def _calc_adv_weights(self, adv, valid_mask):
weights = jnp.exp(adv / self._temperature)
valid_weights = weights[valid_mask]
weights_mean = jnp.mean(valid_weights)
weights_min = jnp.min(valid_weights)
weights_max = jnp.max(valid_weights)
weights = jnp.minimum(weights, self._weight_clip)
return weights, weights_mean, weights_min, weights_max
def train_epoch(self, evaluate=True):
epoch_start_time = time.time()
# Evaluate the policy.
policy_eval_start_time = time.time()
if evaluate and (self.epoch + 1) % self._eval_every_n == 0:
self.evaluate()
policy_eval_time = policy_based_utils.get_time(policy_eval_start_time)
def write_metric(key, value):
self._train_sw.scalar(key, value, step=self.epoch)
self._history.append('train', key, self.epoch, value)
# Get fresh trajectories every time.
self._should_reset_train_env = True
trajectory_collection_start_time = time.time()
logging.vlog(1, 'AWR epoch [% 6d]: collecting trajectories.',
self._epoch)
trajs, _, timing_info, self._model_state = self.collect_trajectories(
train=True, temperature=1.0, raw_trajectory=True)
del timing_info
trajectory_collection_time = policy_based_utils.get_time(
trajectory_collection_start_time)
logging.vlog(1, 'AWR epoch [% 6d]: n_trajectories [%s].', self._epoch,
len(trajs))
# Convert these into numpy now.
def extract_obs_act_rew_dones(traj_np):
return traj_np[0], traj_np[1], traj_np[2], traj_np[4]
trajs_np = [extract_obs_act_rew_dones(traj.as_numpy) for traj in trajs]
# number of new actions.
new_sample_count = sum(traj[1].shape[0] for traj in trajs_np)
self._n_observations_seen += new_sample_count
logging.vlog(1, 'AWR epoch [% 6d]: new_sample_count [%d].',
self._epoch, new_sample_count)
if self._should_write_summaries:
write_metric('trajs/batch', len(trajs))
write_metric('trajs/new_sample_count', new_sample_count)
# The number of trajectories, i.e. `B`can keep changing from iteration to
# iteration, since we are capped on the number of observations requested.
# So let's operate on each trajectory on this own?
# TODO(afrozm): So should our batches look like (B, T+1, *OBS) or B
# different examples of (T+1, *OBS) each. Since B can keep changing?
# Add these to the replay buffer.
for traj in trajs:
_ = self._replay_buffer.store(traj)
rewards = jnp.array([jnp.sum(traj[2]) for traj in trajs_np])
avg_reward = jnp.mean(rewards)
std_reward = jnp.std(rewards)
max_reward = jnp.max(rewards)
min_reward = jnp.min(rewards)
self._log('train', 'train/reward_mean_truncated', avg_reward)
if evaluate and not self._separate_eval and self._should_write_summaries:
metrics = {'raw': {1.0: {'mean': avg_reward, 'std': std_reward}}}
policy_based_utils.write_eval_reward_summaries(
metrics, self._log, self.epoch)
logging.vlog(
1, 'AWR epoch [% 6d]: Rewards avg=[%0.2f], max=[%0.2f], '
'min=[%0.2f].', self.epoch, avg_reward, max_reward, min_reward)
if self._should_write_summaries:
write_metric('reward/avg', avg_reward)
write_metric('reward/std', std_reward)
write_metric('reward/max', max_reward)
write_metric('reward/min', min_reward)
# Wrap these observations/rewards inside ReplayBuffer.
idx, valid_mask, valid_idx = self._replay_buffer.get_valid_indices()
# pylint: disable=g-complex-comprehension
observations = [
self._replay_buffer.get(
replay_buffer.ReplayBuffer.OBSERVATIONS_KEY,
idx[start_idx:end_plus_1_idx])
for (start_idx,
end_plus_1_idx) in self._replay_buffer.iterate_over_paths(idx)
]
rewards = [
self._replay_buffer.get(replay_buffer.ReplayBuffer.REWARDS_KEY,
idx[start_idx:end_plus_1_idx][:-1])
for (start_idx,
end_plus_1_idx) in self._replay_buffer.iterate_over_paths(idx)
]
# pylint: enable=g-complex-comprehension
t_final = awr_utils.padding_length(rewards, boundary=self._boundary)
logging.vlog(1, 'AWR epoch [% 6d]: t_final [%s].', self._epoch,
t_final)
if self._should_write_summaries:
write_metric('trajs/t_final', t_final)
