def __init__(self, env, time_steps, hidden_dim):
self.name = 'DDPG' # name for uploading results
self.scale = env.asset
self.unit = env.unit
self.seed = env.rd_seed
self.time_dim = time_steps
self.state_dim = env.observation_space.shape[1]
self.action_dim = env.action_space.shape[0]
self.batch_size = 64
self.memory_size = self.time_dim + self.batch_size * 10
self.start_size = self.time_dim + self.batch_size * 2
# Initialise actor & critic networks
self.actor_network = Actor(self.time_dim, self.state_dim,
self.action_dim, hidden_dim)
self.critic_network = Critic(self.time_dim, self.state_dim,
self.action_dim, hidden_dim)
# Initialize replay buffer
self.replay_state = torch.zeros(
(self.start_size - 1, 3, self.state_dim), device=cuda)
self.replay_next_state = torch.zeros(
(self.start_size - 1, 3, self.state_dim), device=cuda)
self.replay_action = torch.zeros(
(self.start_size - 1, 1, self.state_dim), device=cuda)
self.replay_reward = torch.zeros((self.start_size - 1, ), device=cuda)
# Initialize a random process the Ornstein-Uhlenbeck process for action exploration
self.exploration_noise = OUNoise(self.action_dim,
sigma=0.01 / self.action_dim)
self.initial()
def __init__(
self,
obs_dim,
action_dim,
action_gain,
actor_learning_rate=0.0001,
critic_learning_rate=0.001,
gamma=0.99,
tau=0.001,
):
self.obs_dim = obs_dim
self.action_dim = action_dim
self.gamma = gamma
self.tau = tau
# make main networks
self.actor = Actor(obs_dim, action_dim, action_gain,
actor_learning_rate)
self.critic = Critic(obs_dim, action_dim, critic_learning_rate)
# make target networks
self.target_actor = Actor(obs_dim, action_dim, action_gain)
self.target_actor.model.set_weights(self.actor.model.get_weights())
self.target_critic = Critic(obs_dim, action_dim)
self.target_critic.model.set_weights(self.critic.model.get_weights())
def __init__(self, state_size, action_size, num_agents, random_seed):
"""Initialize an Agent object.
Params
======
state_size (int): dimension of each state
action_size (int): dimension of each action
num_agents (int): number of agents
random_seed (int): random seed
"""
self.state_size = state_size
self.action_size = action_size
self.num_agents = num_agents
self.seed = random.seed(random_seed)
self.eps = eps_start
self.t_step = 0
# Actor Network (w/ Target Network)
self.actor_local = Actor(state_size, action_size, random_seed).to(device)
self.actor_target = Actor(state_size, action_size, random_seed).to(device)
self.actor_optimizer = optim.Adam(self.actor_local.parameters(), lr=LR_ACTOR)
# Critic Network (w/ Target Network)
self.critic_local = Critic(state_size, action_size, random_seed).to(device)
self.critic_target = Critic(state_size, action_size, random_seed).to(device)
self.critic_optimizer = optim.Adam(self.critic_local.parameters(), lr=LR_CRITIC, weight_decay=WEIGHT_DECAY)
# Noise process
self.noise = OUNoise((num_agents, action_size), random_seed)
# Replay memory
self.memory = ReplayBuffer(action_size, BUFFER_SIZE, BATCH_SIZE, random_seed)
def __init__(self, state_size, action_size, random_seed):
self.state_size = state_size
self.action_size = action_size
self.seed = random.seed(random_seed)
self.epsilon = EPS
#--- actor -----#
self.actor_local = Actor(state_size, action_size,
random_seed).to(device)
self.actor_target = Actor(state_size, action_size,
random_seed).to(device)
self.actor_optimizer = optim.Adam(self.actor_local.parameters(),
lr=1e-3)
#---- critic -----#
self.critic_local = Critic(state_size, action_size,
random_seed).to(device)
self.critic_target = Critic(state_size, action_size,
random_seed).to(device)
self.critic_optimizer = optim.Adam(self.critic_local.parameters(),
lr=1e-3,
weight_decay=0)
self.noise = OUNoise(action_size, random_seed)
self.memory = ReplayBuffer(action_size, BUFFER_SIZE, BATCH_SIZE,
random_seed)
def __init__(self, state_size, action_size, random_seed, num_agents):
"""Initialize an Agent object.
"""
self.state_size = state_size
self.action_size = action_size
self.seed = random.seed(random_seed)
# Actor Network (w/ Target Network)
self.actor_local = Actor(state_size, action_size,
random_seed).to(device)
self.actor_target = Actor(state_size, action_size,
random_seed).to(device)
self.actor_optimizer = optim.Adam(self.actor_local.parameters(),
lr=LR_ACTOR)
# Critic Network (w/ Target Network)
self.critic_local = Critic(state_size, action_size,
random_seed).to(device)
self.critic_target = Critic(state_size, action_size,
random_seed).to(device)
self.critic_optimizer = optim.Adam(self.critic_local.parameters(),
lr=LR_CRITIC,
weight_decay=WEIGHT_DECAY)
# Noise process
self.noise = OUNoise(action_size, random_seed, sigma=0.1)
# Replay buffer
self.memory = ReplayBuffer(action_size, BUFFER_SIZE, BATCH_SIZE,
random_seed)
self.num_agents = num_agents
def __init__(
self,
state_size=24,
action_size=2,
BATCH_SIZE=128,
BUFFER_SIZE=int(1e6),
discount_factor=1,
tau=1e-2,
noise_coefficient_start=5,
noise_coefficient_decay=0.99,
LR_ACTOR=1e-3,
LR_CRITIC=1e-3,
WEIGHT_DECAY=1e-3,
device=torch.device("cuda:0" if torch.cuda.is_available() else "cpu")):
"""
state_size (int): dimension of each state
action_size (int): dimension of each action
BATCH_SIZE (int): mini batch size
BUFFER_SIZE (int): experience storing lenght, keep it as high as possible
discount_factor (float): discount factor for calculating Q_target
tau (float): interpolation parameter for updating target network
noise_coefficient_start (float): value to be multiplied to OUNoise sample
noise_coefficient_decay (float): exponential decay factor for value to be multiplied to OUNoise sample
LR_ACTOR (float): learning rate for actor network
LR_CRITIC (float): learning rate for critic network
WEIGHT_DECAY (float): Weight decay for critic network optimizer
device : "cuda:0" if torch.cuda.is_available() else "cpu"
"""
self.state_size = state_size
print(device)
self.action_size = action_size
self.BATCH_SIZE = BATCH_SIZE
self.BUFFER_SIZE = BUFFER_SIZE
self.discount_factor = discount_factor
self.tau = tau
self.noise_coefficient = noise_coefficient_start
self.noise_coefficient_decay = noise_coefficient_decay
self.steps_completed = 0
self.device = device
# Actor Network (w/ Target Network)
self.actor_local = Actor(state_size, action_size).to(self.device)
self.actor_target = Actor(state_size, action_size).to(self.device)
self.actor_optimizer = optim.Adam(self.actor_local.parameters(),
lr=LR_ACTOR)
# Critic Network (w/ Target Network)
self.critic_local = Critic(state_size, action_size).to(self.device)
self.critic_target = Critic(state_size, action_size).to(self.device)
self.critic_optimizer = optim.Adam(self.critic_local.parameters(),
lr=LR_CRITIC,
weight_decay=WEIGHT_DECAY)
# Noise process
self.noise = OUNoise((1, action_size))
# Replay memory
self.memory = ReplayBuffer(action_size, self.BUFFER_SIZE,
self.BATCH_SIZE)
def __init__(self,
env: gym.Env,
memory_size: int,
batch_size: int,
ou_noise_theta: float,
ou_noise_sigma: float,
gamma: float = 0.99,
tau: float = 5e-3,
initial_random_episode: int = 1e4,
name_cases='myproject'):
""" Initialize. """
# Logger
self.wandb = wandb.init(project=name_cases)
obs_dim = env.observation_space.shape[0]
action_dim = env.action_space.shape[0]
self.env = env
self.memory = ReplayBuffer(memory_size)
self.batch_size = batch_size
self.gamma = gamma
self.tau = tau
self.initial_random_episode = initial_random_episode
# noise
self.noise = OUNoise(
action_dim,
theta=ou_noise_theta,
sigma=ou_noise_sigma,
)
# device: cpu / gpu
self.device = torch.device(
"cuda" if torch.cuda.is_available() else "cpu")
print(self.device)
# networks
self.actor = Actor(obs_dim, action_dim).to(self.device)
self.actor_target = Actor(obs_dim, action_dim).to(self.device)
self.actor_target.load_state_dict(self.actor.state_dict())
self.critic = Critic(obs_dim + action_dim).to(self.device)
self.critic_target = Critic(obs_dim + action_dim).to(self.device)
self.critic_target.load_state_dict(self.critic.state_dict())
# optimizer
self.actor_optimizer = optim.Adam(self.actor.parameters(), lr=3e-4)
self.critic_optimizer = optim.Adam(self.critic.parameters(), lr=1e-3)
# transition to store in memory
self.transition = list()
# total steps count
self.total_step = 0
# mode: train / test
self.is_test = False
self.populate(self.initial_random_episode)
def create_critic(self, alpha, hidden_layers):
params = {
'input_shape': self.env.observation_space.shape,
'output_shape': self.env.action_space.shape,
'hidden_layers': hidden_layers
}
self.critic = OpenStruct()
self.critic.online = Critic("{}.critic.online".format(self.name), **params)
self.critic.target = Critic("{}.critic.target".format(self.name), **params)
def test_critic(self):
Actor_obj = Actor(1, 16, 4)
Critic_obj = Critic(4, 16, 1)
# critic_optimizer = optim.SGD(Critic_obj.parameters(), lr=C_learning_rate)
y = Actor_obj.forward(torch.FloatTensor([1]))
# Forward Propagation
y_pred = Critic_obj.forward(y)
self.assertTrue(len(y_pred) == 1)
def __init__(self, n, state_size, action_size, random_seed, params):
"""Initialize an Agent object.
