dppo/model/rl/gmm_vpg.py
2024-09-03 21:03:27 -04:00

57 lines
1.4 KiB
Python

import torch
import logging
from model.common.gmm import GMMModel
class VPG_GMM(GMMModel):
def __init__(
self,
actor,
critic,
cond_steps=1,
network_path=None,
**kwargs,
):
super().__init__(network=actor, **kwargs)
self.cond_steps = cond_steps
# Re-name network to actor
self.actor_ft = actor
# Value function for obs - simple MLP
self.critic = critic.to(self.device)
if network_path is not None:
checkpoint = torch.load(
network_path, map_location=self.device, weights_only=True
)
self.load_state_dict(
checkpoint["model"],
strict=False,
)
logging.info("Loaded actor from %s", network_path)
def get_logprobs(
self,
cond,
actions,
):
B, T, D = actions.shape
dist, entropy, std = self.forward_train(
cond.view(B, -1),
deterministic=False,
)
log_prob = dist.log_prob(actions.view(B, -1))
return log_prob, entropy, std
def loss(self, obs, chains, reward):
raise NotImplementedError
# override to diffuse over action only
@torch.no_grad()
def forward(self, cond, deterministic=False):
B = cond.shape[0]
return super().forward(
cond=cond.view(B, -1),
deterministic=deterministic,
)