')
def get_trainable_critic_vars(self):
"""Returns a list of trainable variables in the critic network.
Returns:
A list of trainable variables in the critic network.
"""
return slim.get_trainable_variables(
utils.join_scope(self._scope, self.CRITIC_NET_SCOPE))
def get_trainable_actor_vars(self):
"""Returns a list of trainable variables in the actor network.
Returns:
A list of trainable variables in the actor network.
"""
return slim.get_trainable_variables(
utils.join_scope(self._scope, self.ACTOR_NET_SCOPE))
def get_critic_vars(self):
"""Returns a list of all variables in the critic network.
Returns:
A list of trainable variables in the critic network.
"""
return slim.get_model_variables(
utils.join_scope(self._scope, self.CRITIC_NET_SCOPE))
def get_actor_vars(self):
"""Returns a list of all variables in the actor network.
Returns:
A list of trainable variables in the actor network.
"""
return slim.get_model_variables(
utils.join_scope(self._scope, self.ACTOR_NET_SCOPE))
def _validate_states(self, states):
"""Raises a value error if `states` does not have the expected shape.
Args:
states: A tensor.
Raises:
ValueError: If states.shape or states.dtype are not compatible with
observation_spec.
"""
states.shape.assert_is_compatible_with(self._state_shape)
if not states.dtype.is_compatible_with(self._observation_spec.dtype):
raise ValueError('states.dtype={} is not compatible with'
' observation_spec.dtype={}'.format(
states.dtype, self._observation_spec.dtype))
def _validate_actions(self, actions):
"""Raises a value error if `actions` does not have the expected shape.
Args:
actions: A tensor.
Raises:
ValueError: If actions.shape or actions.dtype are not compatible with
action_spec.
"""
actions.shape.assert_is_compatible_with(self._action_shape)
if not actions.dtype.is_compatible_with(self._action_spec.dtype):
raise ValueError('actions.dtype={} is not compatible with'
' action_spec.dtype={}'.format(
actions.dtype, self._action_spec.dtype))
@gin.configurable
class TD3Agent(DdpgAgent):
"""An RL agent that learns using the TD3 algorithm."""
ACTOR_NET_SCOPE = 'actor_net'
CRITIC_NET_SCOPE = 'critic_net'
CRITIC_NET2_SCOPE = 'critic_net2'
TARGET_ACTOR_NET_SCOPE = 'target_actor_net'
TARGET_CRITIC_NET_SCOPE = 'target_critic_net'
TARGET_CRITIC_NET2_SCOPE = 'target_critic_net2'
def __init__(self,
observation_spec,
action_spec,
actor_net=networks.actor_net,
critic_net=networks.critic_net,
td_errors_loss=tf.losses.huber_loss,
dqda_clipping=0.,
actions_regularizer=0.,
target_q_clipping=None,
residual_phi=0.0,
debug_summaries=False):
"""Constructs a TD3 agent.
Args:
observation_spec: A TensorSpec defining the observations.
action_spec: A BoundedTensorSpec defining the actions.
actor_net: A callable that creates the actor network. Must take the
following arguments: states, num_actions. Please see networks.actor_net
for an example.
critic_net: A callable that creates the critic network. Must take the
following arguments: states, actions. Please see networks.critic_net
for an example.
td_errors_loss: A callable defining the loss function for the critic
td error.
dqda_clipping: (float) clips the gradient dqda element-wise between
[-dqda_clipping, dqda_clipping]. Does not perform clipping if
dqda_clipping == 0.
actions_regularizer: A scalar, when positive penalizes the norm of the
actions. This can prevent saturation of actions for the actor_loss.
target_q_clipping: (tuple of floats) clips target q values within
(low, high) values when computing the critic loss.
residual_phi: (float) [0.0, 1.0] Residual algorithm parameter that
interpolates between Q-learning and residual gradient algorithm.
http://www.leemon.com/papers/1995b.pdf
debug_summaries: If True, add summaries to help debug behavior.
Raises:
ValueError: If 'dqda_clipping' is < 0.
"""
self._observation_spec = observation_spec[0]
self._action_spec = action_spec[0]
self._state_shape = tf.TensorShape([None]).concatenate(
self._observation_spec.shape)
self._action_shape = tf.TensorShape([None]).concatenate(
self._action_spec.shape)
self._num_action_dims = self._action_spec.shape.num_elements()
self._scope = tf.get_variable_scope().name
self._actor_net = tf.make_template(
self.ACTOR_NET_SCOPE, actor_net, create_scope_now_=True)
self._critic_net = tf.make_template(
self.CRITIC_NET_SCOPE, critic_net, create_scope_now_=True)
self._critic_net2 = tf.make_template(
self.CRITIC_NET2_SCOPE, critic_net, create_scope_now_=True)
self._target_actor_net = tf.make_template(
self.TARGET_ACTOR_NET_SCOPE, actor_net, create_scope_now_=True)
self._target_critic_net = tf.make_template(
self.TARGET_CRITIC_NET_SCOPE, critic_net, create_scope_now_=True)
self._target_critic_net2 = tf.make_template(
self.TARGET_CRITIC_NET2_SCOPE, critic_net, create_scope_now_=True)
self._td_errors_loss = td_errors_loss
if dqda_clipping < 0:
raise ValueError('dqda_clipping must be >= 0.')
self._dqda_clipping = dqda_clipping
self._actions_regularizer = actions_regularizer
self._target_q_clipping = target_q_clipping
self._residual_phi = residual_phi
self._debug_summaries = debug_summaries
def get_trainable_critic_vars(self):
"""Returns a list of trainable variables in the critic network.