Params
======
n (int): number of agents in env
state_size (int): dimension of each state
action_size (int): dimension of each action
random_seed (int): random seed
params (dict): dictionary with hyperparameters name-value pairs
"""
self.n = n
self.state_size = state_size
self.action_size = action_size
self.seed = random.seed(random_seed)
self.BUFFER_SIZE = params["BUFFER_SIZE"]
self.BATCH_SIZE = params["BATCH_SIZE"]
self.GAMMA = params["GAMMA"]
self.TAU = params["TAU"]
self.LR_ACTOR = params["LR_ACTOR"]
self.LR_CRITIC = params["LR_CRITIC"]
self.WEIGHT_DECAY = params["WEIGHT_DECAY"]
self.N_UPDATES = params["N_UPDATES"]
self.UPDATE_STEP = params["UPDATE_STEP"]
# Actor Network (w/ Target Network)
self.actor_local = Actor(state_size, action_size,
random_seed).to(device)
self.actor_target = Actor(state_size, action_size,
random_seed).to(device)
self.actor_optimizer = optim.Adam(self.actor_local.parameters(),
lr=self.LR_ACTOR)
# Critic Network (w/ Target Network)
self.critic_local = Critic(state_size, action_size,
random_seed).to(device)
self.critic_target = Critic(state_size, action_size,
random_seed).to(device)
self.critic_optimizer = optim.Adam(self.critic_local.parameters(),
lr=self.LR_CRITIC,
weight_decay=self.WEIGHT_DECAY)
# Noise process
self.noise = OUNoise(self.n, action_size, random_seed)
# Replay memory
self.memory = ReplayBuffer(action_size, self.BUFFER_SIZE,
self.BATCH_SIZE, random_seed)
#Count timesteps
self.timestep = 0
def __init__(self,
init_pose=None,
init_velocities=None,
init_angle_velocities=None,
runtime=5.,
target_pos=None,
buffer_size=150000,
batch_size=32,
gamma=0.99,
replay_alpha=0.5,
beta_limit=10000):
self.task = Task(init_pose, init_velocities, init_angle_velocities,
runtime, target_pos)
self.state_size = self.task.state_size
self.action_size = self.task.action_size
self.state = self.task.reset()
self.memory = PrioritizedReplay(buffer_size, batch_size, replay_alpha,
beta_limit)
self.actor = Actor(self.state_size, self.action_size,
self.task.action_low, self.task.action_high)
self.actor_weights = self.actor.model.trainable_weights
self.actor_target = Actor(self.state_size, self.action_size,
self.task.action_low, self.task.action_high)
self.critic = Critic(self.state_size, self.action_size)
self.critic_weights = self.critic.model.trainable_weights
self.critic_target = Critic(self.state_size, self.action_size)
self.gamma = gamma
# how much influence older weights have when updating target
self.tau = 0.03
#noise
# GENTLE LANDING
#self.mu = 0
#self.theta = 0.1
#self.sigma = 25
self.mu = 0
self.theta = 0.1
self.sigma = 9
self.noise = Noise(self.action_size, self.mu, self.theta, self.sigma)
self.episodes = 0
self.training_step = 0
def __init__(self,
env,
act_dim,
state_dim,
goal_dim,
act_range,
buffer_size=int(1e6),
gamma=0.98,
lr=0.001,
tau=0.95):
""" Initialization
"""
# Environment and A2C parameters
self.act_dim = act_dim
self.act_range = act_range
self.env_dim = state_dim + goal_dim
self.gamma = gamma
self.lr = lr
self.tau = tau
self.env = env
# Create actor and critic networks
self.actor_network = Actor(self.env_dim, act_dim, act_range)
self.actor_target_network = Actor(self.env_dim, act_dim, act_range)
self.actor_target_network.load_state_dict(
self.actor_network.state_dict())
self.critic_network = Critic(self.env_dim, act_dim, act_range)
self.critic_target_network = Critic(self.env_dim, act_dim, act_range)
self.actor_target_network.load_state_dict(
self.actor_network.state_dict())
sync_networks(self.actor_network)
sync_networks(self.critic_network)
# Optimizer
self.actor_optim = torch.optim.Adam(self.actor_network.parameters(),
lr=lr)
self.critic_optim = torch.optim.Adam(self.critic_network.parameters(),
lr=lr)
# Replay buffer
# self.buffer = MemoryBuffer(buffer_size)
self.buffer = ReplayMemory(buffer_size)
# Normalizers
self.goal_normalizer = Normalizer(
goal_dim, default_clip_range=5) # Clip between [-5, 5]
self.state_normalizer = Normalizer(state_dim, default_clip_range=5)
def test_actor(self):
Actor_obj = Actor(1, 16, 4)
Critic_obj = Critic(4, 16, 1)
# actor_optimizer = optim.SGD(Actor_obj.parameters(), lr=0.1, momentum=0.5)
# Forward Propagation
y = Actor_obj.forward(torch.FloatTensor([1]))
self.assertTrue(len(y) == 4)
class ActorCritic(object):
def __init__(self, env):
LR_A = 0.001 # learning rate for actor
LR_C = 0.01 # learning rate for critic
num_features = env.observation_space.shape[0]
# num_features = 14
num_actions = env.action_space.shape[0]
self.action_space = env.action_space
sess = tf.Session()
self.actor = Actor(
sess,
n_features=num_features,
action_bound=[env.action_space.low[0], env.action_space.high[0]],
lr=LR_A)
self.critic = Critic(
sess, n_features=num_features, lr=LR_C
) # we need a good teacher, so the teacher should learn faster than the actor
sess.run(tf.global_variables_initializer())
def get_action(self, state, episode_percentage):
# state = state[0:14]
# Sometimes pick random action to explore
if np.random.random() < self.get_exploration_prob(episode_percentage):
# print 'random'
return self.action_space.sample()
else:
# print 'not random'
return self.actor.choose_action(state)[0]
def get_exploration_prob(self, episode_percentage):
# if (episode_percentage > .8):
# epsilon = 0.3
# else:
epsilon = -1 * (episode_percentage**2) + 1
# epsilon = -1 * (episode_percentage - 1) ** 3
# epsilon = -0.8 * (episode_percentage - 1) ** 3 + 0.2
# epsilon = -0.8 * episode_percentage + 1
# print epsilon
return epsilon
def update(self, state, action, reward, new_state):
# state = state[0:14]
# new_state = new_state[0:14]
td_error = self.critic.learn(
state, reward,
new_state) # gradient = grad[r + gamma * V(s_) - V(s)]
# print td_error
self.actor.learn(
state, action,
td_error) # true_gradient = grad[logPi(s,a) * td_error]
def get_name(self):
return 'ActorCritic'
def __init__(self, env):
LR_A = 0.001 # learning rate for actor
LR_C = 0.01 # learning rate for critic
num_features = env.observation_space.shape[0]
# num_features = 14
num_actions = env.action_space.shape[0]
self.action_space = env.action_space
sess = tf.Session()
self.actor = Actor(
sess,
n_features=num_features,
action_bound=[env.action_space.low[0], env.action_space.high[0]],
lr=LR_A)
self.critic = Critic(
sess, n_features=num_features, lr=LR_C
) # we need a good teacher, so the teacher should learn faster than the actor
sess.run(tf.global_variables_initializer())
def __init__(self,
env=gym.make('Pendulum-v0'),
s_dim=2,
a_dim=1,
gamma=0.99,
episodes=100,
tau=0.001,
buffer_size=1e06,
minibatch_size=64,
actor_lr=0.001,
critic_lr=0.001,
save_name='final_weights',
render=False):
self.save_name = save_name
self.render = render
self.env = env
self.upper_bound = env.action_space.high[0]
self.lower_bound = env.action_space.low[0]
self.EPISODES = episodes
self.MAX_TIME_STEPS = 200
self.s_dim = s_dim
self.a_dim = a_dim
self.GAMMA = gamma
self.TAU = tau
self.buffer_size = buffer_size
self.minibatch_size = minibatch_size
self.actor_lr = actor_lr
