I tried the code in open AI gym documentation. It works but errors occur after I close the window. The code I used is below:
import gym
env = gym.make('CartPole-v0')
for i_episode in range(20):
observation = env.reset()
for t in range(100):
env.render()
print(observation)
action = env.action_space.sample()
observation, reward, done, info = env.step(action)
if done:
print("Episode finished after {} timesteps".format(t+1))
break
And here is the error:
File "<ipython-input-3-b38d53bb166b>", line 1, in <module>
runfile('D:/Python/openAIGym.py', wdir='D:/Python')
File "D:\Anaconda\envs\tensorflow\lib\site-packages\spyder\utils\site\sitecustomize.py", line 705, in runfile
execfile(filename, namespace)
File "D:\Anaconda\envs\tensorflow\lib\site-packages\spyder\utils\site\sitecustomize.py", line 102, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)
File "D:/Python/openAIGym.py", line 6, in <module>
env.render()
File "D:\Anaconda\envs\tensorflow\lib\site-packages\gym\core.py", line 150, in render
return self._render(mode=mode, close=close)
File "D:\Anaconda\envs\tensorflow\lib\site-packages\gym\core.py", line 286, in _render
return self.env.render(mode, close)
File "D:\Anaconda\envs\tensorflow\lib\site-packages\gym\core.py", line 150, in render
return self._render(mode=mode, close=close)
File "D:\Anaconda\envs\tensorflow\lib\site-packages\gym\envs\classic_control\cartpole.py", line 146, in _render
return self.viewer.render(return_rgb_array = mode=='rgb_array')
File "D:\Anaconda\envs\tensorflow\lib\site-packages\gym\envs\classic_control\rendering.py", line 104, in render
self.window.flip()
File "D:\Anaconda\envs\tensorflow\lib\site-packages\pyglet\window\win32\__init__.py", line 311, in flip
self.context.flip()
AttributeError: 'NoneType' object has no attribute 'flip'
BTW, this is in python 3.6.
