def setup_critic_optimizer(self):
logger.info('setting up critic optimizer')
normalized_critic_target_tf = tf.clip_by_value(
normalize(self.critic_target, self.ret_rms), self.return_range[0],
self.return_range[1])
self.critic_loss = tf.reduce_mean(
tf.square(self.normalized_critic_tf - normalized_critic_target_tf))
if self.critic_l2_reg > 0.:
critic_reg_vars = [
var for var in self.critic.trainable_vars
if var.name.endswith('/w:0') and 'output' not in var.name
]
for var in critic_reg_vars:
logger.info(' regularizing: {}'.format(var.name))
logger.info(' applying l2 regularization with {}'.format(
self.critic_l2_reg))
critic_reg = tc.layers.apply_regularization(
tc.layers.l2_regularizer(self.critic_l2_reg),
weights_list=critic_reg_vars)
self.critic_loss += critic_reg
critic_shapes = [
var.get_shape().as_list() for var in self.critic.trainable_vars
]
critic_nb_params = sum(
[reduce(lambda x, y: x * y, shape) for shape in critic_shapes])
logger.info(' critic shapes: {}'.format(critic_shapes))
logger.info(' critic params: {}'.format(critic_nb_params))
self.critic_grads = U.flatgrad(self.critic_loss,
self.critic.trainable_vars,
clip_norm=self.clip_norm)
self.critic_optimizer = MpiAdam(var_list=self.critic.trainable_vars,
beta1=0.9,
beta2=0.999,
epsilon=1e-08)
def display_var_info(vars):
from deephyper.search.nas.baselines import logger
count_params = 0
for v in vars:
name = v.name
if "/Adam" in name or "beta1_power" in name or "beta2_power" in name: continue
v_params = np.prod(v.shape.as_list())
count_params += v_params
if "/b:" in name or "/bias" in name: continue # Wx+b, bias is not interesting to look at => count params, but not print
logger.info(" %s%s %i params %s" % (name, " "*(55-len(name)), v_params, str(v.shape)))
logger.info("Total model parameters: %0.2f million" % (count_params*1e-6))
def get_target_updates(vars, target_vars, tau):
logger.info('setting up target updates ...')
soft_updates = []
init_updates = []
assert len(vars) == len(target_vars)
for var, target_var in zip(vars, target_vars):
logger.info(' {} <- {}'.format(target_var.name, var.name))
init_updates.append(tf.assign(target_var, var))
soft_updates.append(
tf.assign(target_var, (1. - tau) * target_var + tau * var))
assert len(init_updates) == len(vars)
assert len(soft_updates) == len(vars)
return tf.group(*init_updates), tf.group(*soft_updates)
def step_wait(self):
obs, rews, dones, infos = self.venv.step_wait()
self.step_id += 1
if self.recording:
self.video_recorder.capture_frame()
self.recorded_frames += 1
if self.recorded_frames > self.video_length:
logger.info("Saving video to ", self.video_recorder.path)
self.close_video_recorder()
elif self._video_enabled():
self.start_video_recorder()
return obs, rews, dones, infos
def get_perturbed_actor_updates(actor, perturbed_actor, param_noise_stddev):
assert len(actor.vars) == len(perturbed_actor.vars)
assert len(actor.perturbable_vars) == len(perturbed_actor.perturbable_vars)
updates = []
for var, perturbed_var in zip(actor.vars, perturbed_actor.vars):
if var in actor.perturbable_vars:
logger.info(' {} <- {} + noise'.format(perturbed_var.name,
var.name))
updates.append(
tf.assign(
perturbed_var, var + tf.random_normal(
tf.shape(var), mean=0., stddev=param_noise_stddev)))
else:
logger.info(' {} <- {}'.format(perturbed_var.name, var.name))
updates.append(tf.assign(perturbed_var, var))
assert len(updates) == len(actor.vars)
return tf.group(*updates)
def setup_param_noise(self, normalized_obs0):
assert self.param_noise is not None
# Configure perturbed actor.
param_noise_actor = copy(self.actor)
param_noise_actor.name = 'param_noise_actor'
self.perturbed_actor_tf = param_noise_actor(normalized_obs0)
logger.info('setting up param noise')
self.perturb_policy_ops = get_perturbed_actor_updates(
self.actor, param_noise_actor, self.param_noise_stddev)
