def test_tab_featb_functions():
env = feature_make('FrozenLake8x8-v0')
params = np.zeros(64)
params[-1] = 1.
rf = FeatureBasedRewardFunction(env, params)
domain = rf.domain()
rf2 = TabularRewardFunction(env, params)
rf_true = make_true_reward('FrozenLake8x8-v0')
rew1 = rf.reward(domain)
rew2 = rf2.reward(domain)
rew_true = rf_true.reward(domain)
assert np.all(rew_true == rew1)
assert np.all(rew1 == rew2)
assert rew_true.shape == rew1.shape
assert rew1.shape == rew2.shape
def train(self, no_irl_iterations: int,
no_rl_episodes_per_irl_iteration: int,
no_irl_episodes_per_irl_iteration: int):
"""Train algorithm. See abstract base class for parameter types."""
# calculate feature expectations
expert_feature_count = self.feature_count(self.expert_trajs, gamma=1.0)
# start with an agent
agent = self.rl_alg_factory(self.env)
reward_function = FeatureBasedRewardFunction(self.env, 'random')
self.env.update_reward_function(reward_function)
theta = reward_function.parameters
irl_iteration_counter = 0
while irl_iteration_counter < no_irl_iterations:
irl_iteration_counter += 1
if self.config['verbose']:
print('IRL ITERATION ' + str(irl_iteration_counter))
# compute policy
agent.train(no_rl_episodes_per_irl_iteration)
policy = agent.policy_array()
# compute state visitation frequencies, discard absorbing state
svf = self.expected_svf(policy)[:-1]
# compute gradients
grad = (expert_feature_count - self.feat_map.T.dot(svf))
# update params
theta += self.config['lr'] * grad
reward_function.update_parameters(theta)
evaluation_input = {
'irl_agent': agent,
'irl_reward': reward_function
}
self.evaluate_metrics(evaluation_input)
return theta
def train(self, no_irl_iterations: int,
no_rl_episodes_per_irl_iteration: int,
no_irl_episodes_per_irl_iteration: int):
"""
"""
sa_visit_count, P0 = self.sa_visitations()
# calculate feature expectations
expert_feature_count = self.feature_count(self.expert_trajs, gamma=1.0)
# initialize the parameters
reward_function = FeatureBasedRewardFunction(self.env, 'random')
theta = reward_function.parameters
agent = self.rl_alg_factory(self.env)
irl_iteration_counter = 0
while irl_iteration_counter < no_irl_iterations:
irl_iteration_counter += 1
if self.config['verbose']:
print('IRL ITERATION ' + str(irl_iteration_counter))
reward_wrapper = unwrap_env(self.env, RewardWrapper)
reward_wrapper.update_reward_parameters(theta)
# compute policy
agent.train(no_rl_episodes_per_irl_iteration)
policy = agent.policy_array()
state_values = agent.state_values
q_values = agent.q_values
# occupancy measure
d = self.occupancy_measure(policy=policy,
initial_state_dist=P0)[:-1]
# log-likeilihood gradient
grad = -(expert_feature_count - np.dot(self.feat_map.T, d))
# graduate descent
theta -= self.config['lr'] * grad
evaluation_input = {
'irl_agent': agent,
'irl_reward': reward_function
}
self.evaluate_metrics(evaluation_input)
return theta
def test_is_unwrappable_to():
assert is_unwrappable_to(make_env('FrozenLake-v0'), TimeLimit)
assert is_unwrappable_to(make_env('FrozenLake-v0'), DiscreteEnv)
assert is_unwrappable_to(feature_wrapper.make('FrozenLake-v0'),
FrozenLakeFeatureWrapper)
assert is_unwrappable_to(feature_wrapper.make('FrozenLake8x8-v0'),
FrozenLakeFeatureWrapper)
assert is_unwrappable_to(feature_wrapper.make('FrozenLake-v0'),
feature_wrapper.FeatureWrapper)
env = feature_wrapper.make('FrozenLake-v0')
reward_function = FeatureBasedRewardFunction(env, 'random')
env = RewardWrapper(env, reward_function)
assert is_unwrappable_to(env, RewardWrapper)
assert is_unwrappable_to(env, feature_wrapper.FeatureWrapper)
assert is_unwrappable_to(env, DiscreteEnv)
assert is_unwrappable_to(env, gym.Env)
def train(self,
step_size=1e-2,
time_limit=60,
n_trajs=10000,
verbose=False):
'''Train for at most time_limit seconds w/ n_trajs non-expert trajs.
