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https://github.com/saymrwulf/stable-baselines3.git
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Running PPO (not working yet)
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10 changed files with 215 additions and 157 deletions
28
tests/test_run.py
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28
tests/test_run.py
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@ -0,0 +1,28 @@
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import os
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import gym
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from torchy_baselines import TD3, CEMRL, PPO
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# def test_pendulum():
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# model = TD3('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[64, 64]), start_timesteps=100, verbose=1)
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# model.learn(total_timesteps=500, eval_freq=100)
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# model.save("test_save")
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# model.load("test_save")
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# os.remove("test_save.pth")
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#
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#
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# def test_cemrl():
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# model = CEMRL('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[16]), pop_size=2, n_grad=1,
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# start_timesteps=100, verbose=1)
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# model.learn(total_timesteps=1000, eval_freq=500)
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# model.save("test_save")
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# model.load("test_save")
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# os.remove("test_save.pth")
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def test_ppo():
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model = PPO('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[16]), verbose=1)
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model.learn(total_timesteps=1000, eval_freq=500)
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# model.save("test_save")
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# model.load("test_save")
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# os.remove("test_save.pth")
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@ -1,21 +0,0 @@
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import os
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import gym
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from torchy_baselines import TD3, CEMRL
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def test_pendulum():
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model = TD3('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[64, 64]), start_timesteps=100, verbose=1)
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model.learn(total_timesteps=500, eval_freq=100)
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model.save("test_save")
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model.load("test_save")
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os.remove("test_save.pth")
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def test_cemrl():
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model = CEMRL('MlpPolicy', 'Pendulum-v0', policy_kwargs=dict(net_arch=[16]), pop_size=2, n_grad=1,
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start_timesteps=100, verbose=1)
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model.learn(total_timesteps=1000, eval_freq=500)
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model.save("test_save")
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model.load("test_save")
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os.remove("test_save.pth")
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@ -1,4 +1,5 @@
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from torchy_baselines.td3 import TD3
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from torchy_baselines.cem_rl import CEMRL
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from torchy_baselines.ppo import PPO
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from torchy_baselines.td3 import TD3
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__version__ = "0.0.2"
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@ -4,7 +4,7 @@ import torch as th
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import torch.nn.functional as F
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import numpy as np
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from torchy_baselines import TD3
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from torchy_baselines.td3.td3 import TD3
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from torchy_baselines.common.evaluation import evaluate_policy
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from torchy_baselines.cem_rl.cem import CEM
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@ -1,3 +1,4 @@
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import torch as th
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import torch.nn as nn
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@ -1,6 +1,8 @@
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import numpy as np
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import torch as th
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from torchy_baselines.common.utils import discount_cumsum
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class ReplayBuffer(object):
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"""
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@ -43,14 +45,74 @@ class ReplayBuffer(object):
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self.full = True
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self.pos = 0
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def reset(self):
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self.pos = 0
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self.full = False
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def sample(self, batch_size):
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upper_bound = self.buffer_size if self.full else self.pos
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batch_inds = th.LongTensor(
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np.random.randint(0, upper_bound, size=batch_size))
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return self._get_samples(batch_inds)
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def _get_samples(self, batch_inds):
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return (self.states[batch_inds].to(self.device),
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self.actions[batch_inds].to(self.device),
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self.next_states[batch_inds].to(self.device),
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self.dones[batch_inds].to(self.device),
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self.rewards[batch_inds].to(self.device))
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class RolloutBuffer(ReplayBuffer):
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def __init__(self, buffer_size, state_dim, action_dim, device='cpu',
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lambda_=1, gamma=0.99):
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super(RolloutBuffer, self).__init__(buffer_size, state_dim, action_dim, device)
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self.lambda_ = lambda_
