Step function in BasicGridWorld Environment

Hello all,

I am working on writing a custom step function for my reinforcement learning environment in MATLAB and I wanted to access the step function.m file written for the BasicGridWorld in MATLAB?

Could anyone tell me how can I access it?

Thanks,

Ankita

[Ankita Tondwalkar]

I think the path to it is root/usr/local/MATLAB/MATLABversion/toolbox/rl/rl/+rl/+env/GridWorld.m

But I cannot find the step function in the GridWorld.m

[Ankita Tondwalkar]

The link below explains in detail.

https://www.mathworks.com/help/reinforcement-learning/ug/create-custom-matlab-environment-from-template.html

Thanks,

Ankita

Answer 1

[Simar]

Hi Ankita,

I understand that you want to access the “step function.m” file written for the BasicGridWorld in MATLAB.

While going through the path, there is no specific step function file provided for the BasicGridWorld environment in the Reinforcement Learning Toolbox.

If you are working on creating a custom reinforcement learning environment and want to implement a step function, you will need to define it yourself based on the specific dynamics and rules of your environment. Here is an example skeleton of how created custom class environment would be like-

classdef CustomEnvironment < rl.env.MATLABEnvironment 
properties 
% Define your environment properties here 
end 
methods 
function this = CustomEnvironment() 
% Initialize your environment here 
end 
function observation = reset(this) 
% Reset the environment to its initial state 
% Return the initial observation 
end 
function [nextObservation, reward, isDone] = step(this, action) 
% Update the environment state based on the action 
% Return the next observation, reward, and termination information 
end 
end 
end 

The step function typically takes an action as input and updates the state of the environment and accordingly returning the next state, reward, and termination information. It might be helpful to refer to the documentation below and examples provided with Reinforcement Learning Toolbox –

• https://in.mathworks.com/help/releases/R2020b/reinforcement-learning/ug/create-custom-grid-world-environments.html?searchHighlight=Basic%20Grid%20World%20Environment&s_tid=doc_srchtitle
• https://in.mathworks.com/help/releases/R2020b/reinforcement-learning/ug/train-q-learning-agent-to-solve-basic-grid-world.html
• https://in.mathworks.com/products/reinforcement-learning.html

Hope it helps!