def update(self, step, ob, ac, ret=None):
info = defaultdict(list)
config = self._config
sess = U.get_session()
global_step = sess.run(self.global_step)
sess.run(self._update_global_step)
pi = self._policy
ob_dict = self._env.get_ob_dict(ob)
if self._config.obs_norm == 'learn':
for ob_name in pi.ob_type:
pi.ob_rms[ob_name].update(ob_dict[ob_name])
with self.timed("update global network"):
for _ in range(self._config.global_iters):
# policy network
for (mb_ob, mb_ac) in dataset.iterbatches(
(ob, ac),
include_final_partial_batch=False,
batch_size=self._config.global_batch_size):
ob_list = pi.get_ob_list(mb_ob)
fetched = self._pol_loss(mb_ac, *ob_list)
loss, g = fetched['loss'], fetched['g']
self._pol_adam.update(g, self._config.global_stepsize)
info['global/loss'].append(np.mean(loss))
info['global/grad_norm'].append(np.linalg.norm(g))
if config.global_vf:
# value network
for (mb_ob, mb_ret) in dataset.iterbatches(
(ob, ret),
include_final_partial_batch=False,
batch_size=self._config.global_batch_size):
ob_list = pi.get_ob_list(mb_ob)
fetched = self._vf_loss(mb_ret, *ob_list)
vf_loss, vf_g = fetched['vf_loss'], fetched['vf_g']
self._vf_adam.update(vf_g,
self._config.global_stepsize)
info['global/vf_loss'].append(np.mean(vf_loss))
info['global/vf_grad_norm'].append(
np.linalg.norm(vf_g))
for key, value in info.items():
info[key] = np.mean(value)
info['global/global_norm'] = self._global_norm()
return info
def learn(env,
policy_func,
reward_giver,
reward_guidance,
expert_dataset,
rank,
pretrained,
pretrained_weight,
*,
g_step,
d_step,
entcoeff,
save_per_iter,
ckpt_dir,
log_dir,
timesteps_per_batch,
task_name,
gamma,
lam,
algo,
max_kl,
cg_iters,
cg_damping=1e-2,
vf_stepsize=3e-4,
d_stepsize=1e-4,
vf_iters=3,
max_timesteps=0,
max_episodes=0,
max_iters=0,
loss_percent=0.0,
callback=None):
nworkers = MPI.COMM_WORLD.Get_size()
rank = MPI.COMM_WORLD.Get_rank()
np.set_printoptions(precision=3)
# Setup losses and stuff
# ----------------------------------------
ob_space = env.observation_space
ac_space = env.action_space
policy = build_policy(env, 'mlp', value_network='copy')
ob = observation_placeholder(ob_space)
with tf.variable_scope('pi'):
pi = policy(observ_placeholder=ob)
with tf.variable_scope('oldpi'):
oldpi = policy(observ_placeholder=ob)
atarg = tf.placeholder(
dtype=tf.float32,
shape=[None]) # Target advantage function (if applicable)
ret = tf.placeholder(dtype=tf.float32, shape=[None]) # Empirical return
ac = pi.pdtype.sample_placeholder([None])
kloldnew = oldpi.pd.kl(pi.pd)
ent = pi.pd.entropy()
meankl = tf.reduce_mean(kloldnew)
meanent = tf.reduce_mean(ent)
entbonus = entcoeff * meanent
vferr = tf.reduce_mean(tf.square(pi.vf - ret))
ratio = tf.exp(pi.pd.logp(ac) -
oldpi.pd.logp(ac)) # advantage * pnew / pold
surrgain = tf.reduce_mean(ratio * atarg)
optimgain = surrgain + entbonus
losses = [optimgain, meankl, entbonus, surrgain, meanent]
loss_names = ["optimgain", "meankl", "entloss", "surrgain", "entropy"]
dist = meankl
all_var_list = get_trainable_variables('pi')
# var_list = [v for v in all_var_list if v.name.startswith("pi/pol") or v.name.startswith("pi/logstd")]
# vf_var_list = [v for v in all_var_list if v.name.startswith("pi/vff")]
var_list = get_pi_trainable_variables("pi")
vf_var_list = get_vf_trainable_variables("pi")
# assert len(var_list) == len(vf_var_list) + 1
d_adam = MpiAdam(reward_giver.get_trainable_variables())
guidance_adam = MpiAdam(reward_guidance.get_trainable_variables())
vfadam = MpiAdam(vf_var_list)
get_flat = U.GetFlat(var_list)
set_from_flat = U.SetFromFlat(var_list)
klgrads = tf.gradients(dist, var_list)
flat_tangent = tf.placeholder(dtype=tf.float32,
shape=[None],
name="flat_tan")
shapes = [var.get_shape().as_list() for var in var_list]
start = 0
tangents = []
for shape in shapes:
sz = U.intprod(shape)
tangents.append(tf.reshape(flat_tangent[start:start + sz], shape))
start += sz
gvp = tf.add_n([
tf.reduce_sum(g * tangent)
for (g, tangent) in zipsame(klgrads, tangents)
]) # pylint: disable=E1111
fvp = U.flatgrad(gvp, var_list)
assign_old_eq_new = U.function(
[], [],
updates=[
tf.assign(oldv, newv)
for (oldv,
newv) in zipsame(get_variables('oldpi'), get_variables('pi'))