# These padded observations are over *all* the non-final observations in
# the entire replay buffer.
# Shapes:
# padded_observations = (B, T + 1, *OBS)
# padded_observations_mask = (B, T + 1)
padded_observations, padded_observations_mask = (
awr_utils.pad_array_to_length(observations, t_final + 1))
batch = len(observations)
self._check_shapes('padded_observations',
'(batch, t_final + 1)',
padded_observations, (batch, t_final + 1),
array_prefix=2)
self._check_shapes('padded_observations_mask', '(batch, t_final + 1)',
padded_observations_mask, (batch, t_final + 1))
# Shapes:
# padded_rewards = (B, T)
# padded_rewards_mask = (B, T)
padded_rewards, padded_rewards_mask = awr_utils.pad_array_to_length(
rewards, t_final)
self._check_shapes('padded_rewards', '(batch, t_final)',
padded_rewards, (batch, t_final))
self._check_shapes('padded_rewards_mask', '(batch, t_final)',
padded_rewards_mask, (batch, t_final))
# Shapes:
# lengths = (B,)
lengths = jnp.sum(padded_rewards_mask, axis=1, dtype=jnp.int32)
self._check_shapes('lengths', '(batch,)', lengths, (batch, ))
# TODO(pkozakowski): Pass the actual actions here, to enable autoregressive
# action sampling.
dummy_actions = jnp.zeros(
(batch, t_final + 1) + self._action_shape,
self._action_dtype,
)
# Shapes:
# log_probabs_traj = (B, T + 1, #controls, #actions)
# value_predictions_traj = (B, T + 1)
log_probabs_traj, value_predictions_traj, self._model_state, unused_rng = (
self._policy_fun_all_timesteps(padded_observations, lengths,
self._model_state, self._get_rng()))
self._check_shapes(
'log_probabs_traj', '(batch, t_final + 1, n_controls, n_actions)',
log_probabs_traj,
(batch, t_final + 1, self._n_controls, self._n_actions))
self._check_shapes('value_predictions_traj', '(batch, t_final + 1)',
value_predictions_traj, (batch, t_final + 1))
# Zero out the padding's value predictions, since the net may give some
# prediction to the padding observations.
value_predictions_traj *= padded_observations_mask
# Compute td-lambda returns, and reshape to match value_predictions_traj.
list_td_lambda_returns = awr_utils.batched_compute_td_lambda_return(
padded_rewards, padded_rewards_mask, value_predictions_traj,
padded_observations_mask, self._gamma, self._td_lambda)
if logging.vlog_is_on(1) and list_td_lambda_returns:
l = len(list_td_lambda_returns)
logging.vlog(1, f'Len of list_td_lambda_returns: {l}.')
self._log_shape('td_lambda_returns[0]', list_td_lambda_returns[0])
# pad an extra 0 for each to match lengths of value predictions.
list_target_values = [
np.pad(l, (0, 1), 'constant') for l in list_td_lambda_returns
]
if batch != len(list_target_values):
raise ValueError(f'batch != len(list_target_values) : '
f'{batch} vs {len(list_target_values)}')
# Shape: (len(idx),)
target_values = np.concatenate(list_target_values)
self._check_shapes('target_values', '(len(idx),)', target_values,
(len(idx), ))
# Shape: (len(idx),)
vals = self.flatten_vals(value_predictions_traj,
padded_observations_mask)
self._check_shapes('vals', '(len(idx),)', vals, (len(idx), ))
