Example #1
0
    def __init__(self, input_shape, nb_actions,
                 gamma=0.99, explorer=LinearEpsilonAnnealingExplorer(1, 0.1, 1000000),
                 learning_rate=0.00025, momentum=0.95, minibatch_size=32,
                 memory_size=500000, train_after=10000, train_interval=4,
                 target_update_interval=10000, monitor=True):
        self.input_shape = input_shape
        self.nb_actions = nb_actions
        self.gamma = gamma
        self._train_after = train_after
        self._train_interval = train_interval
        self._target_update_interval = target_update_interval
        self._explorer = explorer
        self._minibatch_size = minibatch_size
        self._history = History(input_shape)
        self._memory = RepMem(memory_size, input_shape[1:], 4)
        self._num_actions_taken = 0
        self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Dense(input_shape, init=he_uniform(scale=0.01)),
                Dense(input_shape),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))])

        self._action_value_net.update_signature(Tensor[input_shape])

        self._target_net = self._action_value_net.clone(CloneMethod.freeze)


        @Function
        @Signature(post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def compute_q_targets(post_states, rewards, terminals):
            return element_select(
                terminals,
                rewards,
                gamma * reduce_max(self._target_net(post_states), axis=0) + rewards,
            )

        @Function
        @Signature(pre_states=Tensor[input_shape], actions=Tensor[nb_actions],
                   post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def criterion(pre_states, actions, post_states, rewards, terminals):
            q_targets = compute_q_targets(post_states, rewards, terminals)

            q_acted = reduce_sum(self._action_value_net(pre_states) * actions, axis=0)

            return huber_loss(q_targets, q_acted, 1.0)

        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_schedule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)
        l_sgd = adam(self._action_value_net.parameters, lr_schedule,
                     momentum=m_schedule, variance_momentum=vm_schedule)

        self._metrics_writer = TensorBoardProgressWriter(freq=1, log_dir='metrics', model=criterion) if monitor else None
        self._learner = l_sgd
        self._trainer = Trainer(criterion, (criterion, None), l_sgd, self._metrics_writer)
Example #2
0
    def build_trainer(self):

        # Set the learning rate, and the momentum parameters for the Adam optimizer.
        lr = learning_rate_schedule(self.lr, UnitType.minibatch)
        beta1 = momentum_schedule(0.9)
        beta2 = momentum_schedule(0.99)

        # Calculate the losses.
        loss_on_v = cntk.squared_error(self.R, self.v)
        pi_a_s = cntk.log(cntk.times_transpose(self.pi, self.action))

        loss_on_pi = cntk.variables.Constant(-1) * (cntk.plus(
            cntk.times(pi_a_s, cntk.minus(self.R, self.v_calc)),
            0.01 * cntk.times_transpose(self.pi, cntk.log(self.pi))))
        #loss_on_pi = cntk.times(pi_a_s, cntk.minus(self.R, self.v_calc))

        self.tensorboard_v_writer = TensorBoardProgressWriter(
            freq=10, log_dir="tensorboard_v_logs", model=self.v)
        self.tensorboard_pi_writer = TensorBoardProgressWriter(
            freq=10, log_dir="tensorboard_pi_logs", model=self.pi)

        # tensorboard --logdir=tensorboard_pi_logs  http://localhost:6006/
        # tensorboard --logdir=tensorboard_v_logs  http://localhost:6006/

        # Create the trainiers.
        self.trainer_v = cntk.Trainer(self.v, (loss_on_v), [
            adam(self.pms_v,
                 lr,
                 beta1,
                 variance_momentum=beta2,
                 gradient_clipping_threshold_per_sample=2,
                 l2_regularization_weight=0.01)
        ], self.tensorboard_v_writer)
        self.trainer_pi = cntk.Trainer(self.pi, (loss_on_pi), [
            adam(self.pms_pi,
                 lr,
                 beta1,
                 variance_momentum=beta2,
                 gradient_clipping_threshold_per_sample=2,
                 l2_regularization_weight=0.01)
        ], self.tensorboard_pi_writer)
def convnet_cifar10(train_source,
                    test_source,
                    epoch_size,
                    num_convolution_layers=2,
                    minibatch_size=64,
                    max_epochs=30,
                    log_file=None,
                    tboard_log_dir='.',
                    results_path=_MODEL_PATH):
    _cntk_py.set_computation_network_trace_level(0)

    logger.info("""Running network with: 
                {num_convolution_layers} convolution layers
                {minibatch_size}  minibatch size
                for {max_epochs} epochs""".format(
        num_convolution_layers=num_convolution_layers,
        minibatch_size=minibatch_size,
        max_epochs=max_epochs))