self.critic_lr = critic_lr
self.ou_noise = OUNoise(mean=np.zeros(1))
self.actor = Actor(self.s_dim, self.a_dim).model()
self.target_actor = Actor(self.s_dim, self.a_dim).model()
self.actor_opt = tf.keras.optimizers.Adam(learning_rate=self.actor_lr)
self.target_actor.set_weights(self.actor.get_weights())
self.critic = Critic(self.s_dim, self.a_dim).model()
self.critic_opt = tf.keras.optimizers.Adam(
learning_rate=self.critic_lr)
self.target_critic = Critic(self.s_dim, self.a_dim).model()
self.target_critic.set_weights(self.critic.get_weights())
self.replay_buffer = ReplayBuffer(self.buffer_size)
def __init__(self,
n_state,
n_action,
a_limit,
model_folder=None,
memory_size=10000,
batch_size=32,
tau=0.01,
gamma=0.99,
var=3.0):
# Record the parameters
self.n_state = n_state
self.n_action = n_action
self.a_limit = a_limit
self.memory_size = memory_size
self.model_folder = model_folder
self.batch_size = batch_size
self.tau = tau
self.gamma = gamma
self.var = var
# Create the network and related objects
self.memory = np.zeros(
[self.memory_size, 2 * self.n_state + self.n_action + 1],
dtype=np.float32)
self.memory_counter = 0
self.eval_actor = Actor(self.n_state, self.n_action, self.a_limit)
self.eval_critic = Critic(self.n_state, self.n_action)
self.target_actor = Actor(self.n_state,
self.n_action,
self.a_limit,
trainable=False)
self.target_critic = Critic(self.n_state,
self.n_action,
trainable=False)
self.actor_optimizer = Adam(self.eval_actor.parameters(), lr=0.001)
self.critic_optimizer = Adam(self.eval_critic.parameters(), lr=0.002)
self.criterion = nn.MSELoss()
# Make sure the parameter of target network is the same as evaluate network
self.hardCopy()
def __init__(self,
state_size,
action_size,
action_sigma=0.1,
memory_size=1000000,
batch=128,
sigma=0.2,
noise_clip=0.5,
gamma=0.99,
update_frequency=2,
seed=0):
'''
TD3 Agent
:param state_size: State Dimension
:param action_size: Action dimension
:param action_sigma: standard deviation of the noise to be added to the action
:param memory_size:
:param batch:
:param sigma: Standard deviation of the noise to be added to the target function (Chapter 5.3 of TD3 Paper)
:param noise_clip: How much noise to allow
:param gamma:
:param update_frequency:
:param seed:
'''
self.state_size = state_size
self.action_size = action_size
self.action_sigma = action_sigma
self.sigma = sigma
self.noise_clip = noise_clip
self.gamma = gamma
self.update_frequency = update_frequency
self.seed = seed
self.actor = Actor(self.state_size, self.action_size).to(device)
self.critic0 = Critic(self.state_size, self.action_size).to(device)
#second Critic as described in the paper
# https: // arxiv.org / pdf / 1802.09477.pdf
self.critic1 = Critic(self.state_size, self.action_size).to(device)
self.target_actor = Actor(self.state_size, self.action_size).to(device)
self.target_critic0 = Critic(self.state_size,
self.action_size).to(device)
# second Critic as described in the paper
# https: // arxiv.org / pdf / 1802.09477.pdf
self.target_critic1 = Critic(self.state_size,
self.action_size).to(device)
self.memory = ReplayBuffer(memory_size, batch, seed=seed)
self.actor_optimizer = Adam(self.actor.parameters(), lr=ACTOR_LR)
self.critic0_optimizer = Adam(self.critic0.parameters(), lr=VALUE0_LR)
self.critic1_optimizer = Adam(self.critic1.parameters(), lr=VALUE1_LR)
self.soft_update(self.actor, self.target_actor, 1)
self.soft_update(self.critic0, self.target_critic0, 1)
self.soft_update(self.critic1, self.target_critic1, 1)
def MountainCar():
env = gym.make('MountainCar-v0')
env = env.unwrapped
env.reset()
env.render()
n_features = env.observation_space.shape[0]
n_actions = env.action_space.n
sess = tf.Session()
actor = Actor(sess, n_features, n_actions, lr=LR_A)
critic = Critic(sess, n_features, lr=LR_C)
sess.run(tf.global_variables_initializer())
game = Game(env, actor, critic)
game.run_mountain_car()
def main(args):
with tf.device(args['device']):
# tf
tf.set_random_seed(args['rand_seed'])
sess = tf.Session(config=tf.ConfigProto(allow_soft_placement=True))
# env
env = gym.make('TestEnv-v0')
env.seed(args['rand_seed'])
s_dim = env.observation_space.shape[0]
a_dim = env.action_space.shape[0]
concat_dim = 2
batched_s_dim = [None, s_dim, concat_dim]
batched_a_dim = [None, a_dim]
# agents
actor = Actor(sess, args['actor_lr'], args['tau'], args['batch_size'],
args['clip_val'], batched_s_dim, batched_a_dim)
critic = Critic(sess, args['critic_lr'], args['tau'], args['clip_val'],
batched_s_dim, batched_a_dim)
# experience
exp = Experience(args['buffer_size'], args['batch_size'],
args['rand_seed'])
# noise
actor_noise = ActorNoise(actor.predict,
a_dim,
noise_type=args['noise_type'])
# initialize
init = tf.global_variables_initializer()
sess.run(init)
saver = Model(sess, args['restore_path'])
saver.restore_model()
# training
her = HER(saver, exp, env, actor, critic, actor_noise)
if args['mode'] == 'train':
her.train(args['gamma'], args['her_k'], args['max_episodes'],
args['max_episode_len'], args['replay_len'])
else:
her.play(args['max_episodes'], args['max_episode_len'])
def CartPoleAC():
env1 = gym.make('CartPole-v0')
# env2 = gym.make('CartPole-v0')
env1.seed(10)
# env2.seed(2)
env1 = env1.unwrapped
env1.reset()
# env2 = env2.unwrapped
# env2.reset()
n_features = env1.observation_space.shape[0]
n_actions = env1.action_space.n
sess = tf.Session()
actor = Actor(sess, n_features, n_actions, lr=LR_A)
critic = Critic(sess, n_features, lr=LR_C)
sess.run(tf.global_variables_initializer())
g = Game(env1, actor, critic)
g.run()
def __init__(self,
env,
memory_size=1000000,
batch=128,
sigma=0.2,
noise_clip=0.5,
gamma=0.99,
update_frequency=2):
self.states = env.observation_space
self.state_size = env.observation_space.shape[0]
self.actions = env.action_space
self.action_size = env.action_space.shape[0]
self.sigma = sigma
self.noise_clip = noise_clip
self.gamma = gamma
self.update_frequency = update_frequency
self.actor = Actor(self.state_size, self.action_size).to(device)
self.critic0 = Critic(self.state_size, self.action_size).to(device)
self.critic1 = Critic(self.state_size, self.action_size).to(device)
self.target_actor = Actor(self.state_size, self.action_size).to(device)
self.target_critic0 = Critic(self.state_size,
self.action_size).to(device)
self.target_critic1 = Critic(self.state_size,
self.action_size).to(device)
self.memory = ReplayBuffer(memory_size, batch)
self.actor_optimizer = Adam(self.actor.parameters(), lr=ACTOR_LR)
self.critic0_optimizer = Adam(self.critic0.parameters(), lr=VALUE0_LR)
self.critic1_optimizer = Adam(self.critic1.parameters(), lr=VALUE1_LR)
self.soft_update(self.actor, self.target_actor, 1)
self.soft_update(self.critic0, self.target_critic0, 1)
self.soft_update(self.critic1, self.target_critic1, 1)
class Agent():
def __init__(self,
env,
memory_size=1000000,
batch=128,
sigma=0.2,
noise_clip=0.5,
gamma=0.99,
update_frequency=2):
self.states = env.observation_space
self.state_size = env.observation_space.shape[0]
self.actions = env.action_space