Args:
step_size -- `float`, size of each gradient ascent step
time_limit -- `int`, number of seconds to train
n_trajs -- `int`, number of non-expert trajs to be collected
verbose -- `bool`, if true print gradient norms and reward weights
Returns nothing.
'''
t0 = time.time()
reward_coefficients = self.reward_function.parameters
trajs = collect_trajs(self.env, self.baseline_agent, n_trajs,
self.horizon)
# Estimate subgradient based on collected trajectories, then
# update reward coefficients.
if verbose:
print('Starting subgradient ascent...')
iteration_counter = 0
while time.time() < t0 + time_limit:
# replace the previous with the following line when using pdb
# for _ in range(50):
subgrads = self.subgradients(trajs, reward_coefficients)
reward_coefficients += step_size * subgrads
reward_coefficients /= np.linalg.norm(reward_coefficients)
iteration_counter += 1
if verbose and iteration_counter < 10:
print('ITERATION ' + str(iteration_counter) + ' grad norm: ' +
str(np.linalg.norm(subgrads)))
print('ITERATION ' + str(iteration_counter) +
' reward coefficients: ' + str(reward_coefficients))
if verbose:
print('Final reward coefficients: ' + str(reward_coefficients))
self.reward_function = FeatureBasedRewardFunction(
self.env_rew, reward_coefficients)
self.env_rew.update_reward_function(self.reward_function)
def reward_function_factory(env):
return FeatureBasedRewardFunction(env, 'random')
# a one-hot encoding of the state space as features.
env = feature_wrapper.make('FrozenLake-v0')
# Generate expert trajectories.
expert_agent = rl_alg_factory(env)
print('Training expert agent...')
expert_agent.train(15)
print('Done training expert')
expert_trajs = collect_trajs(env, expert_agent, no_episodes,
max_steps_per_episode, store_to)
# you can comment out the previous block if expert data has already
# been generated and load the trajectories from file by uncommenting
# next 2 lines:
# with open(store_to + 'trajs.pkl', 'rb') as f:
# expert_trajs = pickle.load(f)
# Provide random reward function as initial reward estimate.
# This probably isn't really required.
reward_function = FeatureBasedRewardFunction(env, np.random.normal(size=16))
env = RewardWrapper(env, reward_function)
# Run projection algorithm for up to 5 minutes.
appr_irl = ApprIRL(env, expert_trajs, rl_alg_factory, proj=True)
appr_irl.train(time_limit=600,
rl_time_per_iteration=45,
eps=0,
no_trajs=100,
max_steps_per_episode=100,
verbose=True)
def quick_run_alg(alg_class, config={}):
env = feature_wrapper.make('FrozenLake-v0')
reward_function = FeatureBasedRewardFunction(env, 'random')
env = RewardWrapper(env, reward_function)
def rl_alg_factory(env):
return ValueIteration(env, {})
expert_trajs = [{
'states': [
0, 0, 4, 0, 4, 8, 4, 4, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 4, 4, 8, 9,
8, 8, 9, 10, 14, 15
],
'actions': [
0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 1,
3, 3, 1, 0, 1
],
'rewards': [
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
1.0
],
'true_rewards': [],
'features': [
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 1., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 1.
])
]
}, {
'states': [0, 4, 8, 8, 9, 10, 6, 2, 6, 10, 14, 15],
'actions': [0, 0, 3, 3, 1, 0, 2, 0, 2, 0, 1],
'rewards': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0],
'true_rewards': [],
'features': [
np.array([
0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 1., 0., 0., 0., 0., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 1., 0.