    network = create_network(num_convolution_layers)

    progress_printer = ProgressPrinter(tag='Training',
                                       log_to_file=log_file,
                                       rank=cntk.Communicator.rank(),
                                       num_epochs=max_epochs)
    tensorboard_writer = TensorBoardProgressWriter(freq=10,
                                                   log_dir=tboard_log_dir,
                                                   model=network['output'])
    trainer = create_trainer(network, minibatch_size, epoch_size,
                             [progress_printer, tensorboard_writer])

    cv_config = CrossValidationConfig(
        minibatch_source=test_source,
        minibatch_size=16,
        callback=create_results_callback(
            os.path.join(results_path, "model_results.json"),
            num_convolution_layers=num_convolution_layers,
            minibatch_size=minibatch_size,
            max_epochs=max_epochs))
    train_and_test(network,
                   trainer,
                   train_source,
                   test_source,
                   minibatch_size,
                   epoch_size,
                   restore=False,
                   cv_config=cv_config)
    network['output'].save(os.path.join(results_path, _MODEL_NAME))
Example #4
0
    def __init__(self, input_shape, nb_actions,
                 gamma=0.99, explorer=LinearEpsilonAnnealingExplorer(1, 0.1, 1000000),
                 learning_rate=0.00025, momentum=0.95, minibatch_size=32,
                 memory_size=500000, train_after=10000, train_interval=4, target_update_interval=10000,
                 monitor=True):
        self.input_shape = input_shape
        self.nb_actions = nb_actions
        self.gamma = gamma

        self._train_after = train_after
        self._train_interval = train_interval
        self._target_update_interval = target_update_interval

        self._explorer = explorer
        self._minibatch_size = minibatch_size
        self._history = History(input_shape)
        self._memory = ReplayMemory(memory_size, input_shape[1:], 4)
        self._num_actions_taken = 0

        # Metrics accumulator
        self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

        # Action Value model (used by agent to interact with the environment)
        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Convolution2D((8, 8), 16, strides=4),
                Convolution2D((4, 4), 32, strides=2),
                Convolution2D((3, 3), 32, strides=1),
                Dense(256, init=he_uniform(scale=0.01)),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))
            ])
        self._action_value_net.update_signature(Tensor[input_shape])

        # Target model used to compute the target Q-values in training, updated
        # less frequently for increased stability.
        self._target_net = self._action_value_net.clone(CloneMethod.freeze)

        # Function computing Q-values targets as part of the computation graph
        @Function
        @Signature(post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def compute_q_targets(post_states, rewards, terminals):
            return element_select(
                terminals,
                rewards,
                gamma * reduce_max(self._target_net(post_states), axis=0) + rewards,
            )

        # Define the loss, using Huber Loss (more robust to outliers)
        @Function
        @Signature(pre_states=Tensor[input_shape], actions=Tensor[nb_actions],
                   post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def criterion(pre_states, actions, post_states, rewards, terminals):
            # Compute the q_targets
            q_targets = compute_q_targets(post_states, rewards, terminals)

            # actions is a 1-hot encoding of the action done by the agent
            q_acted = reduce_sum(self._action_value_net(pre_states) * actions, axis=0)

            # Define training criterion as the Huber Loss function
            return huber_loss(q_targets, q_acted, 1.0)

        # Adam based SGD
        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_schedule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)
        l_sgd = adam(self._action_value_net.parameters, lr_schedule,
                     momentum=m_schedule, variance_momentum=vm_schedule)

        self._metrics_writer = TensorBoardProgressWriter(freq=1, log_dir='metrics', model=criterion) if monitor else None
        self._learner = l_sgd
        self._trainer = Trainer(criterion, (criterion, None), l_sgd, self._metrics_writer)
Example #5
0
class DeepQAgent(object):
    """
    Implementation of Deep Q Neural Network agent like in:
        Nature 518. "Human-level control through deep reinforcement learning" (Mnih & al. 2015)
    """
    def __init__(self, input_shape, nb_actions,
                 gamma=0.99, explorer=LinearEpsilonAnnealingExplorer(1, 0.1, 1000000),
                 learning_rate=0.00025, momentum=0.95, minibatch_size=32,
                 memory_size=500000, train_after=10000, train_interval=4, target_update_interval=10000,
                 monitor=True):
        self.input_shape = input_shape
        self.nb_actions = nb_actions
        self.gamma = gamma

        self._train_after = train_after
        self._train_interval = train_interval
        self._target_update_interval = target_update_interval

        self._explorer = explorer
        self._minibatch_size = minibatch_size
        self._history = History(input_shape)
        self._memory = ReplayMemory(memory_size, input_shape[1:], 4)
        self._num_actions_taken = 0