self.action_size = env.action_space.shape[0]
self.sigma = sigma
self.noise_clip = noise_clip
self.gamma = gamma
self.update_frequency = update_frequency
self.actor = Actor(self.state_size, self.action_size).to(device)
self.critic0 = Critic(self.state_size, self.action_size).to(device)
self.critic1 = Critic(self.state_size, self.action_size).to(device)
self.target_actor = Actor(self.state_size, self.action_size).to(device)
self.target_critic0 = Critic(self.state_size,
self.action_size).to(device)
self.target_critic1 = Critic(self.state_size,
self.action_size).to(device)
self.memory = ReplayBuffer(memory_size, batch)
self.actor_optimizer = Adam(self.actor.parameters(), lr=ACTOR_LR)
self.critic0_optimizer = Adam(self.critic0.parameters(), lr=VALUE0_LR)
self.critic1_optimizer = Adam(self.critic1.parameters(), lr=VALUE1_LR)
self.soft_update(self.actor, self.target_actor, 1)
self.soft_update(self.critic0, self.target_critic0, 1)
self.soft_update(self.critic1, self.target_critic1, 1)
def act(self, state, step, epsilon=True):
state = torch.from_numpy(np.asarray(state)).float().to(device)
action = self.actor.forward(state)
action = action.detach().cpu().numpy()
if epsilon:
noise = np.random.normal(0, 0.1, action.shape[0])
action += noise
return action
def update(self, step):
state, action, reward, next_state, done = self.memory.sample()
next_state_action = self.target_actor(next_state)
noise = Normal(torch.zeros(self.action_size), self.sigma).sample()
noise = torch.clamp(noise, -self.noise_clip,
self.noise_clip).to(device)
next_state_action += noise
target_Q0 = self.target_critic0(next_state, next_state_action)
target_Q1 = self.target_critic1(next_state, next_state_action)
target_Q = torch.min(target_Q0, target_Q1)
target_value = reward + self.gamma * target_Q * (1.0 - done)
expected_Q0 = self.critic0(state, action)
expected_Q1 = self.critic1(state, action)
critic_0_loss = F.mse_loss(expected_Q0, target_value.detach())
critic_1_loss = F.mse_loss(expected_Q1, target_value.detach())
self.critic0_optimizer.zero_grad()
critic_0_loss.backward()
self.critic0_optimizer.step()
self.critic1_optimizer.zero_grad()
critic_1_loss.backward()
self.critic1_optimizer.step()
if step % self.update_frequency == 0:
actor_loss = self.critic0.forward(state, self.actor.forward(state))
actor_loss = -actor_loss.mean()
self.actor_optimizer.zero_grad()
actor_loss.backward()
self.actor_optimizer.step()
self.soft_update(self.critic0, self.target_critic0, TRANSFER_RATE)
self.soft_update(self.critic1, self.target_critic1, TRANSFER_RATE)
self.soft_update(self.actor, self.target_actor, TRANSFER_RATE)
def soft_update(self, local_model, target_model, tao):
for target_param, local_param in zip(target_model.parameters(),
local_model.parameters()):
target_param.data.copy_(tao * local_param.data +
(1.0 - tao) * target_param.data)
def add_to_memory(self, state, action, reward, next_state, done):
self.memory.add(state, action, reward, next_state, done)
class DDPG:
def __init__(self,
env=gym.make('Pendulum-v0'),
s_dim=2,
a_dim=1,
gamma=0.99,
episodes=100,
tau=0.001,
buffer_size=1e06,
minibatch_size=64,
actor_lr=0.001,
critic_lr=0.001,
save_name='final_weights',
render=False):
self.save_name = save_name
self.render = render
self.env = env
self.upper_bound = env.action_space.high[0]
self.lower_bound = env.action_space.low[0]
self.EPISODES = episodes
self.MAX_TIME_STEPS = 200
self.s_dim = s_dim
self.a_dim = a_dim
self.GAMMA = gamma
self.TAU = tau
self.buffer_size = buffer_size
self.minibatch_size = minibatch_size
self.actor_lr = actor_lr
self.critic_lr = critic_lr
self.ou_noise = OUNoise(mean=np.zeros(1))
self.actor = Actor(self.s_dim, self.a_dim).model()
self.target_actor = Actor(self.s_dim, self.a_dim).model()
self.actor_opt = tf.keras.optimizers.Adam(learning_rate=self.actor_lr)
self.target_actor.set_weights(self.actor.get_weights())
self.critic = Critic(self.s_dim, self.a_dim).model()
self.critic_opt = tf.keras.optimizers.Adam(
learning_rate=self.critic_lr)
self.target_critic = Critic(self.s_dim, self.a_dim).model()
self.target_critic.set_weights(self.critic.get_weights())
self.replay_buffer = ReplayBuffer(self.buffer_size)
def update_target(self):
# Two methods to update the target actor
# Method 1:
self.target_actor.set_weights(
np.array(self.actor.get_weights()) * self.TAU +
np.array(self.target_actor.get_weights()) * (1 - self.TAU))
self.target_critic.set_weights(
np.array(self.critic.get_weights()) * self.TAU +
np.array(self.target_critic.get_weights()) * (1 - self.TAU))
"""
# Method 2:
new_weights = []
target_variables = self.target_critic.weights
for i, variable in enumerate(self.critic.weights):
new_weights.append(variable * self.TAU + target_variables[i] * (1 - self.TAU))
self.target_critic.set_weights(new_weights)
new_weights = []
target_variables = self.target_actor.weights
for i, variable in enumerate(self.actor.weights):
new_weights.append(variable * self.TAU + target_variables[i] * (1 - self.TAU))
self.target_actor.set_weights(new_weights)
"""
def train_step(self):
s_batch, a_batch, r_batch, d_batch, s2_batch = self.replay_buffer.sample_batch(
self.minibatch_size)
"""
mu_prime = self.target_actor(s2_batch) # predictions by target actor
Q_prime = self.target_critic([s2_batch, mu_prime]) # predictions by target critic
y = np.zeros_like(Q_prime)
for k in range(self.minibatch_size):
if d_batch[k]:
y[k] = r_batch[k]
else:
y[k] = r_batch[k] + self.GAMMA * Q_prime[k]
# y = r_batch + gamma * Q_prime
checkpoint_path = "training/cp_critic.ckpt"
checkpoint_dir = os.path.dirname(checkpoint_path)
# Create a callback that saves the model's weights
cp_callback1 = tf.keras.callbacks.ModelCheckpoint(filepath=checkpoint_dir,
save_weights_only=True,
verbose=1)
self.critic.train_on_batch([s_batch, a_batch], y)
# self.critic.fit([s_batch, a_batch], y, verbose=0, steps_per_epoch=8, callbacks=[cp_callback1])
with tf.GradientTape(persistent=True) as tape:
a = self.actor(s_batch)
tape.watch(a)
theta = self.actor.trainable_variables
q = self.critic([s_batch, a])
dq_da = tape.gradient(q, a)
da_dtheta = tape.gradient(a, theta, output_gradients=-dq_da)
self.actor_opt.apply_gradients(zip(da_dtheta, self.actor.trainable_variables))
"""
with tf.GradientTape() as tape:
target_actions = self.target_actor(s2_batch)
y = r_batch + self.GAMMA * self.target_critic(
[s2_batch, target_actions])
critic_value = self.critic([s_batch, a_batch])
critic_loss = tf.math.reduce_mean(tf.math.square(y - critic_value))
critic_grad = tape.gradient(critic_loss,
self.critic.trainable_variables)
self.critic_opt.apply_gradients(
zip(critic_grad, self.critic.trainable_variables))
with tf.GradientTape() as tape:
actions = self.actor(s_batch)
q = self.critic([s_batch, actions]) # critic_value
# Used `-value` as we want to maximize the value given
# by the critic for our actions
actor_loss = -tf.math.reduce_mean(q)
actor_grad = tape.gradient(actor_loss, self.actor.trainable_variables)
self.actor_opt.apply_gradients(
