Tianshou/examples/dqn_example.py

82 lines
2.6 KiB
Python

#!/usr/bin/env python
from __future__ import absolute_import
import tensorflow as tf
import gym
import numpy as np
import time
# our lib imports here! It's ok to append path in examples
import sys
sys.path.append('..')
from tianshou.core import losses
from tianshou.data.batch import Batch
import tianshou.data.advantage_estimation as advantage_estimation
import tianshou.core.policy.dqn as policy # TODO: fix imports as zhusuan so that only need to import to policy
import tianshou.core.value_function.action_value as value_function
# TODO: why this solves cartpole even without training?
if __name__ == '__main__':
env = gym.make('CartPole-v0')
observation_dim = env.observation_space.shape
action_dim = env.action_space.n
clip_param = 0.2
num_batches = 10
batch_size = 512
seed = 0
np.random.seed(seed)
tf.set_random_seed(seed)
### 1. build network with pure tf
observation_ph = tf.placeholder(tf.float32, shape=(None,) + observation_dim)
def my_network():
net = tf.layers.dense(observation_ph, 32, activation=tf.nn.tanh)
net = tf.layers.dense(net, 32, activation=tf.nn.tanh)
action_values = tf.layers.dense(net, action_dim, activation=None)
return None, action_values # no policy head
### 2. build policy, loss, optimizer
dqn = value_function.DQN(my_network, observation_placeholder=observation_ph, weight_update=100)
pi = policy.DQN(dqn)
dqn_loss = losses.qlearning(dqn)
total_loss = dqn_loss
optimizer = tf.train.AdamOptimizer(1e-4)
train_op = optimizer.minimize(total_loss, var_list=dqn.trainable_variables)
### 3. define data collection
data_collector = Batch(env, pi, [advantage_estimation.nstep_q_return(1, dqn)], [dqn])
### 4. start training
config = tf.ConfigProto()
config.gpu_options.allow_growth = True
with tf.Session(config=config) as sess:
sess.run(tf.global_variables_initializer())
# assign actor to pi_old
pi.sync_weights() # TODO: automate this for policies with target network
start_time = time.time()
for i in range(100):
# collect data
data_collector.collect(num_episodes=50)
# print current return
print('Epoch {}:'.format(i))
data_collector.statistics()
# update network
for _ in range(num_batches):
feed_dict = data_collector.next_batch(batch_size)
sess.run(train_op, feed_dict=feed_dict)
print('Elapsed time: {:.1f} min'.format((time.time() - start_time) / 60))