        # Metrics accumulator
        self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

        # Action Value model (used by agent to interact with the environment)
        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Convolution2D((8, 8), 16, strides=4),
                Convolution2D((4, 4), 32, strides=2),
                Convolution2D((3, 3), 32, strides=1),
                Dense(256, init=he_uniform(scale=0.01)),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))
            ])
        self._action_value_net.update_signature(Tensor[input_shape])

        # Target model used to compute the target Q-values in training, updated
        # less frequently for increased stability.
        self._target_net = self._action_value_net.clone(CloneMethod.freeze)

        # Function computing Q-values targets as part of the computation graph
        @Function
        @Signature(post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def compute_q_targets(post_states, rewards, terminals):
            return element_select(
                terminals,
                rewards,
                gamma * reduce_max(self._target_net(post_states), axis=0) + rewards,
            )

        # Define the loss, using Huber Loss (more robust to outliers)
        @Function
        @Signature(pre_states=Tensor[input_shape], actions=Tensor[nb_actions],
                   post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def criterion(pre_states, actions, post_states, rewards, terminals):
            # Compute the q_targets
            q_targets = compute_q_targets(post_states, rewards, terminals)

            # actions is a 1-hot encoding of the action done by the agent
            q_acted = reduce_sum(self._action_value_net(pre_states) * actions, axis=0)

            # Define training criterion as the Huber Loss function
            return huber_loss(q_targets, q_acted, 1.0)

        # Adam based SGD
        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_schedule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)
        l_sgd = adam(self._action_value_net.parameters, lr_schedule,
                     momentum=m_schedule, variance_momentum=vm_schedule)

        self._metrics_writer = TensorBoardProgressWriter(freq=1, log_dir='metrics', model=criterion) if monitor else None
        self._learner = l_sgd
        self._trainer = Trainer(criterion, (criterion, None), l_sgd, self._metrics_writer)

    def act(self, state):
        """ This allows the agent to select the next action to perform in regard of the current state of the environment.
        It follows the terminology used in the Nature paper.

        Attributes:
            state (Tensor[input_shape]): The current environment state

        Returns: Int >= 0 : Next action to do
        """
        # Append the state to the short term memory (ie. History)
        self._history.append(state)

        # If policy requires agent to explore, sample random action
        if self._explorer.is_exploring(self._num_actions_taken):
            action = self._explorer(self.nb_actions)
        else:
            # Use the network to output the best action
            env_with_history = self._history.value
            q_values = self._action_value_net.eval(
                # Append batch axis with only one sample to evaluate
                env_with_history.reshape((1,) + env_with_history.shape)
            )

            self._episode_q_means.append(np.mean(q_values))
            self._episode_q_stddev.append(np.std(q_values))

            # Return the value maximizing the expected reward
            action = q_values.argmax()

        # Keep track of interval action counter
        self._num_actions_taken += 1
        return action

    def observe(self, old_state, action, reward, done):
        """ This allows the agent to observe the output of doing the action it selected through act() on the old_state

        Attributes:
            old_state (Tensor[input_shape]): Previous environment state
            action (int): Action done by the agent
            reward (float): Reward for doing this action in the old_state environment
            done (bool): Indicate if the action has terminated the environment
        """
        self._episode_rewards.append(reward)

        # If done, reset short term memory (ie. History)
        if done:
            # Plot the metrics through Tensorboard and reset buffers
            if self._metrics_writer is not None:
                self._plot_metrics()
            self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

            # Reset the short term memory
            self._history.reset()

        # Append to long term memory
        self._memory.append(old_state, action, reward, done)

    def train(self):
        """ This allows the agent to train itself to better understand the environment dynamics.
        The agent will compute the expected reward for the state(t+1)
        and update the expected reward at step t according to this.

        The target expectation is computed through the Target Network, which is a more stable version
        of the Action Value Network for increasing training stability.

