我在用于深度强化学习的 pyhon 代码中收到此错误，“No step set via 'step' argument or tf.summary.experimental.set_step()” 这是使用 tensorflow 进行强化学习的代码，我刚刚开始这个话题并且不太了解它，如果有人可以帮助我找出我错在哪里，那将是一个很大的帮助。
这是代码:
import numpy as np
import keras.backend.tensorflow_backend as backend
from keras.models import Sequential
from keras.layers import Dense, Dropout, Conv2D, MaxPooling2D, Activation, Flatten
from keras.optimizers import Adam
from keras.callbacks import TensorBoard
import tensorflow as tf
from collections import deque
import time
import random
from tqdm import tqdm
import os
from PIL import Image
import cv2
DISCOUNT = 0.99
REPLAY_MEMORY_SIZE = 50_000 # How many last steps to keep for model training
MIN_REPLAY_MEMORY_SIZE = 1_000 # Minimum number of steps in a memory to start training
MINIBATCH_SIZE = 64 # How many steps (samples) to use for training
UPDATE_TARGET_EVERY = 5 # Terminal states (end of episodes)
MODEL_NAME = '2x256'
MIN_REWARD = -200 # For model save
MEMORY_FRACTION = 0.20
# Environment settings
EPISODES = 20
# Exploration settings
epsilon = 1 # not a constant, going to be decayed
EPSILON_DECAY = 0.99975
MIN_EPSILON = 0.001
# Stats settings
AGGREGATE_STATS_EVERY = 50 # episodes
SHOW_PREVIEW = False
class Blob:
def __init__(self, size):
self.size = size
self.x = np.random.randint(0, size)
self.y = np.random.randint(0, size)
def __str__(self):
return f"Blob ({self.x}, {self.y})"
def __sub__(self, other):
return (self.x-other.x, self.y-other.y)
def __eq__(self, other):
return self.x == other.x and self.y == other.y
def action(self, choice):
'''
Gives us 9 total movement options. (0,1,2,3,4,5,6,7,8)
'''
if choice == 0:
self.move(x=1, y=1)
elif choice == 1:
self.move(x=-1, y=-1)
elif choice == 2:
self.move(x=-1, y=1)
elif choice == 3:
self.move(x=1, y=-1)
elif choice == 4:
self.move(x=1, y=0)
elif choice == 5:
self.move(x=-1, y=0)
elif choice == 6:
self.move(x=0, y=1)
elif choice == 7:
self.move(x=0, y=-1)
elif choice == 8:
self.move(x=0, y=0)
def move(self, x=False, y=False):
# If no value for x, move randomly
if not x:
self.x += np.random.randint(-1, 2)
else:
self.x += x
# If no value for y, move randomly
if not y:
self.y += np.random.randint(-1, 2)
else:
self.y += y
# If we are out of bounds, fix!
if self.x < 0:
self.x = 0
elif self.x > self.size-1:
self.x = self.size-1
if self.y < 0:
self.y = 0
elif self.y > self.size-1:
self.y = self.size-1
class BlobEnv:
SIZE = 10
RETURN_IMAGES = True
MOVE_PENALTY = 1
ENEMY_PENALTY = 300
FOOD_REWARD = 25
OBSERVATION_SPACE_VALUES = (SIZE, SIZE, 3) # 4
ACTION_SPACE_SIZE = 9
PLAYER_N = 1 # player key in dict
FOOD_N = 2 # food key in dict
ENEMY_N = 3 # enemy key in dict
# the dict! (colors)
d = {1: (255, 175, 0),
2: (0, 255, 0),
3: (0, 0, 255)}
def reset(self):
self.player = Blob(self.SIZE)
self.food = Blob(self.SIZE)
while self.food == self.player:
self.food = Blob(self.SIZE)
self.enemy = Blob(self.SIZE)
while self.enemy == self.player or self.enemy == self.food:
self.enemy = Blob(self.SIZE)
self.episode_step = 0
if self.RETURN_IMAGES:
observation = np.array(self.get_image())
else:
observation = (self.player-self.food) + (self.player-self.enemy)
return observation
def step(self, action):
self.episode_step += 1
self.player.action(action)
#### MAYBE ###
#enemy.move()
#food.move()
##############
if self.RETURN_IMAGES:
new_observation = np.array(self.get_image())
else:
new_observation = (self.player-self.food) + (self.player-self.enemy)
if self.player == self.enemy:
reward = -self.ENEMY_PENALTY
elif self.player == self.food:
reward = self.FOOD_REWARD
else:
reward = -self.MOVE_PENALTY
done = False
if reward == self.FOOD_REWARD or reward == -self.ENEMY_PENALTY or self.episode_step >= 200:
done = True
return new_observation, reward, done
def render(self):
img = self.get_image()
img = img.resize((300, 300)) # resizing so we can see our agent in all its glory.