]),
np.array([
0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 1.
])
]
}]
metrics = []
alg = alg_class(env, expert_trajs, rl_alg_factory, metrics, config)
alg.train(2, 2, 2)
def train(self,
time_limit=300,
rl_time_per_iteration=30,
eps=0,
no_trajs=1000,
max_steps_per_episode=1000,
verbose=False):
'''Accumulate feature counts and estimate reward function.
Args:
time_limit: total training time in seconds
rl_time_per_iteration: RL training time per step in seconds.
eps: terminate if distance to expert feature counts is below eps.
verbose: more verbose prints at runtime if true
Returns nothing.
'''
t0 = time.time()
if verbose:
alg_mode = 'projection' if self.proj else 'SVM'
print('Running Apprenticeship IRL in mode: ' + alg_mode)
# start with random agent:
agent = RandomAgent(self.env)
iteration_counter = 0
while time.time() < t0 + time_limit:
iteration_counter += 1
if verbose:
print('ITERATION ' + str(iteration_counter))
trajs = collect_trajs(self.env, agent,
no_episodes=no_trajs,
max_steps_per_episode=max_steps_per_episode)
if verbose:
print('Average true reward per episode: '
+ str(true_reward_per_traj(trajs)))
current_feature_count = self.feature_count(trajs)
self.feature_counts.append(current_feature_count)
self.labels.append(-1.0)
feature_counts = np.array(self.feature_counts)
labels = np.array(self.labels)
if self.proj:
# using projection version of the algorithm
if iteration_counter == 1:
feature_count_bar = feature_counts[1]
else:
line = feature_counts[-1] - feature_count_bar
feature_count_bar += np.dot(
line, feature_counts[0] - feature_count_bar) / np.dot(
line, line) * line
reward_coefficients = feature_counts[0] - feature_count_bar
distance = np.linalg.norm(reward_coefficients)
else:
# using SVM version of the algorithm ("max-margin" in
# the paper, not to be confused with max-margin planning)
w = cvx.Variable(feature_counts.shape[1])
b = cvx.Variable()
objective = cvx.Minimize(cvx.norm(w, 2))
constraints = [
cvx.multiply(labels, (feature_counts * w + b)) >= 1
]
problem = cvx.Problem(objective, constraints)
problem.solve()
if w.value is None:
print('NO MORE SVM SOLUTION!!')
return
yResult = feature_counts.dot(w.value) + b.value
supportVectorRows = np.where(np.isclose(np.abs(yResult), 1))[0]
reward_coefficients = w.value
distance = 2 / problem.value
if verbose:
print('The support vectors are from iterations number ' +
str(supportVectorRows))
if verbose:
print('Reward coefficients: ' + str(reward_coefficients))
print('Distance: ' + str(distance))
self.distances.append(distance)
self.reward_function = FeatureBasedRewardFunction(
self.env, reward_coefficients)
self.env.update_reward_function(self.reward_function)
if distance <= eps:
if verbose:
print("Feature counts matched within " + str(eps) + ".")
