| .. _distributions: | |
| Probability Distributions | |
| ========================= | |
| Probability distributions used for the different action spaces: | |
| - ``CategoricalDistribution`` -> Discrete | |
| - ``DiagGaussianDistribution`` -> Box (continuous actions) | |
| - ``StateDependentNoiseDistribution`` -> Box (continuous actions) when ``use_sde=True`` | |
| .. - ``MultiCategoricalDistribution`` -> MultiDiscrete | |
| .. - ``BernoulliDistribution`` -> MultiBinary | |
| The policy networks output parameters for the distributions (named ``flat`` in the methods). | |
| Actions are then sampled from those distributions. | |
| For instance, in the case of discrete actions. The policy network outputs probability | |
| of taking each action. The ``CategoricalDistribution`` allows to sample from it, | |
| computes the entropy, the log probability (``log_prob``) and backpropagate the gradient. | |
| In the case of continuous actions, a Gaussian distribution is used. The policy network outputs | |
| mean and (log) std of the distribution (assumed to be a ``DiagGaussianDistribution``). | |
| .. automodule:: stable_baselines3.common.distributions | |
| :members: | |