        The Target Network is a frozen copy of the Action Value Network updated as regular intervals.
        """

        agent_step = self._num_actions_taken

        if agent_step >= self._train_after:
            if (agent_step % self._train_interval) == 0:
                pre_states, actions, post_states, rewards, terminals = self._memory.minibatch(self._minibatch_size)

                self._trainer.train_minibatch(
                    self._trainer.loss_function.argument_map(
                        pre_states=pre_states,
                        actions=Value.one_hot(actions.reshape(-1, 1).tolist(), self.nb_actions),
                        post_states=post_states,
                        rewards=rewards,
                        terminals=terminals
                    )
                )

                # Update the Target Network if needed
                if (agent_step % self._target_update_interval) == 0:
                    self._target_net = self._action_value_net.clone(CloneMethod.freeze)
                    filename = "models\model%d" % agent_step
                    self._trainer.save_checkpoint(filename)

    def _plot_metrics(self):
        """Plot current buffers accumulated values to visualize agent learning
        """
        if len(self._episode_q_means) > 0:
            mean_q = np.asscalar(np.mean(self._episode_q_means))
            self._metrics_writer.write_value('Mean Q per ep.', mean_q, self._num_actions_taken)

        if len(self._episode_q_stddev) > 0:
            std_q = np.asscalar(np.mean(self._episode_q_stddev))
            self._metrics_writer.write_value('Mean Std Q per ep.', std_q, self._num_actions_taken)

        self._metrics_writer.write_value('Sum rewards per ep.', sum(self._episode_rewards), self._num_actions_taken)
Example #6
0
def simple_mnist(tensorboard_logdir=None):
    input_dim = 19
    num_output_classes = 2
    num_hidden_layers = 2
    hidden_layers_dim = 1024

    # Input variables denoting the features and label data
    feature = C.input_variable(input_dim, np.float32)
    label = C.input_variable(num_output_classes, np.float32)

    # Instantiate the feedforward classification model
    # scaled_input = element_times(constant(0.00390625), feature)

    z = Sequential([For(range(num_hidden_layers), lambda i: Dense(hidden_layers_dim, activation=relu)),
                    Dense(num_output_classes)])(feature)

    ce = cross_entropy_with_softmax(z, label)
    pe = classification_error(z, label)

    data_dir = r"."

    path = os.path.normpath(os.path.join(data_dir, "train.ctf"))
    check_path(path)

    reader_train = create_reader(path, True, input_dim, num_output_classes)

    input_map = {
        feature  : reader_train.streams.features,
        label  : reader_train.streams.labels
    }

    # Training config
    minibatch_size = 512
    num_samples_per_sweep = 1825000
    num_sweeps_to_train_with = 100

    # Instantiate progress writers.
    progress_writers = [ProgressPrinter(
        tag='Training',
        num_epochs=num_sweeps_to_train_with)]

    if tensorboard_logdir is not None:
        tensorboard_writer = TensorBoardProgressWriter(freq=10, log_dir=tensorboard_logdir, model=z)
        progress_writers.append(tensorboard_writer)

    # Instantiate the trainer object to drive the model training
    lr = learning_parameter_schedule_per_sample(0.001)
    learner = create_learner(model=z)
    trainer = Trainer(z, (ce, pe), learner, progress_writers)

    num_minibatches_to_train = int(num_samples_per_sweep / minibatch_size * num_sweeps_to_train_with)

    model_dir = "model"
    for i in range(num_minibatches_to_train):
        mb = reader_train.next_minibatch(minibatch_size, input_map=input_map)
        trainer.train_minibatch(mb)

        freq = int(num_samples_per_sweep / minibatch_size)
        if i > 0 and i % freq == 0:
            timestamp = datetime.datetime.now().strftime("%Y_%m_%d_%H_%M_%S_%f")
            current_trainer_cp = os.path.join(model_dir, timestamp + "_epoch_" + str(freq) + ".trainer")
            trainer.save_checkpoint(current_trainer_cp)

            train_error = get_error_rate(os.path.join(data_dir, "train_subset.ctf"), input_map, input_dim,
                                         num_output_classes, trainer)
            valid_error = get_error_rate(os.path.join(data_dir, "validation.ctf"), input_map, input_dim, num_output_classes,
                                         trainer)

            if train_error > 0:
                tensorboard_writer.write_value("train_error", train_error, i)
            if valid_error > 0:
                tensorboard_writer.write_value("valid_error", valid_error, i)

    feat_path = os.path.normpath(os.path.join(data_dir, "test.ctf"))
    return get_error_rate(feat_path, input_map, input_dim, num_output_classes, trainer)
Example #7
0
def simple_mnist(tensorboard_logdir=None):
    input_dim = 784
    num_output_classes = 10
    num_hidden_layers = 2
    hidden_layers_dim = 200

    # Input variables denoting the features and label data
    feature = C.input_variable(input_dim, np.float32)
    label = C.input_variable(num_output_classes, np.float32)