zip(actor_grad, self.actor.trainable_variables))
self.update_target()
return np.mean(q)
def policy(self, s):
# since batch normalization is done on self.actor, it is multiplied with upper_bound
if s.ndim == 1:
s = s[None, :]
action = self.actor(s) * self.upper_bound + self.ou_noise()
action = np.clip(action, self.lower_bound, self.upper_bound)
return action
def train(self):
# To store reward history of each episode
ep_reward_list = []
# To store average reward history of last few episodes
avg_reward_list = []
monitor = Monitor([1, 1], titles=['Reward', 'Loss'], log=2)
with Loop_handler(
) as interruption: # to properly save even if ctrl+C is pressed
for eps in range(self.EPISODES):
episode_reward = 0
s = self.env.reset()
"""
if an env is created using the "gym.make" method, it will terminate after 200 steps
"""
for t in range(self.MAX_TIME_STEPS):
# done = False
# while not done:
if self.render:
self.env.render()
a = self.policy(s)
s_, r, done, _ = self.env.step(a)
self.replay_buffer.add(np.reshape(s, (self.s_dim, )),
np.reshape(a, (self.a_dim, )),
r, done,
np.reshape(s_, (self.s_dim, )))
episode_reward += r
if self.replay_buffer.size() > self.minibatch_size:
q = self.train_step()
s = s_.reshape(1, -1)
if interruption():
break
ep_reward_list.append(episode_reward)
# Mean of last 40 episodes
avg_reward = np.mean(ep_reward_list[-40:])
print("Episode * {} * Avg Reward is ==> {}".format(
eps, avg_reward))
avg_reward_list.append(avg_reward)
monitor.add_data(avg_reward, q)
self.save_weights(
save_name=self.save_name) # if you want to save weights
self.plot_results(avg_reward=avg_reward_list, train=True)
def save_weights(self, save_name='final_weights'):
self.actor.save_weights("training/%s_actor.h5" % save_name)
self.critic.save_weights("training/%s_critic.h5" % save_name)
self.target_actor.save_weights("training/%s_target_actor.h5" %
save_name)
self.target_critic.save_weights("training/%s_target_critic.h5" %
save_name)
# to save in other format
self.target_actor.save_weights('training/%s_actor_weights' % save_name,
save_format='tf')
self.target_critic.save_weights('training/%s_critic_weights' %
save_name,
save_format='tf')
print('Training completed and network weights saved')
# For evaluation of the policy learned
def collect_data(self, act_net, iterations=1000):
a_all, states_all = [], []
obs = self.env.reset()
for t in range(iterations):
obs = np.squeeze(obs)
if obs.ndim == 1:
a = act_net(obs[None, :])
else:
a = act_net(obs)
obs, _, done, _ = self.env.step(a)
states_all.append(obs)
a_all.append(a)
# self.env.render() # Uncomment this to see the actor in action (But not in python notebook)
# if done:
# break
states = np.squeeze(
np.array(states_all)) # cos(theta), sin(theta), theta_dot
a_all = np.squeeze(np.array(a_all))
return states, a_all
def plot_results(self,
avg_reward=None,
actions=None,
states=None,
train=False,
title=None):
# An additional way to visualize the avg episode rewards
if train:
plt.figure()
plt.plot(avg_reward)
plt.xlabel("Episode")
plt.ylabel("Avg. Epsiodic Reward")
plt.show()
else: # work only for Pendulum-v0 environment
fig, ax = plt.subplots(3, sharex=True)
theta = np.arctan2(states[:, 1], states[:, 0])
ax[0].set_ylabel('u')
ax[0].plot(np.squeeze(actions))
ax[1].set_ylabel(u'$\\theta$')
ax[1].plot(theta)
# ax[1].plot(states[:, 0])
ax[2].set_ylabel(u'$\omega$')
ax[2].plot(states[:, 2]) # ang velocity
fig.canvas.set_window_title(title)
class DDPG:
def __init__(
self,
obs_dim,
action_dim,
action_gain,
actor_learning_rate=0.0001,
critic_learning_rate=0.001,
gamma=0.99,
tau=0.001,
):
self.obs_dim = obs_dim
self.action_dim = action_dim
self.gamma = gamma
self.tau = tau
# make main networks
self.actor = Actor(obs_dim, action_dim, action_gain,
actor_learning_rate)
self.critic = Critic(obs_dim, action_dim, critic_learning_rate)
# make target networks
self.target_actor = Actor(obs_dim, action_dim, action_gain)
self.target_actor.model.set_weights(self.actor.model.get_weights())
self.target_critic = Critic(obs_dim, action_dim)
self.target_critic.model.set_weights(self.critic.model.get_weights())
def act(self, obs):
return self.actor.act(obs)[0]
@tf.function
def update_networks(self, batch):
""" runs all updates from provided training batch """
s, a, r, t, next_s = (tf.cast(i, tf.float32) for i in batch)
self.update_critic(s, a, r, next_s)
self.update_actor(s, a, r, next_s)
self.update_target(self.actor.model, self.target_actor.model)
self.update_target(self.critic.model, self.target_critic.model)
@tf.function
def update_critic(self, s, a, r, next_s):
""" minimize td-loss from target """
# td estimate based on targets' behavior
target_future_actions = self.target_actor.act(next_s)
target_future_qs = self.target_critic.estimate_q(
next_s, target_future_actions)
target_current_qs = r + self.gamma * target_future_qs
# update main critic
main_current_qs = self.critic.model([s, a])
loss = keras.losses.mse(target_current_qs, main_current_qs)
model_vars = self.critic.model.trainable_variables
dloss_dcrit = tf.gradients(loss, model_vars)
self.critic.optimizer.apply_gradients(zip(dloss_dcrit, model_vars))
@tf.function
def update_actor(self, s, a, r, next_s):
""" dq_dtheta = dq_da * da_dtheta"""
# first, finding dq_da
proposed_a = self.actor.model(s)
q = self.critic.model([s, proposed_a])
dq_da = tf.gradients(q, proposed_a)[0]
# second, finding dq_da * da_dtheta
model_vars = self.actor.model.trainable_variables
dq_dtheta = tf.gradients(proposed_a, model_vars, grad_ys=-dq_da)
# updating the model
self.actor.optimizer.apply_gradients(zip(dq_dtheta, model_vars))
@tf.function
def update_target(self, main_model, target_model):
""" target = tau*main + (1-tau)*target """
for model_weight, target_weight in zip(main_model.weights,
target_model.weights):
target_weight.assign(self.tau * model_weight +
(1 - self.tau) * target_weight)
def save_model(self, save_dir):
""" saves the main and target networks"""
self.actor.model.save_weights(os.path.join(save_dir, "actor"))
self.critic.model.save_weights(os.path.join(save_dir, "critic"))
self.target_actor.model.save_weights(
os.path.join(save_dir, "target_actor"))
self.target_critic.model.save_weights(
os.path.join(save_dir, "target_critic"))
class DDPG:
"""docstring for DDPG"""
def __init__(self, env, time_steps, hidden_dim):
self.name = 'DDPG' # name for uploading results
self.scale = env.asset
self.unit = env.unit
self.seed = env.rd_seed
self.time_dim = time_steps
self.state_dim = env.observation_space.shape[1]
self.action_dim = env.action_space.shape[0]
self.batch_size = 64
self.memory_size = self.time_dim + self.batch_size * 10
self.start_size = self.time_dim + self.batch_size * 2
# Initialise actor & critic networks
self.actor_network = Actor(self.time_dim, self.state_dim,
self.action_dim, hidden_dim)
self.critic_network = Critic(self.time_dim, self.state_dim,
self.action_dim, hidden_dim)
# Initialize replay buffer
self.replay_state = torch.zeros(
(self.start_size - 1, 3, self.state_dim), device=cuda)
