01_1_play_frozenlake_det.py

import gym
from gym.envs.registration import register
import sys
import tty
import termios


class _Getch:

    def __call__(self):
        fd = sys.stdin.fileno()
        old_settings = termios.tcgetattr(fd)
        try:
            tty.setraw(sys.stdin.fileno())
            ch = sys.stdin.read(3)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
        return ch

inkey = _Getch()

# MACROS
LEFT = 0
DOWN = 1
RIGHT = 2
UP = 3

# Key mapping
arrow_keys = {
    '\x1b[A': UP,
    '\x1b[B': DOWN,
    '\x1b[C': RIGHT,
    '\x1b[D': LEFT}

# Register FrozenLake with is_slippery False
register(
    id='FrozenLake-v3',
    entry_point='gym.envs.toy_text:FrozenLakeEnv',
    kwargs={'map_name': '4x4', 'is_slippery': False}
)

env = gym.make('FrozenLake-v3')
env.render()  # Show the initial board

while True:
    # Choose an action from keyboard
    key = inkey()
    if key not in arrow_keys.keys():
        print("Game aborted!")
        break

    action = arrow_keys[key]
    state, reward, done, info = env.step(action)
    env.render()  # Show the board after action
    print("State: ", state, "Action: ", action,
          "Reward: ", reward, "Info: ", info)

    if done:
        print("Finished with reward", reward)
        break