# Configure separate copy for stddev adoption.
adaptive_param_noise_actor = copy(self.actor)
adaptive_param_noise_actor.name = 'adaptive_param_noise_actor'
adaptive_actor_tf = adaptive_param_noise_actor(normalized_obs0)
self.perturb_adaptive_policy_ops = get_perturbed_actor_updates(
self.actor, adaptive_param_noise_actor, self.param_noise_stddev)
self.adaptive_policy_distance = tf.sqrt(
tf.reduce_mean(tf.square(self.actor_tf - adaptive_actor_tf)))
def setup_actor_optimizer(self):
logger.info('setting up actor optimizer')
self.actor_loss = -tf.reduce_mean(self.critic_with_actor_tf)
actor_shapes = [
var.get_shape().as_list() for var in self.actor.trainable_vars
]
actor_nb_params = sum(
[reduce(lambda x, y: x * y, shape) for shape in actor_shapes])
logger.info(' actor shapes: {}'.format(actor_shapes))
logger.info(' actor params: {}'.format(actor_nb_params))
self.actor_grads = U.flatgrad(self.actor_loss,
self.actor.trainable_vars,
clip_norm=self.clip_norm)
self.actor_optimizer = MpiAdam(var_list=self.actor.trainable_vars,
beta1=0.9,
beta2=0.999,
epsilon=1e-08)
def _create_network(self, reuse=False):
logger.info("Creating a DDPG agent with action space %d x %s..." %
(self.dimu, self.max_u))
self.sess = tf_util.get_session()
# running averages
with tf.variable_scope('o_stats') as vs:
if reuse:
vs.reuse_variables()
self.o_stats = Normalizer(self.dimo,
self.norm_eps,
self.norm_clip,
sess=self.sess)
with tf.variable_scope('g_stats') as vs:
if reuse:
vs.reuse_variables()
self.g_stats = Normalizer(self.dimg,
self.norm_eps,
self.norm_clip,
sess=self.sess)
# mini-batch sampling.
batch = self.staging_tf.get()
batch_tf = OrderedDict([
(key, batch[i]) for i, key in enumerate(self.stage_shapes.keys())
])
batch_tf['r'] = tf.reshape(batch_tf['r'], [-1, 1])
#choose only the demo buffer samples
mask = np.concatenate(
(np.zeros(self.batch_size - self.demo_batch_size),
np.ones(self.demo_batch_size)),
axis=0)
# networks
with tf.variable_scope('main') as vs:
if reuse:
vs.reuse_variables()
self.main = self.create_actor_critic(batch_tf,
net_type='main',
**self.__dict__)
vs.reuse_variables()
with tf.variable_scope('target') as vs:
if reuse:
vs.reuse_variables()
target_batch_tf = batch_tf.copy()
target_batch_tf['o'] = batch_tf['o_2']
target_batch_tf['g'] = batch_tf['g_2']
self.target = self.create_actor_critic(target_batch_tf,
net_type='target',
**self.__dict__)
vs.reuse_variables()
assert len(self._vars("main")) == len(self._vars("target"))
# loss functions
target_Q_pi_tf = self.target.Q_pi_tf
clip_range = (-self.clip_return,
0. if self.clip_pos_returns else np.inf)
target_tf = tf.clip_by_value(
batch_tf['r'] + self.gamma * target_Q_pi_tf, *clip_range)
self.Q_loss_tf = tf.reduce_mean(
tf.square(tf.stop_gradient(target_tf) - self.main.Q_tf))
if self.bc_loss == 1 and self.q_filter == 1: # train with demonstrations and use bc_loss and q_filter both
maskMain = tf.reshape(
tf.boolean_mask(self.main.Q_tf > self.main.Q_pi_tf,
mask), [-1]
) #where is the demonstrator action better than actor action according to the critic? choose those samples only
#define the cloning loss on the actor's actions only on the samples which adhere to the above masks
self.cloning_loss_tf = tf.reduce_sum(
tf.square(
tf.boolean_mask(tf.boolean_mask((self.main.pi_tf), mask),
maskMain,
axis=0) -
tf.boolean_mask(tf.boolean_mask((batch_tf['u']), mask),
maskMain,
axis=0)))
self.pi_loss_tf = -self.prm_loss_weight * tf.reduce_mean(
self.main.Q_pi_tf
) #primary loss scaled by it's respective weight prm_loss_weight
self.pi_loss_tf += self.prm_loss_weight * self.action_l2 * tf.reduce_mean(
tf.square(self.main.pi_tf / self.max_u)
) #L2 loss on action values scaled by the same weight prm_loss_weight