    # Instantiate the feedforward classification model
    scaled_input = element_times(constant(0.00390625), feature)

    z = Sequential([
        For(range(num_hidden_layers),
            lambda i: Dense(hidden_layers_dim, activation=relu)),
        Dense(num_output_classes)
    ])(scaled_input)

    ce = cross_entropy_with_softmax(z, label)
    pe = classification_error(z, label)

    data_dir = os.path.dirname(os.path.abspath(__file__))
    path = os.path.join(data_dir, 'Train-28x28_cntk_text.txt')

    reader_train = create_reader(path, True, input_dim, num_output_classes)

    input_map = {
        feature: reader_train.streams.features,
        label: reader_train.streams.labels
    }

    # Training config
    minibatch_size = 64
    num_samples_per_sweep = 60000
    num_sweeps_to_train_with = 10

    # Instantiate progress writers.
    # training_progress_output_freq = 100
    progress_writers = [
        ProgressPrinter(
            # freq=training_progress_output_freq,
            tag='Training',
            num_epochs=num_sweeps_to_train_with)
    ]

    if tensorboard_logdir is not None:
        progress_writers.append(
            TensorBoardProgressWriter(freq=10,
                                      log_dir=tensorboard_logdir,
                                      model=z))

    # Instantiate the trainer object to drive the model training
    lr = 0.001
    trainer = Trainer(z, (ce, pe), sgd(z.parameters, lr), progress_writers)

    training_session(trainer=trainer,
                     mb_source=reader_train,
                     mb_size=minibatch_size,
                     model_inputs_to_streams=input_map,
                     max_samples=num_samples_per_sweep *
                     num_sweeps_to_train_with,
                     progress_frequency=num_samples_per_sweep).train()

    # Load test data
    path = os.path.normpath(os.path.join(data_dir, "Test-28x28_cntk_text.txt"))
    check_path(path)

    reader_test = create_reader(path, False, input_dim, num_output_classes)

    input_map = {
        feature: reader_test.streams.features,
        label: reader_test.streams.labels
    }

    # Test data for trained model
    C.debugging.start_profiler()
    C.debugging.enable_profiler()
    C.debugging.set_node_timing(True)

    test_minibatch_size = 1024
    num_samples = 10000
    num_minibatches_to_test = num_samples / test_minibatch_size
    test_result = 0.0
    for i in range(0, int(num_minibatches_to_test)):
        mb = reader_test.next_minibatch(test_minibatch_size,
                                        input_map=input_map)
        eval_error = trainer.test_minibatch(mb)
        test_result = test_result + eval_error

    C.debugging.stop_profiler()
    trainer.print_node_timing()

    # Average of evaluation errors of all test minibatches
    return test_result * 100 / num_minibatches_to_test
def train_test(train_reader,
               test_reader,
               model_func,
               x,
               y,
               learning_rate,
               minibatch_size,
               num_sweeps_to_train_with=10,
               tensorboard_logdir=None):

    # Instantiate the model function; x is the input (feature) variable
    model = model_func(x)

    # Instantiate the Tensorboard writer
    tensorboard_writer = None
    if tensorboard_logdir is not None:
        tensorboard_writer = TensorBoardProgressWriter(
            freq=10, log_dir=tensorboard_logdir, model=model)

    # Instantiate the loss and error function
    loss, label_error = create_criterion_function(model, y)

    # Instantiate the trainer object to drive the model training
    #learning_rate = 0.2
    lr_schedule = C.learning_parameter_schedule(learning_rate)
    learner = C.sgd(z.parameters, lr_schedule)
    trainer = C.Trainer(z, (loss, label_error), [learner],
                        progress_writers=tensorboard_writer)

    # Initialize the parameters for the trainer
    #minibatch_size = 64
    num_samples_per_sweep = 60000
    num_minibatches_to_train = (num_samples_per_sweep *
                                num_sweeps_to_train_with) / minibatch_size

    # Map the data streams to the input and labels.
    input_map = {
        y: train_reader.streams.labels,
        x: train_reader.streams.features
    }

    # Uncomment below for more detailed logging
    training_progress_output_freq = 500

    # Start a timer
    start = time.time()

    for i in range(0, int(num_minibatches_to_train)):
        # Read a mini batch from the training data file
        data = train_reader.next_minibatch(minibatch_size, input_map=input_map)
        trainer.train_minibatch(data)
        print_training_progress(trainer,
                                i,
                                training_progress_output_freq,
                                verbose=1)

    # Print training time
    print("Training took {:.1f} sec".format(time.time() - start))

    # Test the model
    test_input_map = {
        y: test_reader.streams.labels,
        x: test_reader.streams.features
    }

    # Test data for trained model
    test_minibatch_size = 512
    num_samples = 10000
    num_minibatches_to_test = num_samples // test_minibatch_size

    test_result = 0.0

    for i in range(num_minibatches_to_test):

