def feed_forward_generator()

in gala/storage.py [0:0]


    def feed_forward_generator(self,
                               advantages,
                               num_mini_batch=None,
                               mini_batch_size=None):
        num_steps, num_processes = self.rewards.size()[0:2]
        batch_size = num_processes * num_steps

        if mini_batch_size is None:
            assert batch_size >= num_mini_batch, (
                "PPO requires the number of processes ({}) "
                "* number of steps ({}) = {} "
                "to be greater than or equal to the number of PPO mini batches ({})."
                "".format(num_processes, num_steps, num_processes * num_steps,
                          num_mini_batch))
            mini_batch_size = batch_size // num_mini_batch
        sampler = BatchSampler(
            SubsetRandomSampler(range(batch_size)),
            mini_batch_size,
            drop_last=True)
        for indices in sampler:
            obs_batch = self.obs[:-1].view(-1, *self.obs.size()[2:])[indices]
            recurrent_hidden_states_batch = self.recurrent_hidden_states[:-1].view(
                -1, self.recurrent_hidden_states.size(-1))[indices]
            actions_batch = self.actions.view(-1,
                                              self.actions.size(-1))[indices]
            value_preds_batch = self.value_preds[:-1].view(-1, 1)[indices]
            return_batch = self.returns[:-1].view(-1, 1)[indices]
            masks_batch = self.masks[:-1].view(-1, 1)[indices]
            old_action_log_probs_batch = self.action_log_probs.view(-1,
                                                                    1)[indices]
            if advantages is None:
                adv_targ = None
            else:
                adv_targ = advantages.view(-1, 1)[indices]

            yield obs_batch, recurrent_hidden_states_batch, actions_batch, \
                value_preds_batch, return_batch, masks_batch, old_action_log_probs_batch, adv_targ