self.pi_loss_tf += self.aux_loss_weight * self.cloning_loss_tf #adding the cloning loss to the actor loss as an auxilliary loss scaled by its weight aux_loss_weight
elif self.bc_loss == 1 and self.q_filter == 0: # train with demonstrations without q_filter
self.cloning_loss_tf = tf.reduce_sum(
tf.square(
tf.boolean_mask((self.main.pi_tf), mask) -
tf.boolean_mask((batch_tf['u']), mask)))
self.pi_loss_tf = -self.prm_loss_weight * tf.reduce_mean(
self.main.Q_pi_tf)
self.pi_loss_tf += self.prm_loss_weight * self.action_l2 * tf.reduce_mean(
tf.square(self.main.pi_tf / self.max_u))
self.pi_loss_tf += self.aux_loss_weight * self.cloning_loss_tf
else: #If not training with demonstrations
self.pi_loss_tf = -tf.reduce_mean(self.main.Q_pi_tf)
self.pi_loss_tf += self.action_l2 * tf.reduce_mean(
tf.square(self.main.pi_tf / self.max_u))
Q_grads_tf = tf.gradients(self.Q_loss_tf, self._vars('main/Q'))
pi_grads_tf = tf.gradients(self.pi_loss_tf, self._vars('main/pi'))
assert len(self._vars('main/Q')) == len(Q_grads_tf)
assert len(self._vars('main/pi')) == len(pi_grads_tf)
self.Q_grads_vars_tf = zip(Q_grads_tf, self._vars('main/Q'))
self.pi_grads_vars_tf = zip(pi_grads_tf, self._vars('main/pi'))
self.Q_grad_tf = flatten_grads(grads=Q_grads_tf,
var_list=self._vars('main/Q'))
self.pi_grad_tf = flatten_grads(grads=pi_grads_tf,
var_list=self._vars('main/pi'))
# optimizers
self.Q_adam = MpiAdam(self._vars('main/Q'), scale_grad_by_procs=False)
self.pi_adam = MpiAdam(self._vars('main/pi'),
scale_grad_by_procs=False)
# polyak averaging
self.main_vars = self._vars('main/Q') + self._vars('main/pi')
self.target_vars = self._vars('target/Q') + self._vars('target/pi')
self.stats_vars = self._global_vars('o_stats') + self._global_vars(
'g_stats')
self.init_target_net_op = list(
map(lambda v: v[0].assign(v[1]),
zip(self.target_vars, self.main_vars)))
self.update_target_net_op = list(
map(
lambda v: v[0].assign(self.polyak * v[0] +
(1. - self.polyak) * v[1]),
zip(self.target_vars, self.main_vars)))
# initialize all variables
tf.variables_initializer(self._global_vars('')).run()
self._sync_optimizers()
self._init_target_net()
def init_demo_buffer(
self,
demoDataFile,
update_stats=True): #function that initializes the demo buffer
demoData = np.load(
demoDataFile) #load the demonstration data from data file
info_keys = [
key.replace('info_', '') for key in self.input_dims.keys()
if key.startswith('info_')
]
info_values = [
np.empty((self.T - 1, 1, self.input_dims['info_' + key]),
np.float32) for key in info_keys
]
demo_data_obs = demoData['obs']
demo_data_acs = demoData['acs']
demo_data_info = demoData['info']
for epsd in range(
self.num_demo
): # we initialize the whole demo buffer at the start of the training
obs, acts, goals, achieved_goals = [], [], [], []
i = 0
for transition in range(self.T - 1):
obs.append(
[demo_data_obs[epsd][transition].get('observation')])
acts.append([demo_data_acs[epsd][transition]])
goals.append(
[demo_data_obs[epsd][transition].get('desired_goal')])
achieved_goals.append(
[demo_data_obs[epsd][transition].get('achieved_goal')])
for idx, key in enumerate(info_keys):
info_values[idx][transition,
i] = demo_data_info[epsd][transition][key]
obs.append([demo_data_obs[epsd][self.T - 1].get('observation')])
achieved_goals.append(
[demo_data_obs[epsd][self.T - 1].get('achieved_goal')])
episode = dict(o=obs, u=acts, g=goals, ag=achieved_goals)
for key, value in zip(info_keys, info_values):
episode['info_{}'.format(key)] = value
episode = convert_episode_to_batch_major(episode)
global DEMO_BUFFER
DEMO_BUFFER.store_episode(
episode
) # create the observation dict and append them into the demonstration buffer