])
compute_losses = U.function([ob, ac, atarg], losses)
compute_lossandgrad = U.function([ob, ac, atarg], losses +
[U.flatgrad(optimgain, var_list)])
compute_fvp = U.function([flat_tangent, ob, ac, atarg], fvp)
compute_vflossandgrad = U.function([ob, ret],
U.flatgrad(vferr, vf_var_list))
@contextmanager
def timed(msg):
if rank == 0:
print(colorize(msg, color='magenta'))
tstart = time.time()
yield
print(
colorize("done in %.3f seconds" % (time.time() - tstart),
color='magenta'))
else:
yield
def allmean(x):
assert isinstance(x, np.ndarray)
out = np.empty_like(x)
MPI.COMM_WORLD.Allreduce(x, out, op=MPI.SUM)
out /= nworkers
return out
U.initialize()
th_init = get_flat()
MPI.COMM_WORLD.Bcast(th_init, root=0)
set_from_flat(th_init)
d_adam.sync()
guidance_adam.sync()
vfadam.sync()
if rank == 0:
print("Init param sum", th_init.sum(), flush=True)
# Prepare for rollouts
# ----------------------------------------
seg_gen = traj_segment_generator(pi,
env,
reward_giver,
reward_guidance,
timesteps_per_batch,
stochastic=True,
algo=algo,
loss_percent=loss_percent)
episodes_so_far = 0
timesteps_so_far = 0
iters_so_far = 0
tstart = time.time()
lenbuffer = deque(maxlen=40) # rolling buffer for episode lengths
rewbuffer = deque(maxlen=40) # rolling buffer for episode rewards
true_rewbuffer = deque(maxlen=40)
assert sum([max_iters > 0, max_timesteps > 0, max_episodes > 0]) == 1
g_loss_stats = stats(loss_names)
d_loss_stats = stats(reward_giver.loss_name)
ep_stats = stats(["True_rewards", "Rewards", "Episode_length"])
# if provide pretrained weight
if pretrained_weight is not None:
U.load_state(pretrained_weight, var_list=pi.get_variables())
while True:
if callback: callback(locals(), globals())
if max_timesteps and timesteps_so_far >= max_timesteps:
break
elif max_episodes and episodes_so_far >= max_episodes:
break
elif max_iters and iters_so_far >= max_iters:
break
# Save model
if rank == 0 and iters_so_far % save_per_iter == 0 and ckpt_dir is not None:
fname = os.path.join(ckpt_dir, task_name)
os.makedirs(os.path.dirname(fname), exist_ok=True)
saver = tf.train.Saver()
saver.save(tf.get_default_session(), fname)
logger.log("********** Iteration %i ************" % iters_so_far)
# global flag_render
# if iters_so_far > 0 and iters_so_far % 10 ==0:
# flag_render = True
# else:
# flag_render = False
def fisher_vector_product(p):
return allmean(compute_fvp(p, *fvpargs)) + cg_damping * p
# ------------------ Update G ------------------
logger.log("Optimizing Policy...")
for _ in range(g_step):
with timed("sampling"):
seg = seg_gen.__next__()
print('rewards', seg['rew'])
add_vtarg_and_adv(seg, gamma, lam)
# ob, ac, atarg, ret, td1ret = map(np.concatenate, (obs, acs, atargs, rets, td1rets))
ob, ac, atarg, tdlamret = seg["ob"], seg["ac"], seg["adv"], seg[
"tdlamret"]
vpredbefore = seg[
"vpred"] # predicted value function before udpate
atarg = (atarg - atarg.mean()) / atarg.std(
) # standardized advantage function estimate
if hasattr(pi, "ob_rms"):
pi.ob_rms.update(ob) # update running mean/std for policy
args = seg["ob"], seg["ac"], atarg
fvpargs = [arr[::5] for arr in args]
assign_old_eq_new(
) # set old parameter values to new parameter values
with timed("computegrad"):
*lossbefore, g = compute_lossandgrad(*args)
lossbefore = allmean(np.array(lossbefore))
g = allmean(g)
if np.allclose(g, 0):
logger.log("Got zero gradient. not updating")
else:
with timed("cg"):
stepdir = cg(fisher_vector_product,
g,
cg_iters=cg_iters,
verbose=rank == 0)
assert np.isfinite(stepdir).all()
shs = .5 * stepdir.dot(fisher_vector_product(stepdir))
lm = np.sqrt(shs / max_kl)
# logger.log("lagrange multiplier:", lm, "gnorm:", np.linalg.norm(g))
fullstep = stepdir / lm
expectedimprove = g.dot(fullstep)
surrbefore = lossbefore[0]
stepsize = 1.0
thbefore = get_flat()
for _ in range(10):
thnew = thbefore + fullstep * stepsize
set_from_flat(thnew)
meanlosses = surr, kl, *_ = allmean(
np.array(compute_losses(*args)))
improve = surr - surrbefore
logger.log("Expected: %.3f Actual: %.3f" %
(expectedimprove, improve))
if not np.isfinite(meanlosses).all():
logger.log("Got non-finite value of losses -- bad!")
