Implementation of four windy gridworlds environments (Windy Gridworld, Stochastic Windy Gridworld, Windy Gridworld with King's Moves, Stochastic Windy Gridworld with King's Moves) from book Reinforcement Learning: An Introduction compatible with OpenAI gym.
Install OpenAI gym.
Clone this repo:
$ git clone https://github.com/ibrahim-elshar/gym-windy-gridworlds.git
Then install this package via
$ pip install -e .
$ import gym
$ import gym_windy_gridworlds
$ env = gym.make('WindyGridWorld-v0')
Windy Gridworld is as descibed in example 6.5 on page 130, in the book. Windy Gridworld is a standard gridworld with start and goal states. The difference is that there is a crosswind running upward through the middle of the grid. Actions are the standard four: up, right, down, and left. In the middle region the resultant next states are shifted upward by the "wind" which strength varies from column to column. The reward is -1 until goal state is reached.
Stochastic Windy Gridworld is as described above. However, the effect of the wind "if there is any" is stochastic, sometimes varying by 1 from the value given for each column. By default, the probabilities are set uniformly such that a third of the time you move one cell according to the wind values as above, but also a third of the time you move one cell above that, and another third of the time you move one cell below that.
Windy Gridworld with King's moves is the same as Windy Gridworld, however the agent can move now in 8 possible directions including diagonal moves.
Stochastic Windy Gridworld with King's moves is an evironment where the agent can move in 8 directions including diagonal moves and the wind is stochastic as descibed in Stochastic Windy Gridworld.