logger.debug("Demo buffer size currently ",
DEMO_BUFFER.get_current_size()
) #print out the demonstration buffer size
if update_stats:
# add transitions to normalizer to normalize the demo data as well
episode['o_2'] = episode['o'][:, 1:, :]
episode['ag_2'] = episode['ag'][:, 1:, :]
num_normalizing_transitions = transitions_in_episode_batch(
episode)
transitions = self.sample_transitions(
episode, num_normalizing_transitions)
o, g, ag = transitions['o'], transitions['g'], transitions[
'ag']
transitions['o'], transitions['g'] = self._preprocess_og(
o, ag, g)
# No need to preprocess the o_2 and g_2 since this is only used for stats
self.o_stats.update(transitions['o'])
self.g_stats.update(transitions['g'])
self.o_stats.recompute_stats()
self.g_stats.recompute_stats()
episode.clear()
logger.info("Demo buffer size: ", DEMO_BUFFER.get_current_size()
) #print out the demonstration buffer size
def learn(network, env,
seed=None,
total_timesteps=None,
nb_epochs=None, # with default settings, perform 1M steps total
nb_epoch_cycles=20,
nb_rollout_steps=100,
reward_scale=1.0,
render=False,
render_eval=False,
noise_type='adaptive-param_0.2',
normalize_returns=False,
normalize_observations=True,
critic_l2_reg=1e-2,
actor_lr=1e-4,
critic_lr=1e-3,
popart=False,
gamma=0.99,
clip_norm=None,
nb_train_steps=50, # per epoch cycle and MPI worker,
nb_eval_steps=100,
batch_size=64, # per MPI worker
tau=0.01,
eval_env=None,
param_noise_adaption_interval=50,
**network_kwargs):
set_global_seeds(seed)
if total_timesteps is not None:
assert nb_epochs is None
nb_epochs = int(total_timesteps) // (nb_epoch_cycles * nb_rollout_steps)
else:
nb_epochs = 500
if MPI is not None:
rank = MPI.COMM_WORLD.Get_rank()
else:
rank = 0
nb_actions = env.action_space.shape[-1]
assert (np.abs(env.action_space.low) == env.action_space.high).all() # we assume symmetric actions.
memory = Memory(limit=int(1e6), action_shape=env.action_space.shape, observation_shape=env.observation_space.shape)
critic = Critic(network=network, **network_kwargs)
actor = Actor(nb_actions, network=network, **network_kwargs)
action_noise = None
param_noise = None
if noise_type is not None:
for current_noise_type in noise_type.split(','):
current_noise_type = current_noise_type.strip()
if current_noise_type == 'none':
pass
elif 'adaptive-param' in current_noise_type:
_, stddev = current_noise_type.split('_')
param_noise = AdaptiveParamNoiseSpec(initial_stddev=float(stddev), desired_action_stddev=float(stddev))
elif 'normal' in current_noise_type:
_, stddev = current_noise_type.split('_')
action_noise = NormalActionNoise(mu=np.zeros(nb_actions), sigma=float(stddev) * np.ones(nb_actions))
elif 'ou' in current_noise_type:
_, stddev = current_noise_type.split('_')
action_noise = OrnsteinUhlenbeckActionNoise(mu=np.zeros(nb_actions), sigma=float(stddev) * np.ones(nb_actions))
else:
raise RuntimeError('unknown noise type "{}"'.format(current_noise_type))
max_action = env.action_space.high
logger.info('scaling actions by {} before executing in env'.format(max_action))
agent = DDPG(actor, critic, memory, env.observation_space.shape, env.action_space.shape,
gamma=gamma, tau=tau, normalize_returns=normalize_returns, normalize_observations=normalize_observations,
batch_size=batch_size, action_noise=action_noise, param_noise=param_noise, critic_l2_reg=critic_l2_reg,
actor_lr=actor_lr, critic_lr=critic_lr, enable_popart=popart, clip_norm=clip_norm,
reward_scale=reward_scale)
logger.info('Using agent with the following configuration:')
logger.info(str(agent.__dict__.items()))
eval_episode_rewards_history = deque(maxlen=100)
episode_rewards_history = deque(maxlen=100)
sess = U.get_session()