elif kl > max_kl * 1.5:
logger.log("violated KL constraint. shrinking step.")
elif improve < 0:
logger.log("surrogate didn't improve. shrinking step.")
else:
logger.log("Stepsize OK!")
break
stepsize *= .5
else:
logger.log("couldn't compute a good step")
set_from_flat(thbefore)
if nworkers > 1 and iters_so_far % 20 == 0:
paramsums = MPI.COMM_WORLD.allgather(
(thnew.sum(),
vfadam.getflat().sum())) # list of tuples
assert all(
np.allclose(ps, paramsums[0]) for ps in paramsums[1:])
with timed("vf"):
for _ in range(vf_iters):
for (mbob, mbret) in dataset.iterbatches(
(seg["ob"], seg["tdlamret"]),
include_final_partial_batch=False,
batch_size=128):
if hasattr(pi, "ob_rms"):
pi.ob_rms.update(
mbob) # update running mean/std for policy
g = allmean(compute_vflossandgrad(mbob, mbret))
vfadam.update(g, vf_stepsize)
g_losses = meanlosses
for (lossname, lossval) in zip(loss_names, meanlosses):
logger.record_tabular(lossname, lossval)
logger.record_tabular("ev_tdlam_before",
explained_variance(vpredbefore, tdlamret))
# ------------------ Update D ------------------
logger.log("Optimizing Discriminator...")
logger.log(fmt_row(13, reward_giver.loss_name))
ob_expert, ac_expert = expert_dataset.get_next_batch(
batch_size=len(ob))
batch_size = 128
d_losses = [
] # list of tuples, each of which gives the loss for a minibatch
with timed("Discriminator"):
for (ob_batch, ac_batch) in dataset.iterbatches(
(ob, ac),
include_final_partial_batch=False,
batch_size=batch_size):
ob_expert, ac_expert = expert_dataset.get_next_batch(
batch_size=batch_size)
# update running mean/std for reward_giver
if hasattr(reward_giver, "obs_rms"):
reward_giver.obs_rms.update(
np.concatenate((ob_batch, ob_expert), 0))
*newlosses, g = reward_giver.lossandgrad(ob_batch, ob_expert)
d_adam.update(allmean(g), d_stepsize)
d_losses.append(newlosses)
logger.log(fmt_row(13, np.mean(d_losses, axis=0)))
# ------------------ Update Guidance ------------
logger.log("Optimizing Guidance...")
logger.log(fmt_row(13, reward_guidance.loss_name))
batch_size = 128
guidance_losses = [
] # list of tuples, each of which gives the loss for a minibatch
with timed("Guidance"):
for ob_batch, ac_batch in dataset.iterbatches(
(ob, ac),
include_final_partial_batch=False,
batch_size=batch_size):
ob_expert, ac_expert = expert_dataset.get_next_batch(
batch_size=batch_size)
idx_condition = process_expert(ob_expert, ac_expert)
pick_idx = (idx_condition >= loss_percent)
# pick_idx = idx_condition
ob_expert_p = ob_expert[pick_idx]
ac_expert_p = ac_expert[pick_idx]
ac_batch_p = []
for each_ob in ob_expert_p:
tmp_ac, _, _, _ = pi.step(each_ob, stochastic=True)
ac_batch_p.append(tmp_ac)
# update running mean/std for reward_giver
if hasattr(reward_guidance, "obs_rms"):
reward_guidance.obs_rms.update(ob_expert_p)
# reward_guidance.train(expert_s=ob_batch_p, agent_a=ac_batch_p, expert_a=ac_expert_p)
*newlosses, g = reward_guidance.lossandgrad(
ob_expert_p, ac_batch_p, ac_expert_p)
guidance_adam.update(allmean(g), d_stepsize)
guidance_losses.append(newlosses)
logger.log(fmt_row(13, np.mean(guidance_losses, axis=0)))
lrlocal = (seg["ep_lens"], seg["ep_rets"], seg["ep_true_rets"]
) # local values
listoflrpairs = MPI.COMM_WORLD.allgather(lrlocal) # list of tuples
lens, rews, true_rets = map(flatten_lists, zip(*listoflrpairs))
true_rewbuffer.extend(true_rets)
lenbuffer.extend(lens)
rewbuffer.extend(rews)
logger.record_tabular("EpLenMean", np.mean(lenbuffer))