        # We are loading test data in batches specified by test_minibatch_size
        # Each data point in the minibatch is a MNIST digit image of 784 dimensions
        # with one pixel per dimension that we will encode / decode with the
        # trained model.
        data = test_reader.next_minibatch(test_minibatch_size,
                                          input_map=test_input_map)
        eval_error = trainer.test_minibatch(data)
        test_result = test_result + eval_error

    # Average of evaluation errors of all test minibatches
    print("Average test error: {0:.2f}%".format(test_result * 100 /
                                                num_minibatches_to_test))
Example #9
0
    def __init__(self,
                 state_dim,
                 action_dim,
                 gamma=0.99,
                 learning_rate=1e-4,
                 momentum=0.95):
        self.state_dim = state_dim
        self.action_dim = action_dim
        self.gamma = gamma

        with default_options(activation=relu, init=he_uniform()):
            # Convolution filter counts were halved to save on memory, no gpu :(
            self.model = Sequential([
                Convolution2D((8, 8), 16, strides=4, name='conv1'),
                Convolution2D((4, 4), 32, strides=2, name='conv2'),
                Convolution2D((3, 3), 32, strides=1, name='conv3'),
                Dense(256, init=he_uniform(scale=0.01), name='dense1'),
                Dense(action_dim,
                      activation=None,
                      init=he_uniform(scale=0.01),
                      name='actions')
            ])
            self.model.update_signature(Tensor[state_dim])

        # Create the target model as a copy of the online model
        self.target_model = None
        self.update_target()

        self.pre_states = input_variable(state_dim, name='pre_states')
        self.actions = input_variable(action_dim, name='actions')
        self.post_states = input_variable(state_dim, name='post_states')
        self.rewards = input_variable((), name='rewards')
        self.terminals = input_variable((), name='terminals')
        self.is_weights = input_variable((), name='is_weights')

        predicted_q = reduce_sum(self.model(self.pre_states) * self.actions,
                                 axis=0)

        # DQN - calculate target q values
        # post_q = reduce_max(self.target_model(self.post_states), axis=0)

        # DDQN - calculate target q values
        online_selection = one_hot(
            argmax(self.model(self.post_states), axis=0), self.action_dim)
        post_q = reduce_sum(self.target_model(self.post_states) *
                            online_selection,
                            axis=0)

        post_q = (1.0 - self.terminals) * post_q
        target_q = stop_gradient(self.rewards + self.gamma * post_q)

        # Huber loss
        delta = 1.0
        self.td_error = minus(predicted_q, target_q, name='td_error')
        abs_error = abs(self.td_error)
        errors = element_select(less(abs_error, delta),
                                square(self.td_error) * 0.5,
                                delta * (abs_error - 0.5 * delta))
        loss = errors * self.is_weights

        # Adam based SGD
        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_scheule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)

        self._learner = adam(self.model.parameters,
                             lr_schedule,
                             m_scheule,
                             variance_momentum=vm_schedule)
        self.writer = TensorBoardProgressWriter(log_dir='metrics',
                                                model=self.model)
        self.trainer = Trainer(self.model, (loss, None), [self._learner],
                               self.writer)
Example #10
0
class DeepQAgent(object):
    """
    Implementation of Deep Q Neural Network agent like in:
        Nature 518. "Human-level control through deep reinforcement learning" (Mnih & al. 2015)
    """
    def __init__(self, input_shape, nb_actions,
                 gamma=0.95, explorer=LinearEpsilonAnnealingExplorer(1, 0.1, 100000),
                 learning_rate=0.01, momentum=0.8, minibatch_size=16,
                 memory_size=15000, train_after=100, train_interval=100, target_update_interval=500,
                 monitor=True):
        self.input_shape = input_shape
        self.nb_actions = nb_actions
        self.gamma = gamma

        self._train_after = train_after
        self._train_interval = train_interval
        self._target_update_interval = target_update_interval

        self._explorer = explorer
        self._minibatch_size = minibatch_size
        self._history = History(input_shape)
        self._memory = ReplayMemory(memory_size, input_shape[1:], 4)
        self._num_actions_taken = 0
        self._num_trains = 0

        # Metrics accumulator
        self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

        '''
        # Action Value model (used by agent to interact with the environment)
        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Convolution2D((8, 8), 16, strides=4),
                Convolution2D((4, 4), 32, strides=2),
                Convolution2D((3, 3), 32, strides=1),
                Dense(256, init=he_uniform(scale=0.01)),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))
            ])
        ''' 
        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Dense(7, init=he_uniform(scale=0.01)),
                Dense(8, init=he_uniform(scale=0.01)),
                #Dense(16, init=he_uniform(scale=0.01)),
                #Dense(32, init=he_uniform(scale=0.01)),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))
            ])
        
        self._action_value_net.update_signature(Tensor[input_shape])