# Prepare everything.
agent.initialize(sess)
sess.graph.finalize()
agent.reset()
obs = env.reset()
if eval_env is not None:
eval_obs = eval_env.reset()
nenvs = obs.shape[0]
episode_reward = np.zeros(nenvs, dtype = np.float32) #vector
episode_step = np.zeros(nenvs, dtype = int) # vector
episodes = 0 #scalar
t = 0 # scalar
epoch = 0
start_time = time.time()
epoch_episode_rewards = []
epoch_episode_steps = []
epoch_actions = []
epoch_qs = []
epoch_episodes = 0
for epoch in range(nb_epochs):
for cycle in range(nb_epoch_cycles):
# Perform rollouts.
if nenvs > 1:
# if simulating multiple envs in parallel, impossible to reset agent at the end of the episode in each
# of the environments, so resetting here instead
agent.reset()
for t_rollout in range(nb_rollout_steps):
# Predict next action.
action, q, _, _ = agent.step(obs, apply_noise=True, compute_Q=True)
# Execute next action.
if rank == 0 and render:
env.render()
# max_action is of dimension A, whereas action is dimension (nenvs, A) - the multiplication gets broadcasted to the batch
new_obs, r, done, info = env.step(max_action * action) # scale for execution in env (as far as DDPG is concerned, every action is in [-1, 1])
# note these outputs are batched from vecenv
t += 1
if rank == 0 and render:
env.render()
episode_reward += r
episode_step += 1
# Book-keeping.
epoch_actions.append(action)
epoch_qs.append(q)
agent.store_transition(obs, action, r, new_obs, done) #the batched data will be unrolled in memory.py's append.
obs = new_obs
for d in range(len(done)):
if done[d]:
# Episode done.
epoch_episode_rewards.append(episode_reward[d])
episode_rewards_history.append(episode_reward[d])
epoch_episode_steps.append(episode_step[d])
episode_reward[d] = 0.
episode_step[d] = 0
epoch_episodes += 1
episodes += 1
if nenvs == 1:
agent.reset()
# Train.
epoch_actor_losses = []
epoch_critic_losses = []
epoch_adaptive_distances = []
for t_train in range(nb_train_steps):
# Adapt param noise, if necessary.
if memory.nb_entries >= batch_size and t_train % param_noise_adaption_interval == 0:
distance = agent.adapt_param_noise()
epoch_adaptive_distances.append(distance)
cl, al = agent.train()
epoch_critic_losses.append(cl)
epoch_actor_losses.append(al)
agent.update_target_net()
# Evaluate.
eval_episode_rewards = []
eval_qs = []
if eval_env is not None:
nenvs_eval = eval_obs.shape[0]
eval_episode_reward = np.zeros(nenvs_eval, dtype = np.float32)
for t_rollout in range(nb_eval_steps):
eval_action, eval_q, _, _ = agent.step(eval_obs, apply_noise=False, compute_Q=True)
eval_obs, eval_r, eval_done, eval_info = eval_env.step(max_action * eval_action) # scale for execution in env (as far as DDPG is concerned, every action is in [-1, 1])
if render_eval:
eval_env.render()
eval_episode_reward += eval_r
eval_qs.append(eval_q)
for d in range(len(eval_done)):
if eval_done[d]:
eval_episode_rewards.append(eval_episode_reward[d])
eval_episode_rewards_history.append(eval_episode_reward[d])
eval_episode_reward[d] = 0.0
if MPI is not None:
mpi_size = MPI.COMM_WORLD.Get_size()
else:
mpi_size = 1
# Log stats.
# XXX shouldn't call np.mean on variable length lists
duration = time.time() - start_time
stats = agent.get_stats()
combined_stats = stats.copy()
combined_stats['rollout/return'] = np.mean(epoch_episode_rewards)
combined_stats['rollout/return_history'] = np.mean(episode_rewards_history)
combined_stats['rollout/episode_steps'] = np.mean(epoch_episode_steps)
combined_stats['rollout/actions_mean'] = np.mean(epoch_actions)
combined_stats['rollout/Q_mean'] = np.mean(epoch_qs)
combined_stats['train/loss_actor'] = np.mean(epoch_actor_losses)
combined_stats['train/loss_critic'] = np.mean(epoch_critic_losses)
combined_stats['train/param_noise_distance'] = np.mean(epoch_adaptive_distances)
combined_stats['total/duration'] = duration
combined_stats['total/steps_per_second'] = float(t) / float(duration)
combined_stats['total/episodes'] = episodes
combined_stats['rollout/episodes'] = epoch_episodes
combined_stats['rollout/actions_std'] = np.std(epoch_actions)