break
if time.time() + rl_time_per_iteration >= t0 + time_limit:
break
agent = self.rl_alg_factory(self.env)
agent.train(rl_time_per_iteration)
def train(self,
feat_map,
time_limit=300,
rl_time_per_iteration=15,
verbose=False):
"""
Maximum Entropy Inverse Reinforcement Learning (Maxent IRL)
inputs:
feat_map NxD matrix - the features for each state
P_a NxN_ACTIONSxN matrix - P_a[s0, a, s1] is the transition prob of
landing at state s1 when taking action
a at state s0
gamma float - RL discount factor
trajs a list of demonstrations
lr float - learning rate
n_iters int - number of optimization steps
returns
rewards Nx1 vector - recovered state rewards
"""
t0 = time.time()
# init parameters
theta = np.random.uniform(size=(feat_map.shape[1], ))
# calc feature expectations
feat_exp = np.zeros([feat_map.shape[1]])
for episode in self.expert_trajs:
for state in episode['states']:
feat_exp += feat_map[state]
feat_exp = feat_exp / len(self.expert_trajs)
#print(feat_exp)
agent = self.rl_alg_factory(self.env)
# training
iteration_counter = 0
while time.time() < t0 + time_limit:
iteration_counter += 1
if verbose:
print('iteration: {}'.format(iteration_counter))
reward_function_estimate = FeatureBasedRewardFunction(
self.env, theta)
self.env.update_reward_function(reward_function_estimate)
# compute policy
agent.train(time_limit=rl_time_per_iteration)
policy = agent.pi
# compute state visitation frequencies
svf = self.expected_svf(policy)
# compute gradients
grad = -(feat_exp - feat_map.T.dot(svf))
# update params
theta += self.lr * grad
# return sigmoid(normalize(rewards))
self.reward_function = reward_function_estimate
return theta
def reward_function_factory(env):
return FeatureBasedRewardFunction(env, true_rews[:-1])
def train(self, no_irl_iterations: int,
no_rl_episodes_per_irl_iteration: int,
no_irl_episodes_per_irl_iteration: int):
"""
"""
sa_visit_count, P0 = self.sa_visitations()
# mean_s_visit_count = np.sum(sa_visit_count, 1) / len(self.expert_trajs)
# calculate feature expectations
expert_feature_count = self.feature_count(self.expert_trajs, gamma=1.0)
# mean_feature_count = np.dot(self.feat_map.T, expert_feature_count )
# initialize the parameters
# theta = np.random.rand(self.feat_map.shape[1])
reward_function = FeatureBasedRewardFunction(self.env, 'random')
theta = reward_function.parameters
agent = self.rl_alg_factory(self.env)
irl_iteration_counter = 0
while irl_iteration_counter < no_irl_iterations:
irl_iteration_counter += 1
if self.config['verbose']:
print('IRL ITERATION ' + str(irl_iteration_counter))
reward_function_estimate = FeatureBasedRewardFunction(
self.env, theta)
self.env.update_reward_function(reward_function_estimate)
# compute policy
agent.train(no_rl_episodes_per_irl_iteration)
policy = agent.policy_array()
state_values = agent.state_values
q_values = agent.q_values
# Log-Likelihood
# l = np.sum(sa_visit_count * (q_values - state_values.T)) # check: broadcasting works as intended or not
# occupancy measure
d = self.occupancy_measure(policy=policy, P0=P0)[:-1]
# log-likeilihood gradient
grad = -(expert_feature_count - np.dot(self.feat_map.T, d))
# graduate descent
theta -= self.config['lr'] * grad
evaluation_input = {
'irl_agent': agent,
'irl_reward': reward_function
}
self.evaluate_metrics(evaluation_input)
return theta
from irl_benchmark.irl.algorithms.maxent.me_irl import MaxEnt
from irl_benchmark.irl.collect import collect_trajs
from irl_benchmark.irl.feature.feature_wrapper import FrozenLakeFeatureWrapper
from irl_benchmark.irl.reward.reward_function import FeatureBasedRewardFunction
from irl_benchmark.irl.reward.reward_wrapper import RewardWrapper
from irl_benchmark.rl.algorithms.value_iteration import ValueIteration
from irl_benchmark.utils.utils import get_transition_matrix
store_to = 'data/frozen/expert/'
no_episodes = 1000
max_steps_per_episode = 1000
env = gym.make('FrozenLake8x8-v0')
env = FrozenLakeFeatureWrapper(env)
initial_reward_function_estimate = FeatureBasedRewardFunction(
env=env, parameters=np.zeros(64))
env = RewardWrapper(env=env, reward_function=initial_reward_function_estimate)
# Generate expert trajectories.
expert_agent = ValueIteration(env)
print('Training expert agent...')
expert_agent.train(30)
expert_trajs = collect_trajs(env, expert_agent, no_episodes,
max_steps_per_episode, store_to)
feat_map = np.eye(64)
transition_dynamics = get_transition_matrix(env)
def rl_alg_factory(env):
def reward_function_factory(env):
return FeatureBasedRewardFunction(env, np.zeros(16))
def train(self, no_irl_iterations: int,
no_rl_episodes_per_irl_iteration: int,
no_irl_episodes_per_irl_iteration: int
) -> Tuple[BaseRewardFunction, BaseRLAlgorithm]:
"""Train the apprenticeship learning IRL algorithm.
