#-*- coding: utf-8 -*- import math import numpy as np import paddle.fluid as fluid from paddle.fluid.param_attr import ParamAttr from tqdm import tqdm class DoubleDQNModel(object): def __init__(self, state_dim, action_dim, gamma, hist_len, use_cuda=False): self.img_height = state_dim[0] self.img_width = state_dim[1] self.action_dim = action_dim self.gamma = gamma self.exploration = 1.1 self.update_target_steps = 10000 // 4 self.hist_len = hist_len self.use_cuda = use_cuda self.global_step = 0 self._build_net() def _get_inputs(self): return fluid.layers.data( name='state', shape=[self.hist_len, self.img_height, self.img_width], dtype='float32'), \ fluid.layers.data( name='action', shape=[1], dtype='int32'), \ fluid.layers.data( name='reward', shape=[], dtype='float32'), \ fluid.layers.data( name='next_s', shape=[self.hist_len, self.img_height, self.img_width], dtype='float32'), \ fluid.layers.data( name='isOver', shape=[], dtype='bool') def _build_net(self): self.predict_program = fluid.Program() self.train_program = fluid.Program() self._sync_program = fluid.Program() with fluid.program_guard(self.predict_program): state, action, reward, next_s, isOver = self._get_inputs() self.pred_value = self.get_DQN_prediction(state) with fluid.program_guard(self.train_program): state, action, reward, next_s, isOver = self._get_inputs() pred_value = self.get_DQN_prediction(state) reward = fluid.layers.clip(reward, min=-1.0, max=1.0) action_onehot = fluid.layers.one_hot(action, self.action_dim) action_onehot = fluid.layers.cast(action_onehot, dtype='float32') pred_action_value = fluid.layers.reduce_sum( fluid.layers.elementwise_mul(action_onehot, pred_value), dim=1) targetQ_predict_value = self.get_DQN_prediction(next_s, target=True) next_s_predcit_value = self.get_DQN_prediction(next_s) greedy_action = fluid.layers.argmax(next_s_predcit_value, axis=1) greedy_action = fluid.layers.unsqueeze(greedy_action, axes=[1]) predict_onehot = fluid.layers.one_hot(greedy_action, self.action_dim) best_v = fluid.layers.reduce_sum( fluid.layers.elementwise_mul(predict_onehot, targetQ_predict_value), dim=1) best_v.stop_gradient = True target = reward + (1.0 - fluid.layers.cast( isOver, dtype='float32')) * self.gamma * best_v cost = fluid.layers.square_error_cost(pred_action_value, target) cost = fluid.layers.reduce_mean(cost) optimizer = fluid.optimizer.Adam(1e-3 * 0.5, epsilon=1e-3) optimizer.minimize(cost) vars = list(self.train_program.list_vars()) target_vars = list( filter(lambda x: 'GRAD' not in x.name and 'target' in x.name, vars)) policy_vars_name = [ x.name.replace('target', 'policy') for x in target_vars ] policy_vars = list(filter(lambda x: x.name in policy_vars_name, vars)) policy_vars.sort(key=lambda x: x.name) target_vars.sort(key=lambda x: x.name) with fluid.program_guard(self._sync_program): sync_ops = [] for i, var in enumerate(policy_vars): sync_op = fluid.layers.assign(policy_vars[i], target_vars[i]) sync_ops.append(sync_op) # fluid exe place = fluid.CUDAPlace(0) if self.use_cuda else fluid.CPUPlace() self.exe = fluid.Executor(place) self.exe.run(fluid.default_startup_program()) def get_DQN_prediction(self, image, target=False): image = image / 255.0 variable_field = 'target' if target else 'policy' conv1 = fluid.layers.conv2d( input=image, num_filters=32, filter_size=5, stride=1, padding=2, act='relu', param_attr=ParamAttr(name='{}_conv1'.format(variable_field)), bias_attr=ParamAttr(name='{}_conv1_b'.format(variable_field))) max_pool1 = fluid.layers.pool2d( input=conv1, pool_size=2, pool_stride=2, pool_type='max') conv2 = fluid.layers.conv2d( input=max_pool1, num_filters=32, filter_size=5, stride=1, padding=2, act='relu', param_attr=ParamAttr(name='{}_conv2'.format(variable_field)), bias_attr=ParamAttr(name='{}_conv2_b'.format(variable_field))) max_pool2 = fluid.layers.pool2d( input=conv2, pool_size=2, pool_stride=2, pool_type='max') conv3 = fluid.layers.conv2d( input=max_pool2, num_filters=64, filter_size=4, stride=1, padding=1, act='relu', param_attr=ParamAttr(name='{}_conv3'.format(variable_field)), bias_attr=ParamAttr(name='{}_conv3_b'.format(variable_field))) max_pool3 = fluid.layers.pool2d( input=conv3, pool_size=2, pool_stride=2, pool_type='max') conv4 = fluid.layers.conv2d( input=max_pool3, num_filters=64, filter_size=3, stride=1, padding=1, act='relu', param_attr=ParamAttr(name='{}_conv4'.format(variable_field)), bias_attr=ParamAttr(name='{}_conv4_b'.format(variable_field))) flatten = fluid.layers.flatten(conv4, axis=1) out = fluid.layers.fc( input=flatten, size=self.action_dim, param_attr=ParamAttr(name='{}_fc1'.format(variable_field)), bias_attr=ParamAttr(name='{}_fc1_b'.format(variable_field))) return out def act(self, state, train_or_test): sample = np.random.random() if train_or_test == 'train' and sample < self.exploration: act = np.random.randint(self.action_dim) else: if np.random.random() < 0.01: act = np.random.randint(self.action_dim) else: state = np.expand_dims(state, axis=0) pred_Q = self.exe.run(self.predict_program, feed={'state': state.astype('float32')}, fetch_list=[self.pred_value])[0] pred_Q = np.squeeze(pred_Q, axis=0) act = np.argmax(pred_Q) if train_or_test == 'train': self.exploration = max(0.1, self.exploration - 1e-6) return act def train(self, state, action, reward, next_state, isOver): if self.global_step % self.update_target_steps == 0: self.sync_target_network() self.global_step += 1 action = np.expand_dims(action, -1) self.exe.run(self.train_program, feed={ 'state': state.astype('float32'), 'action': action.astype('int32'), 'reward': reward, 'next_s': next_state.astype('float32'), 'isOver': isOver }) def sync_target_network(self): self.exe.run(self._sync_program)