# Evaluation statistics.
if eval_env is not None:
combined_stats['eval/return'] = eval_episode_rewards
combined_stats['eval/return_history'] = np.mean(eval_episode_rewards_history)
combined_stats['eval/Q'] = eval_qs
combined_stats['eval/episodes'] = len(eval_episode_rewards)
def as_scalar(x):
if isinstance(x, np.ndarray):
assert x.size == 1
return x[0]
elif np.isscalar(x):
return x
else:
raise ValueError('expected scalar, got %s'%x)
combined_stats_sums = np.array([ np.array(x).flatten()[0] for x in combined_stats.values()])
if MPI is not None:
combined_stats_sums = MPI.COMM_WORLD.allreduce(combined_stats_sums)
combined_stats = {k : v / mpi_size for (k,v) in zip(combined_stats.keys(), combined_stats_sums)}
# Total statistics.
combined_stats['total/epochs'] = epoch + 1
combined_stats['total/steps'] = t
for key in sorted(combined_stats.keys()):
logger.record_tabular(key, combined_stats[key])
if rank == 0:
logger.dump_tabular()
logger.info('')
logdir = logger.get_dir()
if rank == 0 and logdir:
if hasattr(env, 'get_state'):
with open(os.path.join(logdir, 'env_state.pkl'), 'wb') as f:
pickle.dump(env.get_state(), f)
if eval_env and hasattr(eval_env, 'get_state'):
with open(os.path.join(logdir, 'eval_env_state.pkl'), 'wb') as f:
pickle.dump(eval_env.get_state(), f)
return agent
def log_params(params, logger=logger):
for key in sorted(params.keys()):
logger.info('{}: {}'.format(key, params[key]))
def train(*, policy, rollout_worker, evaluator,
n_epochs, n_test_rollouts, n_cycles, n_batches, policy_save_interval,
save_path, demo_file, **kwargs):
rank = MPI.COMM_WORLD.Get_rank()
if save_path:
latest_policy_path = os.path.join(save_path, 'policy_latest.pkl')
best_policy_path = os.path.join(save_path, 'policy_best.pkl')
periodic_policy_path = os.path.join(save_path, 'policy_{}.pkl')
logger.info("Training...")
best_success_rate = -1
if policy.bc_loss == 1: policy.init_demo_buffer(demo_file) #initialize demo buffer if training with demonstrations
# num_timesteps = n_epochs * n_cycles * rollout_length * number of rollout workers
for epoch in range(n_epochs):
# train
rollout_worker.clear_history()
for _ in range(n_cycles):
episode = rollout_worker.generate_rollouts()
policy.store_episode(episode)
for _ in range(n_batches):
policy.train()
policy.update_target_net()
# test
evaluator.clear_history()
for _ in range(n_test_rollouts):
evaluator.generate_rollouts()
# record logs
logger.record_tabular('epoch', epoch)
for key, val in evaluator.logs('test'):
logger.record_tabular(key, mpi_average(val))
for key, val in rollout_worker.logs('train'):
logger.record_tabular(key, mpi_average(val))
for key, val in policy.logs():
logger.record_tabular(key, mpi_average(val))
if rank == 0:
logger.dump_tabular()
# save the policy if it's better than the previous ones
success_rate = mpi_average(evaluator.current_success_rate())
if rank == 0 and success_rate >= best_success_rate and save_path:
best_success_rate = success_rate
logger.info('New best success rate: {}. Saving policy to {} ...'.format(best_success_rate, best_policy_path))
evaluator.save_policy(best_policy_path)
evaluator.save_policy(latest_policy_path)
if rank == 0 and policy_save_interval > 0 and epoch % policy_save_interval == 0 and save_path:
policy_path = periodic_policy_path.format(epoch)
logger.info('Saving periodic policy to {} ...'.format(policy_path))
evaluator.save_policy(policy_path)
# make sure that different threads have different seeds
local_uniform = np.random.uniform(size=(1,))
root_uniform = local_uniform.copy()
MPI.COMM_WORLD.Bcast(root_uniform, root=0)
if rank != 0:
assert local_uniform[0] != root_uniform[0]
return policy