self.replay_next_state = torch.zeros(
(self.start_size - 1, 3, self.state_dim), device=cuda)
self.replay_action = torch.zeros(
(self.start_size - 1, 1, self.state_dim), device=cuda)
self.replay_reward = torch.zeros((self.start_size - 1, ), device=cuda)
# Initialize a random process the Ornstein-Uhlenbeck process for action exploration
self.exploration_noise = OUNoise(self.action_dim,
sigma=0.01 / self.action_dim)
self.initial()
def initial(self):
self.steps = 0
self.action = torch.zeros(self.action_dim, device=cuda)
self.replay_state = torch.zeros(
(self.start_size - 1, 3, self.state_dim), device=cuda)
self.replay_next_state = torch.zeros(
(self.start_size - 1, 3, self.state_dim), device=cuda)
self.replay_action = torch.zeros((self.start_size - 1, self.state_dim),
device=cuda)
self.replay_reward = torch.zeros((self.start_size - 1, ), device=cuda)
def train_on_batch(self):
# Sample a random minibatch of N transitions from replay buffer
sample = torch.randint(self.time_dim,
self.replay_reward.shape[0], [self.batch_size],
device=cuda)
index = torch.stack([sample - i for i in range(self.time_dim, 0, -1)
]).t().reshape(-1)
state_data = min_max_scale(self.replay_state[:, 0, :])
amount_data = min_max_scale(self.replay_state[:, 2, :])
next_state_data = min_max_scale(self.replay_next_state[:, 0, :])
next_amount_data = min_max_scale(self.replay_next_state[:, 2, :])
state_batch = torch.index_select(state_data, 0,
index).view(self.batch_size, -1)
amount_data = torch.index_select(amount_data, 0,
sample).view(self.batch_size, -1)
state_batch = torch.cat([state_batch, amount_data], dim=1)
next_state_batch = torch.index_select(next_state_data, 0,
index).view(self.batch_size, -1)
next_amount_data = torch.index_select(next_amount_data, 0,
sample).view(
self.batch_size, -1)
next_state_batch = torch.cat([next_state_batch, next_amount_data],
dim=1)
action_batch = torch.index_select(self.replay_action / self.unit, 0,
sample)
reward_batch = torch.index_select(self.replay_reward, 0, sample)
# Calculate y_batch
next_action_batch = self.actor_network.target_action(next_state_batch)
q_batch = self.critic_network.target_q(next_action_batch,
next_state_batch)
y_batch = torch.add(reward_batch, q_batch, alpha=GAMMA).view(-1, 1)
# train actor-critic by target loss
self.actor_network.train(
self.critic_network.train(y_batch, action_batch, state_batch))
# Update target networks by soft update
self.actor_network.update_target()
self.critic_network.update_target()
def perceive(self, state, action, reward, next_state, done):
if self.steps < self.start_size - 1:
self.replay_state[self.steps] = state
self.replay_next_state[self.steps] = next_state
self.replay_action[self.steps] = action
self.replay_reward[self.steps] = reward
else:
if self.steps >= self.memory_size:
self.replay_state = self.replay_state[1:]
self.replay_next_state = self.replay_next_state[1:]
self.replay_action = self.replay_action[1:]
self.replay_reward = self.replay_reward[1:]
self.replay_state = torch.cat(
(self.replay_state, state.unsqueeze(0)), dim=0)
self.replay_next_state = torch.cat(
(self.replay_next_state, next_state.unsqueeze(0)), dim=0)
self.replay_action = torch.cat(
(self.replay_action, action.unsqueeze(0)), dim=0)
self.replay_reward = torch.cat(
(self.replay_reward, reward.unsqueeze(0)), dim=0)
self.steps += 1
def act(self, next_state, portfolio):
if self.steps > self.start_size:
next_state_data = min_max_scale(
self.replay_next_state[:, 0, :])[-self.time_dim:].view(1, -1)
next_amount_data = min_max_scale(
self.replay_next_state[:, 2, :])[-1].view(1, -1)
next_state_data = torch.cat([next_state_data, next_amount_data],
dim=1)
self.train_on_batch()
allocation = self.actor_network.target_action(
next_state_data).data.view(-1)
allocation += torch.tensor(self.exploration_noise.noise().tolist(),
device=cuda)
allocation[allocation < 0] = 0
allocation /= sum(allocation)
allocation = torch.floor(portfolio * allocation /
next_state[1, :] / self.unit) * self.unit
self.action = allocation
return self.action.clone()
class Agent():
def __init__(self,
state_size,
action_size,
action_sigma=0.1,
memory_size=1000000,
batch=128,
sigma=0.2,
noise_clip=0.5,
gamma=0.99,
update_frequency=2,
seed=0):
'''
TD3 Agent
:param state_size: State Dimension
:param action_size: Action dimension
:param action_sigma: standard deviation of the noise to be added to the action
:param memory_size:
:param batch:
:param sigma: Standard deviation of the noise to be added to the target function (Chapter 5.3 of TD3 Paper)
:param noise_clip: How much noise to allow
:param gamma:
:param update_frequency:
:param seed:
'''
self.state_size = state_size
self.action_size = action_size
self.action_sigma = action_sigma
self.sigma = sigma
self.noise_clip = noise_clip
self.gamma = gamma
self.update_frequency = update_frequency
self.seed = seed
self.actor = Actor(self.state_size, self.action_size).to(device)
self.critic0 = Critic(self.state_size, self.action_size).to(device)
#second Critic as described in the paper
# https: // arxiv.org / pdf / 1802.09477.pdf
self.critic1 = Critic(self.state_size, self.action_size).to(device)
self.target_actor = Actor(self.state_size, self.action_size).to(device)
self.target_critic0 = Critic(self.state_size,
self.action_size).to(device)
# second Critic as described in the paper
# https: // arxiv.org / pdf / 1802.09477.pdf
self.target_critic1 = Critic(self.state_size,
self.action_size).to(device)
self.memory = ReplayBuffer(memory_size, batch, seed=seed)
self.actor_optimizer = Adam(self.actor.parameters(), lr=ACTOR_LR)
self.critic0_optimizer = Adam(self.critic0.parameters(), lr=VALUE0_LR)
self.critic1_optimizer = Adam(self.critic1.parameters(), lr=VALUE1_LR)
self.soft_update(self.actor, self.target_actor, 1)
self.soft_update(self.critic0, self.target_critic0, 1)
self.soft_update(self.critic1, self.target_critic1, 1)
def act(self, state, epsilon=True):
state = torch.from_numpy(np.asarray(state)).float().to(device)
self.actor.eval()
with torch.no_grad():
action = self.actor.forward(state).cpu().data.numpy()
self.actor.train()
if epsilon:
#if we want to inject some noise
noise = np.random.normal(0, self.action_sigma, action.shape[0])
action += noise
return action
def update(self, step):
'''
#https: // arxiv.org / pdf / 1802.09477.pdf
the function is very similar to typical DDPG algorithm, except for
1) we have 2 critics to update
2) we take the min of the 2 values critics output
3) Has modified Target network with noise injected into it (Chapter 5.3 of the paper)
4) We delay updating the actor by certain steps
:param step: how often to update the actor
:return:
'''
state, action, reward, next_state, done = self.memory.sample()
# ---------------------------- update critic ---------------------------- #
# Get predicted next-state actions and Q values from target models
next_state_action = self.target_actor(next_state)
#sample a random noise
noise = Normal(torch.zeros(self.action_size), self.sigma).sample()
noise = torch.clamp(noise, -self.noise_clip,
