[Python] UserWarning: Creating a tensor from a list of numpy.ndarrays is extremely slow. Please consider converting the list to a single numpy.ndarray with numpy.array() before converting to a tensor.

다음과 같은 에러가 발생

(py37) parkgyeongtae-2:2_cartpole-v1 pgt0409$ python 8_cartpole-v1-confirm-model.py 
8_cartpole-v1-confirm-model.py:73: UserWarning: Creating a tensor from a list of numpy.ndarrays is extremely slow. Please consider converting the list to a single numpy.ndarray with numpy.array() before converting to a tensor. (Triggered internally at  /Users/distiller/project/pytorch/torch/csrc/utils/tensor_new.cpp:210.)
  torch.FloatTensor([next_state])

 

문제의 코드는 다음과 같음

torch.FloatTensor([next_state])

 

변경

np.array(next_state, ndmin = 2)

 

해결됨