Parameters
----------
no_irl_iterations: int
The number of iteration the algorithm should be run.
no_rl_episodes_per_irl_iteration: int
The number of episodes the RL algorithm is allowed to run in
each iteration of the IRL algorithm.
no_irl_episodes_per_irl_iteration: int
The number of episodes permitted to be run in each iteration
to update the current reward estimate (e.g. to estimate state frequencies
of the currently optimal policy).
Returns
-------
Tuple[BaseRewardFunction, BaseRLAlgorithm]
The estimated reward function and a RL agent trained for this estimate.
"""
# Initialize training with a random agent.
agent = RandomAgent(self.env)
irl_iteration_counter = 0
while irl_iteration_counter < no_irl_iterations:
irl_iteration_counter += 1
if self.config['verbose']:
print('IRL ITERATION ' + str(irl_iteration_counter))
# Estimate feature count of current agent.
trajs = collect_trajs(
self.env,
agent,
no_trajectories=no_irl_episodes_per_irl_iteration)
current_feature_count = self.feature_count(
trajs, gamma=self.config['gamma'])
# add new feature count to list of feature counts
self.feature_counts.append(current_feature_count)
# for SVM mode:
self.labels.append(-1.)
# convert to numpy array:
feature_counts = np.array(self.feature_counts)
labels = np.array(self.labels)
# update reward coefficients based on mode specified in config:
if self.config['mode'] == 'projection':
# projection mode:
if irl_iteration_counter == 1:
# initialize feature_count_bar in first iteration
# set to first non-expert feature count:
feature_count_bar = feature_counts[1]
else:
# not first iteration.
# calculate line through last feature_count_bar and
# last non-expert feature count:
line = feature_counts[-1] - feature_count_bar
# new feature_count_bar is orthogonal projection of
# expert's feature count onto the line:
feature_count_bar += np.dot(
line, feature_counts[0] - feature_count_bar) / np.dot(
line, line) * line
reward_coefficients = feature_counts[0] - feature_count_bar
# compute distance as L2 norm of reward coefficients (t^(i) in paper):
distance = np.linalg.norm(reward_coefficients, ord=2)
elif self.config['mode'] == 'svm':
# svm mode:
# create quadratic programming problem definition:
weights = cvx.Variable(feature_counts.shape[1])
bias = cvx.Variable()
objective = cvx.Minimize(cvx.norm(weights, 2))
constraints = [
cvx.multiply(labels,
(feature_counts * weights + bias)) >= 1
]
problem = cvx.Problem(objective, constraints)
# solve quadratic program:
problem.solve()
if weights.value is None:
# TODO: we need to handle empty solution better.
raise RuntimeError(
'Empty solution set for linearly separable SVM.')
if self.config['verbose']:
# print support vectors
# (which last iterations where relevant for current result?)
svm_classifications = feature_counts.dot(
weights.value) + bias.value
support_vectors = np.where(
np.isclose(np.abs(svm_classifications), 1))[0]
print('The support vectors are from iterations number ' +
str(support_vectors))
reward_coefficients = weights.value
distance = 2 / problem.value
else:
raise NotImplementedError()
if self.config['verbose']:
print('Distance: ' + str(distance))
self.distances.append(distance)
# create new reward function with current coefficient estimate
reward_function = FeatureBasedRewardFunction(
self.env, reward_coefficients)
# update reward function
assert isinstance(self.env, RewardWrapper)
self.env.update_reward_function(reward_function)
# TODO: see messages with max about order of training & deducing
# check stopping criterion:
if distance <= self.config['epsilon']:
if self.config['verbose']:
print("Feature counts matched within " +
str(self.config['epsilon']) + ".")
break
# create new RL-agent
agent = self.rl_alg_factory(self.env)
# train agent (with new reward function)
agent.train(no_rl_episodes_per_irl_iteration)
evaluation_input = {
'irl_agent': agent,
'irl_reward': reward_function
}
self.evaluate_metrics(evaluation_input)
return reward_function, agent
def __init__(self,
env,
expert_trajs,
rl_alg_factory,
baseline_agent=None,
gamma=.8,
horizon=20,
delta=.05,
eps=None):
'''Set environment, RL agent factory, expert trajectories, and parameters.