self.noise_clip).to(device)
next_state_action += noise
target_Q0 = self.target_critic0(next_state, next_state_action)
target_Q1 = self.target_critic1(next_state, next_state_action)
target_Q = torch.min(target_Q0, target_Q1)
target_value = reward + self.gamma * target_Q * (1.0 - done)
expected_Q0 = self.critic0(state, action)
expected_Q1 = self.critic1(state, action)
critic_0_loss = F.mse_loss(expected_Q0, target_value.detach())
critic_1_loss = F.mse_loss(expected_Q1, target_value.detach())
self.critic0_optimizer.zero_grad()
critic_0_loss.backward()
self.critic0_optimizer.step()
self.critic1_optimizer.zero_grad()
critic_1_loss.backward()
self.critic1_optimizer.step()
# ---------------------------- update actor ---------------------------- #
# Compute actor loss
#as mentioned in the paper, we delay updating the actor network.
if step % self.update_frequency == 0:
actor_loss = self.critic0.forward(state, self.actor.forward(state))
actor_loss = -actor_loss.mean()
self.actor_optimizer.zero_grad()
actor_loss.backward()
self.actor_optimizer.step()
# ----------------------- update target networks ------------------- #
self.soft_update(self.critic0, self.target_critic0, TRANSFER_RATE)
self.soft_update(self.critic1, self.target_critic1, TRANSFER_RATE)
self.soft_update(self.actor, self.target_actor, TRANSFER_RATE)
def soft_update(self, local_model, target_model, tao):
for target_param, local_param in zip(target_model.parameters(),
local_model.parameters()):
target_param.data.copy_(tao * local_param.data +
(1.0 - tao) * target_param.data)
def add_to_memory(self, state, action, reward, next_state, done):
self.memory.add(state, action, reward, next_state, done)
class ActorCriticExperienceReplay(object):
def __init__(self, env):
self.MEMORY_SIZE = 200
self.BATCH_SIZE = 10
LR_A = 0.001 # learning rate for actor
LR_C = 0.01 # learning rate for critic
num_features = env.observation_space.shape[0]
num_actions = env.action_space.shape[0]
self.action_space = env.action_space
sess = tf.Session()
self.actor = Actor(
sess,
n_features=num_features,
action_bound=[env.action_space.low[0], env.action_space.high[0]],
lr=LR_A)
self.critic = Critic(
sess, n_features=num_features, lr=LR_C
) # we need a good teacher, so the teacher should learn faster than the actor
sess.run(tf.global_variables_initializer())
self.replay_memory = []
def get_action(self, state, episode_percentage):
# Sometimes pick random action to explore
if np.random.random() < self.get_exploration_prob(episode_percentage):
return self.action_space.sample()
else:
return self.actor.choose_action(state)[0]
def get_exploration_prob(self, episode_percentage):
return -1 * (episode_percentage**2) + 1
# return -1 * (episode_percentage - 1) ** 3
def update(self, state, action, reward, new_state):
td_error = self.critic.learn(
state, reward,
new_state) # gradient = grad[r + gamma * V(s_) - V(s)]
self.actor.learn(
state, action,
td_error) # true_gradient = grad[logPi(s,a) * td_error]
# Add to replay memory
self.replay_memory.append((state, action, reward, new_state))
if len(self.replay_memory) >= self.MEMORY_SIZE:
self.replay_memory.pop(0)
# Learn from replayed memories
if np.random.random() < 0.5 and len(
self.replay_memory) > self.BATCH_SIZE:
minibatch = random.sample(self.replay_memory, self.BATCH_SIZE)
for (batch_state, batch_action, batch_reward,
batch_new_state) in minibatch:
td_error = self.critic.learn(batch_state, batch_reward,
batch_new_state)
self.actor.learn(batch_state, batch_action, td_error)
def get_name(self):
return 'ActorCritic_ExperienceReplay'
class DDPGHedgingAgent:
"""DDPGAgent interacting with environment.
Attribute:
env (gym.Env): openAI Gym environment
actor (nn.Module): target actor model to select actions
actor_target (nn.Module): actor model to predict next actions
actor_optimizer (Optimizer): optimizer for training actor
critic (nn.Module): critic model to predict state values
critic_target (nn.Module): target critic model to predict state values
critic_optimizer (Optimizer): optimizer for training critic
memory (ReplayBuffer): replay memory to store transitions
batch_size (int): batch size for sampling
gamma (float): discount factor
tau (float): parameter for soft target update
initial_random_episode (int): initial random action steps
noise (OUNoise): noise generator for exploration
device (torch.device): cpu / gpu
transition (list): temporory storage for the recent transition
total_step (int): total step numbers
is_test (bool): flag to show the current mode (train / test)
"""
def __init__(self,
env: gym.Env,
memory_size: int,
batch_size: int,
ou_noise_theta: float,
ou_noise_sigma: float,
gamma: float = 0.99,
tau: float = 5e-3,
initial_random_episode: int = 1e4,
name_cases='myproject'):
""" Initialize. """
# Logger
self.wandb = wandb.init(project=name_cases)
obs_dim = env.observation_space.shape[0]
action_dim = env.action_space.shape[0]
self.env = env
self.memory = ReplayBuffer(memory_size)
self.batch_size = batch_size
self.gamma = gamma
self.tau = tau
self.initial_random_episode = initial_random_episode
# noise
self.noise = OUNoise(
action_dim,
theta=ou_noise_theta,
sigma=ou_noise_sigma,
)
# device: cpu / gpu
self.device = torch.device(
"cuda" if torch.cuda.is_available() else "cpu")
print(self.device)
# networks
self.actor = Actor(obs_dim, action_dim).to(self.device)
self.actor_target = Actor(obs_dim, action_dim).to(self.device)
self.actor_target.load_state_dict(self.actor.state_dict())
self.critic = Critic(obs_dim + action_dim).to(self.device)
self.critic_target = Critic(obs_dim + action_dim).to(self.device)
self.critic_target.load_state_dict(self.critic.state_dict())
# optimizer
self.actor_optimizer = optim.Adam(self.actor.parameters(), lr=3e-4)
self.critic_optimizer = optim.Adam(self.critic.parameters(), lr=1e-3)
# transition to store in memory
self.transition = list()
# total steps count
self.total_step = 0
# mode: train / test
self.is_test = False
self.populate(self.initial_random_episode)
def populate(self, eps: int = 100) -> None:
"""
Carries out several random steps through the environment to initially fill
up the replay buffer with experiences
Args:
steps: number of random steps to populate the buffer with
"""
if not self.is_test:
print("Populate Replay Buffer... ")
kbar = pkbar.Kbar(target=eps, width=20)
state = self.env.reset()
for i in range(eps):
while True:
# Get action from sample space
selected_action = self.env.action_space.sample()
# selected_action = 0
noise = self.noise.sample()
selected_action = np.clip(selected_action + noise, -1.0,
1.0)
next_state, reward, done, _ = self.env.step(
selected_action)
self.transition = [
state, selected_action, reward, next_state,
int(done)
]
self.memory.append(Experience(*self.transition))
state = next_state
if done:
state = self.env.reset()
break
kbar.add(1)
# self.scaler = self.memory.standar_scaler()
@torch.no_grad()
def select_action(self, state: np.ndarray) -> np.ndarray:
"""Select an action from the input state."""
