def ai_vs_ai(self, model_1, model_2, num_sim=50, verbose=False):
"""
Plays a game of tic tac toe between two AIs,
:param model_1: keras model of the first AI
:param model_2: keras model of the second AI
:param num_sim: the number of simulations per MCTS
:return: int, 0 if model 1 loses, 1 if it wins,
"""
# Initializing the game
game = TicTacToe()
# Initializing MCTS
mcts = MCTS()
# Getting the first player to go and the initial empty tic tac toe board state
state, player = game.reset()
if verbose:
game.print_state(state)
# If 1 human goes first else machine goes first
first_to_go = np.random.randint(2)
if first_to_go:
ai_1, ai_2 = 1, -1
else:
ai_1, ai_2 = -1, 1
while not game.is_terminal(state):
if player == ai_1:
if verbose:
print("Model 1 is currently making a choice")
for _ in range(num_sim):
mcts.search(state, game, player, model_1)
pi = mcts.best_policy(state, game, tau=0.01)
action = np.random.choice(game.action_space(), p=pi)
else:
if verbose:
print("Model 2 is currently making a choice")
for _ in range(num_sim):
mcts.search(state, game, player, model_2)
pi = mcts.best_policy(state, game, tau=0.01)
action = np.random.choice(game.action_space(), p=pi)
state, player = game.step(state, action, player)
if verbose:
game.print_state(state)
if verbose:
if game.player_win(state, ai_1):
print("ai 1 won !")
elif game.player_win(state, ai_2):
print("ai 2 won !")
else:
print("tie !")
return game.player_win(state, ai_1)
def human_vs_ai(self, pathname, num_sim=50):
"""
Plays a game of tic tac toe between an AI trained by AlphaZero and a human player
:param pathname: the path of the keras model to load and play against
:param num_sim: number of MCTS simulation
:return: None, it's just a game, have fun !
"""
# Initializing the game
game = TicTacToe()
# Initializing MCTS
mcts = MCTS()
# Loading the specified keras model
model = keras.models.load_model(pathname)
# Getting the first player to go and the initial empty tic tac toe board state
state, player = game.reset()
game.print_state(state)
# If 1 human goes first else machine goes first
first_to_go = np.random.randint(2)
if first_to_go:
human, ai = 1, -1
else:
human, ai = -1, 1
while not game.is_terminal(state):
if player == human:
print(
"Your turn to choose, select a free slot on the board (integer between 1 and 9) with no piece on it"
)
action = input()
while not action.isdigit() or int(action) < 1 or int(
action) > 9 or not game.is_valid(
state,
int(action) - 1):
print(
"Invalid input, choose an integer between 1 and 9 and make sure to target a free cell"
)
action = input()
action = int(action) - 1
else:
print(
"AI's turn, one must wonder what it's thinking right now ..."
)
for _ in range(num_sim):
mcts.search(state, game, player, model)
pi = mcts.best_policy(state, game, tau=0.01)
action = np.random.choice(game.action_space(), p=pi)
state, player = game.step(state, action, player)
game.print_state(state)
if game.player_win(state, human):
print(
"You beat AlphaZero ! Lee Sedol is very jealous right now ...")
elif game.player_win(state, ai):
print("You lost, the age of machines has now begun ...")
else:
print("Tie ! Human and machine are equal after all ... ?")
