ray/rllib/agents/pg/tests/test_pg.py

119 lines
4.2 KiB
Python

import numpy as np
import unittest
import ray
import ray.rllib.agents.pg as pg
from ray.rllib.agents.pg import PGTrainer
from ray.rllib.evaluation.postprocessing import Postprocessing
from ray.rllib.models.tf.tf_action_dist import Categorical
from ray.rllib.models.torch.torch_action_dist import TorchCategorical
from ray.rllib.policy.sample_batch import SampleBatch
from ray.rllib.utils import check, fc
class TestPG(unittest.TestCase):
def setUp(self):
ray.init()
def tearDown(self):
ray.shutdown()
def test_pg_pipeline(ray_start_regular):
trainer = PGTrainer(
env="CartPole-v0",
config={
"min_iter_time_s": 0,
"use_pipeline_impl": True
})
assert isinstance(trainer.train(), dict)
def test_pg_compilation(self):
"""Test whether a PGTrainer can be built with both frameworks."""
config = pg.DEFAULT_CONFIG.copy()
config["num_workers"] = 0 # Run locally.
# tf.
trainer = pg.PGTrainer(config=config, env="CartPole-v0")
num_iterations = 2
for i in range(num_iterations):
trainer.train()
# Torch.
config["use_pytorch"] = True
trainer = pg.PGTrainer(config=config, env="CartPole-v0")
for i in range(num_iterations):
trainer.train()
def test_pg_loss_functions(self):
"""Tests the PG loss function math."""
config = pg.DEFAULT_CONFIG.copy()
config["num_workers"] = 0 # Run locally.
config["eager"] = True
config["gamma"] = 0.99
config["model"]["fcnet_hiddens"] = [10]
config["model"]["fcnet_activation"] = "linear"
# Fake CartPole episode of n time steps.
train_batch = {
SampleBatch.CUR_OBS: np.array([[0.1, 0.2, 0.3,
0.4], [0.5, 0.6, 0.7, 0.8],
[0.9, 1.0, 1.1, 1.2]]),
SampleBatch.ACTIONS: np.array([0, 1, 1]),
SampleBatch.REWARDS: np.array([1.0, 1.0, 1.0]),
SampleBatch.DONES: np.array([False, False, True])
}
# tf.
trainer = pg.PGTrainer(config=config, env="CartPole-v0")
policy = trainer.get_policy()
vars = policy.model.trainable_variables()
# Post-process (calculate simple (non-GAE) advantages) and attach to
# train_batch dict.
# A = [0.99^2 * 1.0 + 0.99 * 1.0 + 1.0, 0.99 * 1.0 + 1.0, 1.0] =
# [2.9701, 1.99, 1.0]
train_batch = pg.post_process_advantages(policy, train_batch)
# Check Advantage values.
check(train_batch[Postprocessing.ADVANTAGES], [2.9701, 1.99, 1.0])
# Actual loss results.
results = pg.pg_tf_loss(
policy,
policy.model,
dist_class=Categorical,
train_batch=train_batch)
# Calculate expected results.
expected_logits = fc(
fc(train_batch[SampleBatch.CUR_OBS], vars[0].numpy(),
vars[1].numpy()), vars[2].numpy(), vars[3].numpy())
expected_logp = Categorical(expected_logits, policy.model).logp(
train_batch[SampleBatch.ACTIONS])
expected_loss = -np.mean(
expected_logp * train_batch[Postprocessing.ADVANTAGES])
check(results.numpy(), expected_loss, decimals=4)
# Torch.
config["use_pytorch"] = True
trainer = pg.PGTrainer(config=config, env="CartPole-v0")
policy = trainer.get_policy()
train_batch = policy._lazy_tensor_dict(train_batch)
results = pg.pg_torch_loss(
policy,
policy.model,
dist_class=TorchCategorical,
train_batch=train_batch)
expected_logits = policy.model.last_output()
expected_logp = TorchCategorical(expected_logits, policy.model).logp(
train_batch[SampleBatch.ACTIONS])
expected_loss = -np.mean(
expected_logp.detach().numpy() *
train_batch[Postprocessing.ADVANTAGES].numpy())
check(results.detach().numpy(), expected_loss, decimals=4)
if __name__ == "__main__":
import pytest
import sys
sys.exit(pytest.main(["-v", __file__]))