state_s = self.scaler.transform([state])
selected_action = self.actor(
torch.FloatTensor(state_s).to(self.device)).item()
# add noise for exploration during training
if not self.is_test:
noise = self.noise.sample()
selected_action = np.clip(selected_action + noise, -1.0, 1.0)
self.transition = [state, selected_action]
return selected_action
def step(self, action: np.ndarray) -> Tuple[np.ndarray, np.float64, bool]:
"""Take an action and return the response of the env."""
next_state, reward, done, _ = self.env.step(action)
if not self.is_test:
self.transition += [reward, next_state, int(done)]
self.memory.append(Experience(*self.transition))
return next_state, reward, done
def update_model(self) -> torch.Tensor:
""" Update the model by gradient descent.
Change the loss in to mean variance optimization
"""
device = self.device # for shortening the following lines
state, action, reward, next_state, done = self.memory.sample(
self.batch_size, self.device)
state = torch.FloatTensor(self.scaler.transform(state)).to(device)
next_state = torch.FloatTensor(
self.scaler.transform(next_state)).to(device)
# state = state.to(device)
# next_state = next_state.to(device)
action = action.to(device)
reward = reward.to(device)
done = done.to(device)
masks = 1 - done
next_action = self.actor_target(next_state)
next_value = self.critic_target(next_state, next_action)
curr_return = reward.reshape(
-1, 1) + self.gamma * next_value * masks.reshape(-1, 1)
# train critic
values = self.critic(state, action)
critic_loss = F.mse_loss(values, curr_return)
self.critic_optimizer.zero_grad()
critic_loss.backward()
self.critic_optimizer.step()
# Freeze Q-network so you don't waste computational effort
# computing gradients for it during the policy learning step.
for p in self.critic.parameters():
p.requires_grad = False
# train actor
q_values = self.critic(state, self.actor(state))
actor_loss = -q_values.mean()
# actor_loss = 0.5 * q_values.std() ** 2
self.actor_optimizer.zero_grad()
actor_loss.backward()
self.actor_optimizer.step()
for p in self.critic.parameters():
p.requires_grad = True
# target update
self._target_soft_update()
return actor_loss.data, critic_loss.data
def train(self, num_frames: int, plotting_interval: int = 200):
"""Train the agent."""
self.is_test = False
state = self.env.reset()
actor_losses = []
critic_losses = []
scores = []
score = 0
print("Training...")
kbar = pkbar.Kbar(target=num_frames, width=20)
for self.total_step in range(1, num_frames + 1):
action = self.select_action(state)
next_state, reward, done = self.step(action)
state = next_state
score += reward
# if episode ends
if done:
state = self.env.reset()
scores.append(score)
score = 0
self._plot(
self.total_step,
scores,
actor_losses,
critic_losses,
)
# if training is ready
if (len(self.memory) >= self.batch_size): # and
actor_loss, critic_loss = self.update_model()
actor_losses.append(actor_loss)
critic_losses.append(critic_loss)
kbar.add(1)
self.env.close()
def test(self):
"""Test the agent."""
self.is_test = True
state = self.env.reset()
done = False
score = 0
while not done:
action = self.select_action(state)
next_state, reward, done = self.step(action)
state = next_state
score += reward
self.env.close()
return score
def _target_soft_update(self):
"""Soft-update: target = tau*local + (1-tau)*target."""
tau = self.tau
for t_param, l_param in zip(self.actor_target.parameters(),
self.actor.parameters()):
t_param.data.copy_(tau * l_param.data + (1.0 - tau) * t_param.data)
for t_param, l_param in zip(self.critic_target.parameters(),
self.critic.parameters()):
t_param.data.copy_(tau * l_param.data + (1.0 - tau) * t_param.data)
def _plot(
self,
frame_idx: int,
scores: List[float],
actor_losses: List[float],
critic_losses: List[float],
):
"""Plot the training progresses."""
self.wandb.log({
'frame': frame_idx,
'score': scores[-1],
'actor_loss': actor_losses[-1],
'critic_loss': critic_losses[-1]
})
class DDPGAGENT:
def __init__(self, state_size, action_size, random_seed):
self.state_size = state_size
self.action_size = action_size
self.seed = random.seed(random_seed)
self.epsilon = EPS
#--- actor -----#
self.actor_local = Actor(state_size, action_size,
random_seed).to(device)
self.actor_target = Actor(state_size, action_size,
random_seed).to(device)
self.actor_optimizer = optim.Adam(self.actor_local.parameters(),
lr=1e-3)
#---- critic -----#
self.critic_local = Critic(state_size, action_size,
random_seed).to(device)
self.critic_target = Critic(state_size, action_size,
random_seed).to(device)
self.critic_optimizer = optim.Adam(self.critic_local.parameters(),
lr=1e-3,
weight_decay=0)
self.noise = OUNoise(action_size, random_seed)
self.memory = ReplayBuffer(action_size, BUFFER_SIZE, BATCH_SIZE,
random_seed)
#self.timestep = 0
def step(self, state, action, reward, next_state, done, timestep):
self.memory.add_experience(state, action, reward, next_state, done)
#self.timestep = (self.timestep + 1) % UPDATE_EVERY
if len(self.memory) > BATCH_SIZE and timestep % UPDATE_EVERY == 0:
for _ in range(LEARN_NUM):
xp = self.memory.sample()
self.learn(xp, GAMMA) #GAMMA VALUE 0.99
def act(self, state, noise_accumulate=True):
state = torch.from_numpy(state).float().to(device)
self.actor_local.eval()
with torch.no_grad():
action = self.actor_local(state).cpu().data.numpy()
self.actor_local.train()
#Epsilon greedy selection
if noise_accumulate:
action += self.epsilon * self.noise.sample()
return np.clip(action, -1, 1)
def reset(self):
self.noise.reset_internal_state()
def learn(self, xp, gamma):
states, actions, rewards, next_states, dones = xp
#---configuring critic and computation of loss with help of MSE
actions_nxt = self.actor_target(next_states)
q_target_next = self.critic_target(next_states, actions_nxt)
q_target = rewards + (gamma * q_target_next * (1 - dones))
q_expected = self.critic_local(states, actions)
#MSE LOSS
critic_loss = F.mse_loss(q_expected, q_target)
self.critic_optimizer.zero_grad()
critic_loss.backward()
# Clips gradient norm of an iterable of parameters
torch.nn.utils.clip_grad_norm_(self.critic_local.parameters(), 1)
self.critic_optimizer.step()
#---configuring actor and computation of loss with help of MSE
actor_predicted = self.actor_local(states)
actor_loss = -self.critic_local(states, actor_predicted).mean()
self.actor_optimizer.zero_grad()
actor_loss.backward()
self.actor_optimizer.step()
self.soft_update(self.critic_local, self.critic_target, TAU)
self.soft_update(self.actor_local, self.actor_target, TAU)
self.epsilon -= 1e-6
self.noise.reset_internal_state()
def soft_update(self, local_model, target_model, tau):
for target_param, local_param in zip(target_model.parameters(),
local_model.parameters()):
target_param.data.copy_(tau * local_param.data +
(1.0 - tau) * target_param.data)