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self.gamma = gamma
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# TODO: add n_envs
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self.returns = th.zeros(self.buffer_size, 1)
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self.values = th.zeros(self.buffer_size, 1)
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self.log_probs = th.zeros(self.buffer_size, 1)
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self.advantages = th.zeros(self.buffer_size, 1)
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self.path_start_idx = 0
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def finish_path(self, last_value=0):
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"""
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From https://github.com/openai/spinningup/blob/master/spinup/algos/ppo/ppo.py
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"""
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if self.full:
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self.pos = self.buffer_size
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path_slice = slice(self.path_start_idx, self.pos)
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rewards = np.append(self.rewards[path_slice].detach().cpu().numpy(), last_value)
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values = np.append(self.values[path_slice].detach().cpu().numpy(), last_value)
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# the next two lines implement GAE-Lambda advantage calculation
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deltas = rewards[:-1] + self.gamma * values[1:] - values[:-1]
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self.advantages[path_slice, 0] = th.FloatTensor(discount_cumsum(deltas, self.gamma * self.lambda_).copy())
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# the next line computes rewards-to-go, to be targets for the value function
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self.returns[path_slice, 0] = th.FloatTensor(discount_cumsum(rewards, self.gamma)[:-1].copy())
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self.path_start_idx = self.pos
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def add(self, state, next_state, action, reward, done, value, log_prob):
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self.values[self.pos] = th.FloatTensor([value])
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self.log_probs[self.pos] = th.FloatTensor([log_prob])
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super(RolloutBuffer, self).add(state, next_state, action, reward, done)
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def reset(self):
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self.path_start_idx = 0
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super(RolloutBuffer, self).reset()
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def _get_samples(self, batch_inds):
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return (self.states[batch_inds].to(self.device),
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self.actions[batch_inds].to(self.device),
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self.next_states[batch_inds].to(self.device),
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self.dones[batch_inds].to(self.device),
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self.rewards[batch_inds].to(self.device),
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self.values[batch_inds].to(self.device),
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self.log_probs[batch_inds].to(self.device),
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self.advantages[batch_inds].to(self.device),
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self.returns[batch_inds].to(self.device))
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@ -1,5 +1,6 @@
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import random
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import scipy.signal
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import torch as th
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import numpy as np
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@ -18,3 +19,36 @@ def set_random_seed(seed, using_cuda=False):
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# Make CuDNN Determinist
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th.backends.cudnn.deterministic = True
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th.cuda.manual_seed(seed)
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# From stable_baselines.common.math_util
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# def discount(vector, gamma):
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# """
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# computes discounted sums along 0th dimension of vector x.
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# y[t] = x[t] + gamma*x[t+1] + gamma^2*x[t+2] + ... + gamma^k x[t+k],
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# where k = len(x) - t - 1
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#
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# :param vector: (np.ndarray) the input vector
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# :param gamma: (float) the discount value
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# :return: (np.ndarray) the output vector
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# """
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# assert vector.ndim >= 1
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# return scipy.signal.lfilter([1], [1, -gamma], vector[::-1], axis=0)[::-1]
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def discount_cumsum(x, discount):
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"""
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magic from rllab for computing discounted cumulative sums of vectors.
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input:
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vector x,
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[x0,
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x1,
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x2]
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output:
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[x0 + discount * x1 + discount^2 * x2,
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x1 + discount * x2,
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x2]
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"""
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return scipy.signal.lfilter([1], [1, float(-discount)], x[::-1], axis=0)[::-1]
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@ -0,0 +1 @@
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from torchy_baselines.ppo.ppo import PPO
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@ -2,52 +2,7 @@ import torch as th
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import torch.nn as nn
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from torch.distributions import Normal
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from torchy_baselines.common.policies import BasePolicy, register_policy, create_mlp, BaseNetwork
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class Actor(BaseNetwork):
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def __init__(self, state_dim, action_dim, net_arch=None, activation_fn=nn.ReLU):
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super(Actor, self).__init__()
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if net_arch is None:
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net_arch = [64, 64]
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# TODO: orthogonal initialization?