cv2.imshow("image", np.array(img)) # show it!
cv2.waitKey(1)
# FOR CNN #
def get_image(self):
env = np.zeros((self.SIZE, self.SIZE, 3), dtype=np.uint8) # starts an rbg of our size
env[self.food.x][self.food.y] = self.d[self.FOOD_N] # sets the food location tile to green color
env[self.enemy.x][self.enemy.y] = self.d[self.ENEMY_N] # sets the enemy location to red
env[self.player.x][self.player.y] = self.d[self.PLAYER_N] # sets the player tile to blue
img = Image.fromarray(env, 'RGB') # reading to rgb. Apparently. Even tho color definitions are bgr. ???
return img
env = BlobEnv()
# For stats
ep_rewards = [-200]
# For more repetitive results
random.seed(1)
np.random.seed(1)
#tf.set_random_seed(1)
# Memory fraction, used mostly when trai8ning multiple agents
#gpu_options = tf.GPUOptions(per_process_gpu_memory_fraction=MEMORY_FRACTION)
#backend.set_session(tf.Session(config=tf.ConfigProto(gpu_options=gpu_options)))
# Create models folder
if not os.path.isdir('models'):
os.makedirs('models')
# Own Tensorboard class
class ModifiedTensorBoard(TensorBoard):
# Overriding init to set initial step and writer (we want one log file for all .fit() calls)
def __init__(self, **kwargs):
super().__init__(**kwargs)
self.step = 1
self.writer = tf.summary.create_file_writer(self.log_dir)
# Overriding this method to stop creating default log writer
def set_model(self, model):
pass
# Overrided, saves logs with our step number
# (otherwise every .fit() will start writing from 0th step)
def on_epoch_end(self, epoch, logs=None):
self.update_stats(**logs)
# Overrided
# We train for one batch only, no need to save anything at epoch end
def on_batch_end(self, batch, logs=None):
pass
# Overrided, so won't close writer
def on_train_end(self, _):
pass
# Custom method for saving own metrics
# Creates writer, writes custom metrics and closes writer
def update_stats(self, **stats):
self._write_logs(stats, self.step)
# More or less the same writer as in Keras' Tensorboard callback
# Physically writes to the log files
def _write_logs(self, logs, index):
for name, value in logs.items():
if name in ['batch', 'size']:
continue
with self.writer.as_default():
tf.summary.scalar(name, value)
self.writer.flush()
# Agent class
class DQNAgent:
def __init__(self):
# Main model
self.model = self.create_model()
# Target network
self.target_model = self.create_model()
self.target_model.set_weights(self.model.get_weights())
# An array with last n steps for training
self.replay_memory = deque(maxlen=REPLAY_MEMORY_SIZE)
# Custom tensorboard object
self.tensorboard = ModifiedTensorBoard(log_dir="logs/{}-{}".format(MODEL_NAME, int(time.time())))
# Used to count when to update target network with main network's weights
self.target_update_counter = 0
def create_model(self):
model = Sequential()
model.add(Conv2D(256, (3, 3), input_shape=env.OBSERVATION_SPACE_VALUES)) # OBSERVATION_SPACE_VALUES = (10, 10, 3) a 10x10 RGB image.