        # Target model used to compute the target Q-values in training, updated
        # less frequently for increased stability.
        self._target_net = self._action_value_net.clone(CloneMethod.freeze)

        # Function computing Q-values targets as part of the computation graph
        @Function
        @Signature(post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def compute_q_targets(post_states, rewards, terminals):
            return element_select(
                terminals,
                rewards,
                gamma * reduce_max(self._target_net(post_states), axis=0) + rewards,
            )

        # Define the loss, using Huber Loss (more robust to outliers)
        @Function
        @Signature(pre_states=Tensor[input_shape], actions=Tensor[nb_actions],
                   post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def criterion(pre_states, actions, post_states, rewards, terminals):
            # Compute the q_targets
            q_targets = compute_q_targets(post_states, rewards, terminals)

            # actions is a 1-hot encoding of the action done by the agent
            q_acted = reduce_sum(self._action_value_net(pre_states) * actions, axis=0)

            # Define training criterion as the Huber Loss function
            return huber_loss(q_targets, q_acted, 1.0)

        # Adam based SGD
        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_schedule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)
        l_sgd = adam(self._action_value_net.parameters, lr_schedule,
                     momentum=m_schedule, variance_momentum=vm_schedule)

        self._metrics_writer = TensorBoardProgressWriter(freq=1, log_dir='metrics', model=criterion) if monitor else None
        self._learner = l_sgd
        self._trainer = Trainer(criterion, (criterion, None), l_sgd, self._metrics_writer)

        #self._trainer.restore_from_checkpoint('models/oldmodels/model800000')

    def act(self, state):
        """ This allows the agent to select the next action to perform in regard of the current state of the environment.
        It follows the terminology used in the Nature paper.

        Attributes:
            state (Tensor[input_shape]): The current environment state

        Returns: Int >= 0 : Next action to do
        """
        # Append the state to the short term memory (ie. History)
        self._history.append(state)

        # If policy requires agent to explore, sample random action
        if self._explorer.is_exploring(self._num_actions_taken):
            action = self._explorer(self.nb_actions)
        else:
            # Use the network to output the best action
            env_with_history = self._history.value
            q_values = self._action_value_net.eval(
                # Append batch axis with only one sample to evaluate
                env_with_history.reshape((1,) + env_with_history.shape)
            )

            self._episode_q_means.append(np.mean(q_values))
            self._episode_q_stddev.append(np.std(q_values))

            # Return the value maximizing the expected reward
            action = q_values.argmax()

        # Keep track of interval action counter
        self._num_actions_taken += 1
        #print(self._num_actions_taken)
        return action

    def observe(self, old_state, action, reward, done):
        """ This allows the agent to observe the output of doing the action it selected through act() on the old_state

        Attributes:
            old_state (Tensor[input_shape]): Previous environment state
            action (int): Action done by the agent
            reward (float): Reward for doing this action in the old_state environment
            done (bool): Indicate if the action has terminated the environment
        """
        self._episode_rewards.append(reward)

        # If done, reset short term memory (ie. History)
        if done:
            # Plot the metrics through Tensorboard and reset buffers
            if self._metrics_writer is not None:
                self._plot_metrics()
            self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

            # Reset the short term memory
            self._history.reset()

        # Append to long term memory
        self._memory.append(old_state, action, reward, done)

    def train(self):
        """ This allows the agent to train itself to better understand the environment dynamics.
        The agent will compute the expected reward for the state(t+1)
        and update the expected reward at step t according to this.

        The target expectation is computed through the Target Network, which is a more stable version
        of the Action Value Network for increasing training stability.

        The Target Network is a frozen copy of the Action Value Network updated as regular intervals.
        """

        agent_step = self._num_actions_taken

        if agent_step >= self._train_after:
            #if (agent_step % self._train_interval) == 0:
            print('\nTraining minibatch\n')
            client.setCarControls(zero_controls)
            pre_states, actions, post_states, rewards, terminals = self._memory.minibatch(self._minibatch_size)
            self._trainer.train_minibatch(
                self._trainer.loss_function.argument_map(
                    pre_states=pre_states,
                    actions=Value.one_hot(actions.reshape(-1, 1).tolist(), self.nb_actions),
                    post_states=post_states,
                    rewards=rewards,
                    terminals=terminals
                )
            )
            self._num_trains += 1
            # Update the Target Network if needed
            if self._num_trains % 20 == 0:
                print('updating network')
                self._target_net = self._action_value_net.clone(CloneMethod.freeze)
                filename = dirname+"\model%d" % agent_step
                self._trainer.save_checkpoint(filename)
    