# Calculate advantages.
adv, norm_adv, adv_mean, adv_std = self._calc_adv(
target_values, vals, valid_mask)
self._check_shapes('norm_adv', '(len(idx),)', norm_adv, (len(idx), ))
adv_weights, adv_weights_mean, adv_weights_min, adv_weights_max = (
self._calc_adv_weights(norm_adv, valid_mask))
self._check_shapes('adv_weights', '(len(idx),)', adv_weights,
(len(idx), ))
del adv, adv_mean, adv_std
del adv_weights_min, adv_weights_max, adv_weights_mean
combined_steps = int(
jnp.ceil(self._optimization_steps * new_sample_count /
self._num_samples_to_collect))
optimization_start_time = time.time()
combined_losses = self._update_combined(combined_steps, valid_idx,
target_values, adv_weights)
optimization_time = policy_based_utils.get_time(
optimization_start_time)
self._epoch += 1
if self._should_write_summaries:
write_metric('combined/optimization_steps', combined_steps)
epoch_time = policy_based_utils.get_time(epoch_start_time)
timing_dict = {
'epoch': epoch_time,
'trajectory_collection': trajectory_collection_time,
'optimization': optimization_time,
'policy_eval': policy_eval_time,
}
if self._should_write_summaries:
for k, v in timing_dict.items():
write_metric('timing/{}'.format(k), v)
# Only dump the average post losses.
if combined_losses:
for k, v in combined_losses.items():
if 'post_entropy' in k:
write_metric(k.replace('post_entropy', 'entropy'), v)
if 'post_loss' in k:
write_metric(k.replace('post_loss', 'loss'), v)
self.flush_summaries()
def train_epoch(self, evaluate=True):
def write_metric(key, value):
self._train_sw.scalar(key, value, step=self.epoch)
self._history.append('train', key, self.epoch, value)
# Get fresh trajectories every time.
self._should_reset_train_env = True
trajectory_collection_start_time = time.time()
logging.vlog(1, 'AWR epoch [% 6d]: collecting trajectories.', self._epoch)
trajs, _, timing_info, self._model_state = self.collect_trajectories(
train=True, temperature=1.0, raw_trajectory=True)
del timing_info
trajectory_collection_time = ppo.get_time(trajectory_collection_start_time)
# Convert these into numpy now.
def extract_obs_act_rew_dones(traj_np):
return traj_np[0], traj_np[1], traj_np[2], traj_np[4]
trajs_np = [extract_obs_act_rew_dones(traj.as_numpy) for traj in trajs]
# number of new actions.
new_sample_count = sum(traj[1].shape[0] for traj in trajs_np)
if self._should_write_summaries:
write_metric('trajs/batch', len(trajs))
write_metric('trajs/new_sample_count', new_sample_count)
# The number of trajectories, i.e. `B`can keep changing from iteration to
# iteration, since we are capped on the number of observations requested.
# So let's operate on each trajectory on this own?
# TODO(afrozm): So should our batches look like (B, T+1, *OBS) or B
# different examples of (T+1, *OBS) each. Since B can keep changing?
# Add these to the replay buffer.
for traj in trajs:
_ = self._replay_buffer.store(traj)
if self._should_write_summaries:
rewards = np.array([np.sum(traj[2]) for traj in trajs_np])
avg_reward = np.mean(rewards)
std_reward = np.std(rewards)
max_reward = np.max(rewards)
min_reward = np.min(rewards)
write_metric('reward/avg', avg_reward)
write_metric('reward/std', std_reward)
write_metric('reward/max', max_reward)
write_metric('reward/min', min_reward)
# Wrap these observations/rewards inside ReplayBuffer.
idx, valid_mask, valid_idx = self._replay_buffer.get_valid_indices()
# pylint: disable=g-complex-comprehension
observations = [
self._replay_buffer.get(replay_buffer.ReplayBuffer.OBSERVATIONS_KEY,
idx[start_idx:end_plus_1_idx])
for (start_idx,
end_plus_1_idx) in self._replay_buffer.iterate_over_paths(idx)
]
rewards = [
self._replay_buffer.get(replay_buffer.ReplayBuffer.REWARDS_KEY,
idx[start_idx:end_plus_1_idx][:-1])
for (start_idx,
end_plus_1_idx) in self._replay_buffer.iterate_over_paths(idx)
]
# pylint: enable=g-complex-comprehension
t_final = awr_utils.padding_length(rewards, boundary=self._boundary)
if self._should_write_summaries:
write_metric('trajs/t_final', t_final)