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actor_net = create_mlp(state_dim, action_dim, net_arch, activation_fn, squash_out=True)
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self.actor_net = nn.Sequential(*actor_net)
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def forward(self, x):
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return self.actor_net(x)
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class Critic(BaseNetwork):
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def __init__(self, state_dim, action_dim,
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net_arch=None, activation_fn=nn.ReLU):
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super(Critic, self).__init__()
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if net_arch is None:
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net_arch = [400, 300]
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# TODO: solve pytorch parameter registration
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# for _ in range(n_critics):
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# q_net = create_mlp(state_dim + action_dim, 1, net_arch, activation_fn)
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# self.q_net = nn.Sequential(*q_net)
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# self.q_networks.append(self.q_net)
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q1_net = create_mlp(state_dim + action_dim, 1, net_arch, activation_fn)
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self.q1_net = nn.Sequential(*q1_net)
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q2_net = create_mlp(state_dim + action_dim, 1, net_arch, activation_fn)
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self.q2_net = nn.Sequential(*q2_net)
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self.q_networks = [self.q1_net, self.q2_net]
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def forward(self, obs, action):
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qvalue_input = th.cat([obs, action], dim=1)
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return [q_net(qvalue_input) for q_net in self.q_networks]
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def q1_forward(self, obs, action):
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return self.q_networks[0](th.cat([obs, action], dim=1))
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from torchy_baselines.common.policies import BasePolicy, register_policy, create_mlp
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class PPOPolicy(BasePolicy):
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@ -71,7 +26,7 @@ class PPOPolicy(BasePolicy):
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self._build(learning_rate)
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def _build(self, learning_rate):
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shared_net = create_mlp(self.state_dim, output_dim=-1, self.net_arch, self.activation_fn)
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shared_net = create_mlp(self.state_dim, output_dim=-1, net_arch=self.net_arch, activation_fn=self.activation_fn)
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self.shared_net = nn.Sequential(*shared_net).to(self.device)
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self.actor_net = nn.Linear(self.net_arch[-1], self.action_dim)
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self.value_net = nn.Linear(self.net_arch[-1], 1)
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@ -79,18 +34,19 @@ class PPOPolicy(BasePolicy):
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self.optimizer = th.optim.Adam(self.parameters(), lr=learning_rate)
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def forward(self, state):
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state = th.FloatTensor(state).to(self.device)
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latent = self.shared_net(state)
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# TODO: initialize pi_mean weights properly
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mean_actions = self.actor_net(latent)
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action_distribution = Normal(mean_actions, self.log_std)
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# Sample from the gaussian
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action = action_distribution.rsample()
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log_prob = action_distribution.log_prob()
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log_prob = action_distribution.log_prob(action)
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# entropy = action_distribution.entropy()
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value = self.value_net(latent)
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return action, value, log_prob
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def actor_forward(self):
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def actor_forward(self, state):
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latent = self.shared_net(state)
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# TODO: initialize pi_mean weights properly
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mean_actions = self.actor_net(latent)
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@ -98,7 +54,7 @@ class PPOPolicy(BasePolicy):
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# Sample from the gaussian
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action = action_distribution.rsample()
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return action
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def value_forward(self):
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pass
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@ -5,10 +5,9 @@ import torch.nn.functional as F
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import numpy as np
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from torchy_baselines.common.base_class import BaseRLModel
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from torchy_baselines.common.utils import set_random_seed
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from torchy_baselines.common.evaluation import evaluate_policy
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from torchy_baselines.ppo.policies import ActorCriticPolicy
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from torchy_baselines.common.replay_buffer import ReplayBuffer
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from torchy_baselines.ppo.policies import PPOPolicy
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from torchy_baselines.common.replay_buffer import RolloutBuffer
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class PPO(BaseRLModel):
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@ -16,15 +15,18 @@ class PPO(BaseRLModel):
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Implementation of Proximal Policy Optimization (PPO) (clip version)
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Paper: https://arxiv.org/abs/1707.06347
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Code: https://github.com/openai/spinningup/
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and https://github.com/ikostrikov/pytorch-a2c-ppo-acktr-gail
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and stable_baselines
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"""
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def __init__(self, policy, env, policy_kwargs=None, verbose=0,
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learning_rate=1e-3, seed=0, device='auto',
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n_optim=5, batch_size=100, n_steps=256,
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gamma=0.99, lambda_=0.95,
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_init_setup_model=True):
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n_optim=5, batch_size=64, n_steps=256,
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gamma=0.99, lambda_=0.95, clip_range=0.2,
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ent_coef=0.01, vf_coef=0.5,
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_init_setup_model=True):
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super(PPO, self).__init__(policy, env, ActorCriticPolicy, policy_kwargs, verbose, device)
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super(PPO, self).__init__(policy, env, PPOPolicy, policy_kwargs, verbose, device)
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self.max_action = np.abs(self.action_space.high)
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self.learning_rate = learning_rate
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@ -34,7 +36,10 @@ class PPO(BaseRLModel):
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self.n_steps = n_steps
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self.gamma = gamma
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self.lambda_ = lambda_
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self.buffer_rollouts = None
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self.clip_range = clip_range
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self.ent_coef = ent_coef
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self.vf_coef = vf_coef
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self.rollout_buffer = None
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if _init_setup_model:
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self._setup_model()
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@ -43,10 +48,11 @@ class PPO(BaseRLModel):
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state_dim, action_dim = self.observation_space.shape[0], self.action_space.shape[0]
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self.seed(self._seed)
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self.rollout_buffer = RolloutBuffer(self.n_steps, state_dim, action_dim, self.device,
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gamma=self.gamma, lambda_=self.lambda_)
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self.policy = self.policy(self.observation_space, self.action_space,
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self.learning_rate, device=self.device, **self.policy_kwargs)
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def select_action(self, observation):
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# Normally not needed
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observation = np.array(observation)
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@ -66,52 +72,80 @@ class PPO(BaseRLModel):
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"""
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return np.clip(self.select_action(observation), -self.max_action, self.max_action)
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def collect_rollouts(self, env, rollout_buffer, n_rollout_steps=256, callback=None,
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obs=None):
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def train_actor(self, n_iterations=1, batch_size=100, tau_actor=0.005, tau_critic=0.005, replay_data=None):
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n_steps = 0
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done = obs is None
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rollout_buffer.reset()
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while n_steps < n_rollout_steps:
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# Reset environment
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if done:
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obs = env.reset()
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# No grad ok?