NOTE: This gets the vars of both critic networks.
Returns:
A list of trainable variables in the critic network.
"""
return (
slim.get_trainable_variables(
utils.join_scope(self._scope, self.CRITIC_NET_SCOPE)))
def critic_net(self, states, actions, for_critic_loss=False):
"""Returns the output of the critic network.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
actions: A [batch_size, num_action_dims] tensor representing a batch
of actions.
Returns:
q values: A [batch_size] tensor of q values.
Raises:
ValueError: If `states` or `actions' do not have the expected dimensions.
"""
values1 = self._critic_net(states, actions,
for_critic_loss=for_critic_loss)
values2 = self._critic_net2(states, actions,
for_critic_loss=for_critic_loss)
if for_critic_loss:
return values1, values2
return values1
def target_critic_net(self, states, actions, for_critic_loss=False):
"""Returns the output of the target critic network.
The target network is used to compute stable targets for training.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
actions: A [batch_size, num_action_dims] tensor representing a batch
of actions.
Returns:
q values: A [batch_size] tensor of q values.
Raises:
ValueError: If `states` or `actions' do not have the expected dimensions.
"""
self._validate_states(states)
self._validate_actions(actions)
values1 = tf.stop_gradient(
self._target_critic_net(states, actions,
for_critic_loss=for_critic_loss))
values2 = tf.stop_gradient(
self._target_critic_net2(states, actions,
for_critic_loss=for_critic_loss))
if for_critic_loss:
return values1, values2
return values1
def value_net(self, states, for_critic_loss=False):
"""Returns the output of the critic evaluated with the actor.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
Returns:
q values: A [batch_size] tensor of q values.
"""
actions = self.actor_net(states)
return self.critic_net(states, actions,
for_critic_loss=for_critic_loss)
def target_value_net(self, states, for_critic_loss=False):
"""Returns the output of the target critic evaluated with the target actor.
Args:
states: A [batch_size, num_state_dims] tensor representing a batch
of states.
Returns:
q values: A [batch_size] tensor of q values.
"""
target_actions = self.target_actor_net(states)
noise = tf.clip_by_value(
tf.random_normal(tf.shape(target_actions), stddev=0.2), -0.5, 0.5)
values1, values2 = self.target_critic_net(
states, target_actions + noise,
for_critic_loss=for_critic_loss)
values = tf.minimum(values1, values2)
return values, values
@gin.configurable('td3_update_targets')
def update_targets(self, tau=1.0):
"""Performs a soft update of the target network parameters.
For each weight w_s in the actor/critic networks, and its corresponding
weight w_t in the target actor/critic networks, a soft update is:
w_t = (1- tau) x w_t + tau x ws
Args:
tau: A float scalar in [0, 1]
Returns:
An operation that performs a soft update of the target network parameters.
Raises:
ValueError: If `tau` is not in [0, 1].
"""
if tau < 0 or tau > 1:
raise ValueError('Input `tau` should be in [0, 1].')
update_actor = utils.soft_variables_update(
slim.get_trainable_variables(
utils.join_scope(self._scope, self.ACTOR_NET_SCOPE)),
slim.get_trainable_variables(
utils.join_scope(self._scope, self.TARGET_ACTOR_NET_SCOPE)),
tau)
# NOTE: This updates both critic networks.
update_critic = utils.soft_variables_update(
slim.get_trainable_variables(
utils.join_scope(self._scope, self.CRITIC_NET_SCOPE)),
slim.get_trainable_variables(
utils.join_scope(self._scope, self.TARGET_CRITIC_NET_SCOPE)),
tau)
return tf.group(update_actor, update_critic, name='update_targets')
def gen_debug_td_error_summaries(
target_q_values, q_values, td_targets, td_errors):
"""Generates debug summaries for critic given a set of batch samples.
Args:
target_q_values: set of predicted next stage values.
q_values: current predicted value for the critic network.
td_targets: discounted target_q_values with added next stage reward.
td_errors: the different between td_targets and q_values.
"""
with tf.name_scope('td_errors'):
tf.summary.histogram('td_targets', td_targets)
tf.summary.histogram('q_values', q_values)
tf.summary.histogram('target_q_values', target_q_values)
tf.summary.histogram('td_errors', td_errors)
with tf.name_scope('td_targets'):
tf.summary.scalar('mean', tf.reduce_mean(td_targets))
tf.summary.scalar('max', tf.reduce_max(td_targets))
tf.summary.scalar('min', tf.reduce_min(td_targets))
with tf.name_scope('q_values'):
tf.summary.scalar('mean', tf.reduce_mean(q_values))
tf.summary.scalar('max', tf.reduce_max(q_values))
tf.summary.scalar('min', tf.reduce_min(q_values))
with tf.name_scope('target_q_values'):
tf.summary.scalar('mean', tf.reduce_mean(target_q_values))
tf.summary.scalar('max', tf.reduce_max(target_q_values))
tf.summary.scalar('min', tf.reduce_min(target_q_values))
with tf.name_scope('td_errors'):
tf.summary.scalar('mean', tf.reduce_mean(td_errors))
tf.summary.scalar('max', tf.reduce_max(td_errors))
tf.summary.scalar('min', tf.reduce_min(td_errors))
tf.summary.scalar('mean_abs', tf.reduce_mean(tf.abs(td_errors)))
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