logger.record_tabular("EpRewMean", np.mean(rewbuffer))
logger.record_tabular("EpTrueRewMean", np.mean(true_rewbuffer))
logger.record_tabular("EpThisIter", len(lens))
episodes_so_far += len(lens)
timesteps_so_far += sum(lens) * g_step
iters_so_far += 1
logger.record_tabular("EpisodesSoFar", episodes_so_far)
logger.record_tabular("TimestepsSoFar", timesteps_so_far)
logger.record_tabular("TimeElapsed", time.time() - tstart)
if rank == 0:
logger.dump_tabular()
def _update_policy(self, rollouts, it):
pi = self._policy
seg = rollouts[self.id]
info = defaultdict(list)
ob, ac, atarg, tdlamret = seg["ob"], seg["ac"], seg["adv"], seg[
"tdlamret"]
atarg = (atarg - atarg.mean()) / atarg.std()
info['adv'] = np.mean(atarg)
other_ob_list = []
for i, other_pi in enumerate(self._pis):
other_ob_list.extend(other_pi.get_ob_list(rollouts[i]["ob"]))
ob_list = pi.get_ob_list(ob)
args = ob_list * self._config.num_contexts + \
other_ob_list * 2 + ob_list + [ac, atarg]
fvpargs = [arr[::5] for arr in args]
def fisher_vector_product(p):
return self._all_mean(self._compute_fvp(
p, *fvpargs)) + self._config.cg_damping * p
self._update_oldpi()
with self.timed("compute gradient"):
lossbefore = self._compute_lossandgrad(*args)
lossbefore = {
k: self._all_mean(np.array(lossbefore[k]))
for k in sorted(lossbefore.keys())
}
g = lossbefore['g']
if np.allclose(g, 0):
logger.log("Got zero gradient. not updating")
else:
with self.timed("compute conjugate gradient"):
stepdir = cg(fisher_vector_product,
g,
cg_iters=self._config.cg_iters,
verbose=False)
assert np.isfinite(stepdir).all()
shs = .5 * stepdir.dot(fisher_vector_product(stepdir))
lm = np.sqrt(shs / self._config.max_kl)
fullstep = stepdir / lm
expectedimprove = g.dot(fullstep)
surrbefore = lossbefore['pol_loss']
stepsize = 1.0
thbefore = self._get_flat()
for _ in range(10):
thnew = thbefore + fullstep * stepsize
self._set_from_flat(thnew)
meanlosses = self._compute_losses(*args)
meanlosses = {
k: self._all_mean(np.array(meanlosses[k]))
for k in sorted(meanlosses.keys())
}
for key, value in meanlosses.items():
if key != 'g':
info[key].append(value)
surr = meanlosses['pol_loss']
kl = meanlosses['kl']
meanlosses = np.array(list(meanlosses.values()))
improve = surr - surrbefore
logger.log("Expected: %.3f Actual: %.3f" %
(expectedimprove, improve))
if not np.isfinite(meanlosses).all():
logger.log("Got non-finite value of losses -- bad!")
elif kl > self._config.max_kl * 1.5:
logger.log("violated KL constraint. shrinking step.")
elif improve < 0:
logger.log("surrogate didn't improve. shrinking step.")
else:
logger.log("Stepsize OK!")
break
stepsize *= .5
else:
logger.log("couldn't compute a good step")
self._set_from_flat(thbefore)
if self._num_workers > 1 and it % 20 == 0:
paramsums = MPI.COMM_WORLD.allgather(
(thnew.sum(),
self._vf_adam.getflat().sum())) # list of tuples
assert all(
np.allclose(ps, paramsums[0])
for ps in paramsums[1:]), paramsums
with self.timed("updating value function"):
for _ in range(self._config.vf_iters):
for (mbob, mbret) in dataset.iterbatches(
(ob, tdlamret),
include_final_partial_batch=False,
batch_size=self._config.vf_batch_size):
ob_list = pi.get_ob_list(mbob)
g = self._all_mean(
self._compute_vflossandgrad(*ob_list, mbret))
self._vf_adam.update(g, self._config.vf_stepsize)
vf_loss = self._all_mean(
np.array(self._compute_vfloss(*ob_list, mbret)))
info['vf_loss'].append(vf_loss)
for key, value in info.items():
info[key] = np.mean(value)
return info
