How to check the Q(s,a) value from a trained DQN agent?

I have trained a DQN agent using the new Reinforcement Learning toolbox. And I wonder if it's possible to check the Q value of a certain (s,a) pair?

Answer 1

[Kajal Bansala]

Hello Yichen,

You can extract the 'rlQValueRepresentation' critic from the 'rlDQNAgent' using 'getCritic()'. From there you can use 'getValue()' to get the value for the observation. Here are my documentation page references:

getCritic: https://www.mathworks.com/help/reinforcement-learning/ref/rl.agent.rlqagent.getcritic.html

getValue: https://www.mathworks.com/help/reinforcement-learning/ref/getvalue.html

rlQValueRepresentation: https://www.mathworks.com/help/reinforcement-learning/ref/rlqvaluerepresentation.html

rlDQNAgent: https://www.mathworks.com/help/reinforcement-learning/ref/rldqnagent.html