model.add(Activation('relu'))
model.add(MaxPooling2D(pool_size=(2, 2)))
model.add(Dropout(0.2))
model.add(Conv2D(256, (3, 3)))
model.add(Activation('relu'))
model.add(MaxPooling2D(pool_size=(2, 2)))
model.add(Dropout(0.2))
model.add(Flatten()) # this converts our 3D feature maps to 1D feature vectors
model.add(Dense(64))
model.add(Dense(env.ACTION_SPACE_SIZE, activation='linear')) # ACTION_SPACE_SIZE = how many choices (9)
model.compile(loss="mse", optimizer=Adam(lr=0.001), metrics=['accuracy'])
return model
# Adds step's data to a memory replay array
# (observation space, action, reward, new observation space, done)
def update_replay_memory(self, transition):
self.replay_memory.append(transition)
# Trains main network every step during episode
def train(self, terminal_state, step):
# Start training only if certain number of samples is already saved
if len(self.replay_memory) < MIN_REPLAY_MEMORY_SIZE:
return
# Get a minibatch of random samples from memory replay table
minibatch = random.sample(self.replay_memory, MINIBATCH_SIZE)
# Get current states from minibatch, then query NN model for Q values
current_states = np.array([transition[0] for transition in minibatch])/255
current_qs_list = self.model.predict(current_states)
# Get future states from minibatch, then query NN model for Q values
# When using target network, query it, otherwise main network should be queried
new_current_states = np.array([transition[3] for transition in minibatch])/255
future_qs_list = self.target_model.predict(new_current_states)
X = []
y = []
# Now we need to enumerate our batches
for index, (current_state, action, reward, new_current_state, done) in enumerate(minibatch):
# If not a terminal state, get new q from future states, otherwise set it to 0
# almost like with Q Learning, but we use just part of equation here
if not done:
max_future_q = np.max(future_qs_list[index])
new_q = reward + DISCOUNT * max_future_q
else:
new_q = reward
# Update Q value for given state
current_qs = current_qs_list[index]
current_qs[action] = new_q
# And append to our training data
X.append(current_state)
y.append(current_qs)
# Fit on all samples as one batch, log only on terminal state
self.model.fit(np.array(X)/255, np.array(y), batch_size=MINIBATCH_SIZE, shuffle=False, callbacks=[self.tensorboard] if terminal_state else None)
# Update target network counter every episode
if terminal_state:
self.target_update_counter += 1
# If counter reaches set value, update target network with weights of main network
if self.target_update_counter > UPDATE_TARGET_EVERY:
self.target_model.set_weights(self.model.get_weights())
self.target_update_counter = 0
# Queries main network for Q values given current observation space (environment state)
def get_qs(self, state):
return self.model.predict(np.array(state).reshape(-1, *state.shape)/255)[0]
agent = DQNAgent()
# Iterate over episodes
for episode in tqdm(range(1, EPISODES + 1), ascii=True, unit='episodes'):
# Update tensorboard step every episode
agent.tensorboard.step = episode
# Restarting episode - reset episode reward and step number
episode_reward = 0
step = 1
# Reset environment and get initial state
current_state = env.reset()
# Reset flag and start iterating until episode ends
done = False
while not done:
# This part stays mostly the same, the change is to query a model for Q values
if np.random.random() > epsilon:
# Get action from Q table
action = np.argmax(agent.get_qs(current_state))
else:
# Get random action
action = np.random.randint(0, env.ACTION_SPACE_SIZE)
new_state, reward, done = env.step(action)
# Transform new continous state to new discrete state and count reward
episode_reward += reward
if SHOW_PREVIEW and not episode % AGGREGATE_STATS_EVERY:
env.render()
# Every step we update replay memory and train main network
agent.update_replay_memory((current_state, action, reward, new_state, done))
agent.train(done, step)
current_state = new_state
step += 1
# Append episode reward to a list and log stats (every given number of episodes)
ep_rewards.append(episode_reward)
if not episode % AGGREGATE_STATS_EVERY or episode == 1:
average_reward = sum(ep_rewards[-AGGREGATE_STATS_EVERY:])/len(ep_rewards[-AGGREGATE_STATS_EVERY:])
min_reward = min(ep_rewards[-AGGREGATE_STATS_EVERY:])
max_reward = max(ep_rewards[-AGGREGATE_STATS_EVERY:])
agent.tensorboard.update_stats(reward_avg=average_reward, reward_min=min_reward, reward_max=max_reward, epsilon=epsilon)
# Save model, but only when min reward is greater or equal a set value
if min_reward >= MIN_REWARD:
agent.model.save(f'models/{MODEL_NAME}__{max_reward:_>7.2f}max_{average_reward:_>7.2f}avg_{min_reward:_>7.2f}min__{int(time.time())}.model')
# Decay epsilon
if epsilon > MIN_EPSILON:
epsilon *= EPSILON_DECAY
epsilon = max(MIN_EPSILON, epsilon)
最佳答案
相当长的代码。保持简短，下次直接解决问题。
tf.summary.scalar 和 tf.summary.image 需要一个 step 值。也就是说，您正在编写这些值的时代。
尝试使用 tf.summary.scalar(name, value, step=epoch) 传递纪元。您在调用 def on_epoch_end(self, epoch, logs=None) 时获得此值，但您并未将其传递给以下函数。
有一个PR这似乎删除了 necessity of passing step .
关于python - 没有通过 'step' 参数或 tf.summary.experimental.set_step() 设置步骤，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/61961432/