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with th.no_grad():
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action, value, log_prob = self.policy.forward(obs)
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action = action[0].detach().cpu().numpy()
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# Rescale and perform action
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new_obs, reward, done, _ = env.step(np.clip(action, -self.max_action, self.max_action))
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n_steps += 1
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rollout_buffer.add(obs, new_obs, action, reward, float(done), value, log_prob)
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obs = new_obs
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if done:
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value = 0.0
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obs = None
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rollout_buffer.finish_path(last_value=value)
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return obs
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def train(self, n_iterations, batch_size=64):
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# TODO: replace with iterator?
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for it in range(n_iterations):
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# Sample replay buffer
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if replay_data is None:
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state, action, next_state, done, reward = self.replay_buffer.sample(batch_size)
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else:
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state, action, next_state, done, reward = replay_data
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replay_data = self.rollout_buffer.sample(batch_size)
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state, action, next_state, done, reward, _, old_log_prob, advantage, return_batch = replay_data
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# Compute actor loss
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actor_loss = -self.critic.q1_forward(state, self.actor(state)).mean()
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_, value, log_prob = self.policy.forward(state)
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# Optimize the actor
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self.actor.optimizer.zero_grad()
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actor_loss.backward()
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self.actor.optimizer.step()
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# Normalize advantage
|
||||
# advs = returns - values
|
||||
advantage = (advantage - advantage.mean()) / (advantage.std() + 1e-8)
|
||||
|
||||
# Update the frozen target models
|
||||
if tau_critic > 0:
|
||||
for param, target_param in zip(self.critic.parameters(), self.critic_target.parameters()):
|
||||
target_param.data.copy_(tau_critic * param.data + (1 - tau_critic) * target_param.data)
|
||||
|
||||
for param, target_param in zip(self.actor.parameters(), self.actor_target.parameters()):
|
||||
target_param.data.copy_(tau_actor * param.data + (1 - tau_actor) * target_param.data)
|
||||
|
||||
def train(self, n_iterations, batch_size=100, discount=0.99,
|
||||
tau=0.005, policy_noise=0.2, noise_clip=0.5, policy_freq=2):
|
||||
|
||||
for it in range(n_iterations):
|
||||
|
||||
# Sample replay buffer
|
||||
replay_data = self.replay_buffer.sample(batch_size)
|
||||
self.train_critic(replay_data=replay_data)
|
||||
|
||||
# Delayed policy updates
|
||||
if it % policy_freq == 0:
|
||||
self.train_actor(replay_data=replay_data)
|
||||
ratio = th.exp(log_prob - old_log_prob)
|
||||
policy_loss_1 = -advantage * ratio
|
||||
policy_loss_2 = -advantage * th.clamp(ratio, 1 - self.clip_range, 1 + self.clip_range)
|
||||
policy_loss = -th.min(policy_loss_1, policy_loss_2).mean()
|
||||
# value_loss = th.mean((returns - value)**2)
|
||||
value_loss = F.mse_loss(return_batch, value)
|
||||
# Approximate entropy
|
||||
# TODO: replace by distribution entropy
|
||||
entropy_loss = th.mean(-log_prob)
|
||||
loss = policy_loss + self.ent_coef * entropy_loss + self.vf_coef * value_loss
|
||||
# TODO: check kl div
|
||||
# approx_kl_div = th.mean(old_log_prob - log_prob)
|
||||
# Optimization step
|
||||
self.policy.optimizer.zero_grad()
|
||||
loss.backward()
