class Agent:
def __init__(self):
self.states = [] # record position and action taken at the position
self.actions = ["up", "down", "left", "right"]
self.grid_world = GridWorld()
self.isEnd = self.grid_world.isEnd
self.lr = 0.2
self.exp_rate = 0.3
self.decay_gamma = 0.9
# initial Q values
self.Q_values = {}
for i in range(BOARD_ROWS):
for j in range(BOARD_COLS):
self.Q_values[(i, j)] = {}
for a in self.actions:
self.Q_values[(i, j)][a] = 0 # Q value is a dict of dict
def chooseAction(self):
# choose action with most expected value
mx_nxt_reward = 0
action = ""
if np.random.uniform(0, 1) <= self.exp_rate:
action = np.random.choice(self.actions)
else:
# greedy action
for a in self.actions:
current_position = self.grid_world.state
nxt_reward = self.Q_values[current_position][a]
if nxt_reward >= mx_nxt_reward:
action = a
mx_nxt_reward = nxt_reward
# print("current pos: {}, greedy aciton: {}".format(self.grid_world.state, action))
return action
def takeAction(self, action):
position = self.grid_world.nxtPosition(action)
# update GridWorld
return GridWorld(state=position)
def reset(self):
self.states = []
self.grid_world = GridWorld()
self.isEnd = self.grid_world.isEnd
def play(self, rounds=10):
i = 0
while i < rounds:
# to the end of game back propagate reward
if self.grid_world.isEnd:
# back propagate
reward = self.grid_world.giveReward()
for a in self.actions:
self.Q_values[self.grid_world.state][a] = reward
print("Game End Reward", reward)
for s in reversed(self.states):
current_q_value = self.Q_values[s[0]][s[1]]
reward = current_q_value + self.lr * (self.decay_gamma * reward - current_q_value)
self.Q_values[s[0]][s[1]] = round(reward, 3)
self.reset()
i += 1
else:
action = self.chooseAction()
# append trace
self.states.append([(self.grid_world.state), action])
print("current position {} action {}".format(self.grid_world.state, action))
# by taking the action, it reaches the next state
self.grid_world = self.takeAction(action)
# mark is end
self.grid_world.isEndFunc()
print("nxt state", self.grid_world.state)
print("---------------------")
self.isEnd = self.grid_world.isEnd
class Agent:
def __init__(self):
self.states = [] # record position and action taken at the position
self.actions = ["up", "down", "left", "right"]
self.grid_world = GridWorld()
self.isEnd = self.grid_world.isEnd
self.lr = 0.2
self.exp_rate = 0.3#-1#0.3#0.3#0.3
self.decay_gamma = 0.9
# initial Q values
self.Q_values = {}
for i in range(BOARD_ROWS):
for j in range(BOARD_COLS):
self.Q_values[(i, j)] = {}
for a in self.actions:
self.Q_values[(i, j)][a] = 0 # Q value is a dict of dict
self.state_values_vec = np.zeros((len(self.Q_values)))
self.policy_list = list()
def chooseAction(self):
# choose action with most expected value
mx_nxt_reward = -np.inf
action = ""
if np.random.uniform(0, 1) <= self.exp_rate:
action = np.random.choice(self.actions)
else:
# greedy action
for a in self.actions:
current_position = self.grid_world.state
nxt_reward = self.Q_values[current_position][a]
if nxt_reward >= mx_nxt_reward:
action = a
mx_nxt_reward = nxt_reward
# print("current pos: {}, greedy aciton: {}".format(self.grid_world.state, action))
return action
def takeAction(self, action):
position = self.grid_world.nxtPosition(action)
# update GridWorld
return GridWorld(state=position)
def reset(self):
self.states = []
self.grid_world = GridWorld()
self.isEnd = self.grid_world.isEnd
def play(self, rounds=10):
i = 0
histories = list()
data_sample = 0
while i < rounds:
# to the end of game back propagate reward
if self.grid_world.isEnd:
# back propagate
reward = self.grid_world.giveReward()
for a in self.actions:
self.Q_values[self.grid_world.state][a] = reward
#print("Game End Reward", reward)
next_state = (self.grid_world.state, 'right')
for s in reversed(self.states):
next_q_value = self.Q_values[next_state[0]][next_state[1]]
current_q_value = self.Q_values[s[0]][s[1]]
#reward = current_q_value + self.lr * (self.decay_gamma * reward - current_q_value)
reward = current_q_value + self.lr * (self.decay_gamma * next_q_value - current_q_value)
self.Q_values[s[0]][s[1]] = round(reward, 3)
next_state = s
self.policy_list.append(self.make_policy_table_from_q())
self.reset()
i += 1
aa = [[k for e, k in e.items()] for e in [v for k, v in self.Q_values.items()]]
ab = np.array(aa, dtype=float)
q_value_numpy = np.max(ab, axis=1, keepdims=False)
diff = np.linalg.norm(self.state_values_vec[:] - q_value_numpy[:])
self.state_values_vec = q_value_numpy
#print("iter {0}".format(i))
#print("diff {0}".format(diff))
#print("qvalue {0}".format(np.linalg.norm(q_value_numpy[:])))
print("{0}".format(data_sample))
value_scalar= np.linalg.norm(q_value_numpy[:])
histories.append((value_scalar, diff, int(data_sample)))
data_sample = 0
else:
action = self.chooseAction()
# append trace
self.states.append([(self.grid_world.state), action]) #s, a
#print("current position {} action {}".format(self.grid_world.state, action))
# by taking the action, it reaches the next state
self.grid_world = self.takeAction(action)
# mark is end
self.grid_world.isEndFunc()
#print("nxt state", self.grid_world.state)
#print("---------------------{0}".format(i))
self.isEnd = self.grid_world.isEnd
data_sample += 1
return histories, self.policy_list
def make_policy_table_from_q(self):
convert_list = list()
for k, v in self.Q_values.items():
convert_list.append(np.argmax(np.array([val for (key, val) in v.items()], float)))
return convert_list