# These padded observations are over *all* the non-final observations in
# the entire replay buffer.
# Shapes:
# padded_observations = (B, T + 1, *OBS)
# padded_observations_mask = (B, T + 1)
padded_observations, padded_observations_mask = (
awr_utils.pad_array_to_length(observations, t_final + 1)
)
batch = len(observations)
if ((batch, t_final + 1) != padded_observations.shape[:2] or
(batch, t_final + 1) != padded_observations_mask.shape):
raise ValueError(
f'Shapes mismatch, batch {batch}, t_final {t_final}'
f'padded_observations.shape {padded_observations.shape}'
f'padded_observations_mask.shape {padded_observations_mask.shape}')
# Shapes:
# padded_rewards = (B, T)
# padded_rewards_mask = (B, T)
padded_rewards, padded_rewards_mask = awr_utils.pad_array_to_length(
rewards, t_final)
if ((padded_rewards.shape != (batch, t_final)) or
(padded_rewards_mask.shape != (batch, t_final))):
raise ValueError(
f'Shapes mismatch, batch {batch}, t_final {t_final}'
f'padded_rewards.shape {padded_rewards.shape}')
# Shapes:
# log_probabs_traj = (B, T + 1, #actions)
# value_predictions_traj = (B, T + 1)
(log_probabs_traj, value_predictions_traj) = (
self._policy_and_value_net_apply(
padded_observations,
weights=self._policy_and_value_net_weights,
state=self._model_state,
rng=self._get_rng(),
))
if ((batch, t_final + 1) != log_probabs_traj.shape[:2] or
(batch, t_final + 1) != value_predictions_traj.shape):
raise ValueError(
f'Shapes mismatch, batch {batch}, t_final {t_final}'
f'log_probabs_traj.shape {log_probabs_traj.shape}'
f'value_predictions_traj.shape {value_predictions_traj.shape}')
# Zero out the padding's value predictions, since the net may give some
# prediction to the padding observations.
value_predictions_traj *= padded_observations_mask
# Compute td-lambda returns, and reshape to match value_predictions_traj.
list_td_lambda_returns = awr_utils.batched_compute_td_lambda_return(
padded_rewards, padded_rewards_mask, value_predictions_traj,
padded_observations_mask, self._gamma, self._td_lambda)
# pad an extra 0 for each to match lengths of value predictions.
list_target_values = [
onp.pad(l, (0, 1), 'constant') for l in list_td_lambda_returns
]
if batch != len(list_target_values):
raise ValueError(f'batch != len(list_target_values) : '
f'{batch} vs {len(list_target_values)}')
# Shape: (len(idx),)
target_values = onp.concatenate(list_target_values)
if target_values.shape != (len(idx),):
raise ValueError(f'target_values.shape != (len(idx),) = '
f'{target_values.shape} != ({len(idx)},)')
# Shape: (len(idx),)
target_values = onp.concatenate(list_target_values)
vals = self.flatten_vals(value_predictions_traj, padded_observations_mask)
if vals.shape != target_values.shape:
raise ValueError(f'vals.shape != target_values.shape : '
f'{vals.shape} vs {target_values.shape}')
# Calculate advantages.
adv, norm_adv, adv_mean, adv_std = self._calc_adv(
target_values, vals, valid_mask)
adv_weights, adv_weights_mean, adv_weights_min, adv_weights_max = (
self._calc_adv_weights(norm_adv, valid_mask)
)
del adv, adv_mean, adv_std
del adv_weights_min, adv_weights_max, adv_weights_mean
combined_steps = int(
np.ceil(self._optimization_steps * new_sample_count /
self._num_samples_to_collect))
combined_losses = self._update_combined(combined_steps, valid_idx,
target_values, adv_weights)
if self._should_write_summaries:
write_metric('combined/optimization_steps', combined_steps)
timing_dict = {
'trajectory_collection': trajectory_collection_time,
# 'epoch': epoch_time,
# 'policy_eval': policy_eval_time,
# 'preprocessing': preprocessing_time,
# 'log_prob_recompute': log_prob_recompute_time,
# 'loss_compute': loss_compute_time,
# 'optimization': optimization_time,
# 'policy_save': policy_save_time,
}
if self._should_write_summaries:
for k, v in timing_dict.items():
write_metric('timing/{}'.format(k), v)
# Only dump the average post losses.
if combined_losses:
for k, v in combined_losses.items():
if 'post_entropy' in k:
write_metric(k.replace('post_entropy', 'entropy'), v)
if 'post_loss' in k:
write_metric(k.replace('post_loss', 'loss'), v)
self._epoch += 1
self.flush_summaries()