Args:
env -- wrapped environment; unwrap_env must get envs of the following
types from it: gym.Env, FeatureWrapper, RewardWrapper
expert_trajs -- `list` of expert trajectories
rl_alg_factory -- function that takes an environment
and returns an RL agent
baseline_agent -- `RLAlgorithm`, used to get non-optimal trajectories.
If None, a RandomAgent will be used.
gamma -- `float`, discount factor; note that large values won't work
well for environments like FrozenLake where discounting is the
only incentive to quickly reach the goal state
horizon -- `int`, fixed length of trajectories to be considered
delta -- confidence that feature count difference between output policy
and expert policy is less than 2 * epsilon
calc_eps -- `float` or None; if None, then epsilons will be calculated
to guarantee matching expert feature counts within epsilon
with confidence delta (via Hoeffding's inequality). But
this requires the range of feature values.
NOTE: Performance of the algorithm might depend on epsilons in a way
I don't currently understand, as the epsilons occur in the expression
used to approximate the relevant subgradient (ibid., p. 187, eq. 7).
'''
# Initialize base class and put remaining args into attributes.
super(RelEnt, self).__init__(env, expert_trajs, rl_alg_factory)
self.gamma = gamma
self.horizon = horizon
self.delta = delta
# Compute remaining attributes.
# Set gym.Env and FeatureWrapper envs as attributes.
self.env_gym = unwrap_env(self.env, gym.Env)
self.env_feat = unwrap_env(self.env, FeatureWrapper)
self.env_rew = unwrap_env(self.env, RewardWrapper)
if baseline_agent is not None:
self.baseline_agent = baseline_agent
else:
self.baseline_agent = RandomAgent(self.env_gym)
# Set expert trajs, and features.
self.n_trajs = len(self.expert_trajs)
self.n_features = self.env_feat.feature_shape()[0]
assert isinstance(self.n_features, int) # Should be dim of vector.
# Initialize random reward function.
self.reward_function = FeatureBasedRewardFunction(
self.env_rew, np.random.randn(self.n_features))
# Calculate expert feature counts.
self.expert_feature_count = self.feature_count(self.expert_trajs)
# Set tolerance epsilon (one per feature) for not matching
# expert feature counts.
self.epsilons = np.zeros(self.n_features)
if eps is not None:
self.epsilons = eps
else:
# Calculate epsilons via Hoeffding (ibid., p. 184).
max_features = self.env_feat.feature_range()[1]
min_features = self.env_feat.feature_range()[0]
self.epsilons = max_features - min_features
scale = np.sqrt(-np.log(1 - self.delta) / (2 * self.n_trajs))
scale *= (self.gamma**(self.horizon + 1) - 1) / (self.gamma - 1)
self.epsilons *= scale
def reward_function_factory(env):
params = np.zeros(64)
params[-1] = 1.
