Bug: Multiple actions per agent

[kosmylo]

I have identified a potential issue when trying to have multiple actions per agent.

In my example, I have 5 agents and 4 actions per agent, which means that the actions should have shape [1,5,4].

However, according to the error that I am getting, the shape of the actions is [1,1,4]. By debugging it, I found that in the function get_actions(self, state, status, exploration, actions_avail, target=False, last_hid=None) of maddpg.py the variable means had the correct shape [1, 5, 4], but then the problem was due to the following part:

if means.size(-1) > 1:
    means_ = means.sum(dim=1, keepdim=True)
    log_stds_ = log_stds.sum(dim=1, keepdim=True)
 else:
    means_ = means
    log_stds_ = log_stds

My question now is what is the purpose of this part?