|
||||
# TODO: clip grad norm?
|
||||
# nn.utils.clip_grad_norm_(self.policy.parameters(), self.max_grad_norm)
|
||||
self.policy.optimizer.step()
|
||||
|
||||
def learn(self, total_timesteps, callback=None, log_interval=100,
|
||||
eval_freq=-1, n_eval_episodes=5, tb_log_name="TD3", reset_num_timesteps=True):
|
||||
eval_freq=-1, n_eval_episodes=5, tb_log_name="PPO", reset_num_timesteps=True):
|
||||
|
||||
timesteps_since_eval = 0
|
||||
episode_num = 0
|
||||
evaluations = []
|
||||
start_time = time.time()
|
||||
obs = None
|
||||
|
||||
while self.num_timesteps < total_timesteps:
|
||||
|
||||
|
|
@ -120,21 +154,13 @@ class PPO(BaseRLModel):
|
|||
if callback(locals(), globals()) is False:
|
||||
break
|
||||
|
||||
episode_reward, episode_timesteps = self.collect_rollouts(self.env, n_episodes=1,
|
||||
action_noise_std=self.action_noise_std,
|
||||
deterministic=False, callback=None,
|
||||
start_timesteps=self.start_timesteps,
|
||||
num_timesteps=self.num_timesteps,
|
||||
replay_buffer=self.buffer_rollouts)
|
||||
obs = self.collect_rollouts(self.env, self.rollout_buffer, n_rollout_steps=self.n_steps,
|
||||
obs=obs)
|
||||
episode_num += 1
|
||||
self.num_timesteps += episode_timesteps
|
||||
timesteps_since_eval += episode_timesteps
|
||||
self.num_timesteps += self.n_steps
|
||||
timesteps_since_eval += self.n_steps
|
||||
|
||||
if self.num_timesteps > 0:
|
||||
if self.verbose > 1:
|
||||
print("Total T: {} Episode Num: {} Episode T: {} Reward: {}".format(
|
||||
self.num_timesteps, episode_num, episode_timesteps, episode_reward))
|
||||
self.train(episode_timesteps, batch_size=self.batch_size, policy_freq=self.policy_freq)
|
||||
self.train(self.n_optim, batch_size=self.batch_size)
|
||||
|
||||
# Evaluate episode
|
||||
if 0 < eval_freq <= timesteps_since_eval:
|
||||
|
|
@ -158,33 +184,3 @@ class PPO(BaseRLModel):
|
|||
if env is not None:
|
||||
pass
|
||||
self.policy.load_state_dict(th.load(path))
|
||||
|
||||
|
||||
class PPOBuffer(ReplayBuffer):
|
||||
"""docstring for PPOBuffer."""
|
||||
|
||||
def __init__(self, buffer_size, state_dim, action_dim, device='cpu',
|
||||
lambda=0.95):
|
||||
super(PPOBuffer, self).__init__(buffer_size, state_dim, action_dim, device)
|
||||
|
||||
self.returns = th.zeros(self.buffer_size, 1)
|
||||
self.values = th.zeros(self.buffer_size, 1)
|
||||
self.log_probs = th.zeros(self.buffer_size, 1)
|
||||
self.advantages = th.zeros(self.buffer_size, 1)
|
||||
|
||||
def compute_gae(self):
|
||||
"""
|
||||
From https://github.com/openai/spinningup/blob/master/spinup/algos/ppo/ppo.py
|
||||
"""
|
||||
path_slice = slice(self.path_start_idx, self.pos)
|
||||
rews = np.append(self.rewards[path_slice], last_val)
|
||||
vals = np.append(self.val_buf[path_slice], last_val)
|
||||
|
||||
# the next two lines implement GAE-Lambda advantage calculation
|
||||
deltas = rews[:-1] + self.gamma * vals[1:] - vals[:-1]
|
||||
self.advantages[path_slice] = core.discount_cumsum(deltas, self.gamma * self.lam)
|
||||
|
||||
# the next line computes rewards-to-go, to be targets for the value function
|
||||
self.ret_buf[path_slice] = core.discount_cumsum(rews, self.gamma)[:-1]
|
||||
|
||||
self.path_start_idx = self.pos
|
||||
|
|
|
|||
Loading…
Reference in a new issue