return FeatureBasedRewardFunction(env, params)
def test_value_iteration():
# gamma = 1.0
env = gym.make('FrozenLake-v0')
agent = ValueIteration(env, {'gamma': 1.0})
agent.train(10)
state_values = agent.state_values
assert isinstance(state_values, np.ndarray)
assert state_values.shape == (17, )
# argmax should be state just before frisbee
# (15 is final state, 16 is absorbing state)
assert np.argmax(state_values) == 14
assert state_values[14] > 0.93 and state_values[14] < 0.95
assert state_values[15] == 0
# gamma = 0.9
env = gym.make('FrozenLake-v0')
agent = ValueIteration(env, {'gamma': 0.9})
agent.train(10)
state_values = agent.state_values
assert isinstance(state_values, np.ndarray)
assert state_values.shape == (17, )
# argmax should be state just before frisbee
# (15 is final state, 16 is absorbing state)
assert np.argmax(state_values) == 14
assert state_values[14] > 0.63 and state_values[14] < 0.65
# holes and frisbee should have zero value:
for i in [5, 7, 11, 12, 15]:
assert state_values[i] == 0
# check some q values:
# go right in second to last state
assert np.argmax(agent.q_values[14, :]) == 1
assert np.min(agent.q_values) == 0
assert np.max(agent.q_values) <= 1
# check policy:
for i in range(16):
assert np.isclose(np.sum(agent.policy(i)), 1.)
assert np.min(agent.policy(i)) >= 0.
assert np.argmax(agent.q_values[i, :]) == np.argmax(agent.policy(i))
# check softmax policy
old_state_values = agent.state_values
old_q_values = agent.q_values
agent = ValueIteration(env, {'gamma': 0.9, 'temperature': 0.1})
agent.train(10)
assert np.all(agent.state_values <= old_state_values)
# at least initial state should now have lower value:
assert agent.state_values[0] < old_state_values[0]
assert np.all(agent.q_values <= old_q_values)
# check policy:
for i in range(16):
assert np.isclose(np.sum(agent.policy(i)), 1.)
assert np.min(agent.policy(i)) >= 0.
assert np.argmax(agent.q_values[i, :]) == np.argmax(agent.policy(i))
# ordering of probabilities should stay the same with softmax
assert np.all(
np.argsort(old_q_values[i, :]) == np.argsort(agent.policy(i)))
# test policy array:
policy_array = agent.policy_array()
assert policy_array.shape == (17, 4)
for i in range(16):
assert np.all(agent.policy(i) == policy_array[i, :])
# check if true reward isn't leaked:
env = feature_wrapper.make('FrozenLake-v0')
reward_function = FeatureBasedRewardFunction(env, np.zeros(16))
env = RewardWrapper(env, reward_function)
agent = ValueIteration(env, {})
agent.train(10)
assert np.sum(agent.state_values == 0)
from irl_benchmark.irl.algorithms.maxent.me_irl import MaxEnt
from irl_benchmark.irl.collect import collect_trajs
from irl_benchmark.irl.feature.feature_wrapper import FrozenLakeFeatureWrapper
from irl_benchmark.irl.reward.reward_function import FeatureBasedRewardFunction
from irl_benchmark.irl.reward.reward_wrapper import RewardWrapper
from irl_benchmark.metrics.inverse_learning_error import ILE
from irl_benchmark.rl.algorithms.value_iteration import ValueIteration
from irl_benchmark.utils.utils import get_transition_matrix
store_to = 'data/frozen/expert/'
no_episodes = 1000
max_steps_per_episode = 1000
env = gym.make('FrozenLake8x8-v0')
env = FrozenLakeFeatureWrapper(env)
initial_reward_function_estimate = FeatureBasedRewardFunction(
env, np.zeros(64))
env = RewardWrapper(env, initial_reward_function_estimate)
# Generate expert trajectories.
expert_agent = ValueIteration(env)
print('Training expert agent...')
expert_agent.train(10)
expert_trajs = collect_trajs(env, expert_agent, no_episodes,
max_steps_per_episode, store_to)
feat_map = np.eye(64)
transition_dynamics = get_transition_matrix(env)
def rl_alg_factory(env):
def maze_world_0(env):
parameters = np.array(
[REWARD_MOVE, REWARD_SMALL, REWARD_MEDIUM, REWARD_LARGE])
print('Create env for true reward function')
return FeatureBasedRewardFunction(env, parameters, action_in_domain=True)
def test_random_featb_function():
env = make_wrapped_env('FrozenLake-v0', with_feature_wrapper=True)
rf = FeatureBasedRewardFunction(env, 'random')