    def _plot_metrics(self):
        """Plot current buffers accumulated values to visualize agent learning
        """
        if len(self._episode_q_means) > 0:
            mean_q = np.asscalar(np.mean(self._episode_q_means))
            self._metrics_writer.write_value('Mean Q per ep.', mean_q, self._num_actions_taken)

        if len(self._episode_q_stddev) > 0:
            std_q = np.asscalar(np.mean(self._episode_q_stddev))
            self._metrics_writer.write_value('Mean Std Q per ep.', std_q, self._num_actions_taken)

        self._metrics_writer.write_value('Sum rewards per ep.', sum(self._episode_rewards), self._num_actions_taken)
Example #11
0
    def __init__(self,
                 state_shape,
                 action_count,
                 model_func,
                 vmin,
                 vmax,
                 n,
                 gamma=0.99,
                 lr=0.00025,
                 mm=0.95,
                 use_tensorboard=False):
        """
        Creates a new agent that learns using Categorical DQN as described in
        "A Distributional Perspective on Reinforcement Learning"
        :param state_shape: The shape of each input shape e.g. (4 x 84 x 84) for Atari
        :param action_count: The number of actions e.g. 14
        :param model_func: The model to train
        :param vmin: Minimum value of return distribution
        :param vmax: Maximum value of return distribution
        :param n: Number of support atoms
        :param gamma: Discount factor for Bellman update
        :param lr: The learning rate for Adam SGD
        :param mm: The momentum for Adam SGD
        """
        self.state_shape = state_shape
        self.action_count = action_count
        self.gamma = gamma
        self.learning_rate = lr
        self.momentum = mm

        # Distribution parameters
        self.vmin = vmin
        self.vmax = vmax
        self.n = n
        self.dz = (vmax - vmin) / (n - 1)

        # Support atoms
        self.z = np.linspace(vmin, vmax, n, dtype=np.float32)

        # Model input and output
        self.state_var = C.input_variable(self.state_shape, name='state')
        self.action_return_dist = C.input_variable((self.action_count, n),
                                                   name='ar_dist')

        # Model output assigns a probability to each support atom for each action
        self.raw = model_func(self.state_var)
        self.model = C.softmax(self.raw, axis=1)

        # Adam-based SGD with cross-entropy loss
        loss = C.cross_entropy_with_softmax(self.raw,
                                            self.action_return_dist,
                                            axis=1,
                                            name='loss')
        lr_schedule = C.learning_rate_schedule(self.learning_rate,
                                               C.UnitType.sample)
        mom_schedule = C.momentum_schedule(self.momentum)
        vm_schedule = C.momentum_schedule(0.999)
        learner = C.adam(self.raw.parameters,
                         lr_schedule,
                         mom_schedule,
                         variance_momentum=vm_schedule)

        if use_tensorboard:
            self.writer = TensorBoardProgressWriter(log_dir='metrics',
                                                    model=self.model)
        else:
            self.writer = None

        self.trainer = C.Trainer(self.raw, (loss, None), [learner],
                                 self.writer)

        # Create target network as copy of online network
        self.target_model = None
        self.update_target()
Example #12
0
class DQAgent(object):
    """docstring for DQAgent"""                                                             ############should modify @!@!
    def __init__(self, input_shape, nb_actions,
                 gamma=0.99, explorer=LinearEpsilonAnnealingExplorer(1, 0.1, 1000000),
                 learning_rate=0.00025, momentum=0.95, minibatch_size=32,
                 memory_size=500000, train_after=10000, train_interval=4,
                 target_update_interval=10000, monitor=True):
        self.input_shape = input_shape
        self.nb_actions = nb_actions
        self.gamma = gamma
        self._train_after = train_after
        self._train_interval = train_interval
        self._target_update_interval = target_update_interval
        self._explorer = explorer
        self._minibatch_size = minibatch_size
        self._history = History(input_shape)
        self._memory = RepMem(memory_size, input_shape[1:], 4)
        self._num_actions_taken = 0
        self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Dense(input_shape, init=he_uniform(scale=0.01)),
                Dense(input_shape),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))])

        self._action_value_net.update_signature(Tensor[input_shape])

        self._target_net = self._action_value_net.clone(CloneMethod.freeze)


        @Function
        @Signature(post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def compute_q_targets(post_states, rewards, terminals):
            return element_select(
                terminals,
                rewards,
                gamma * reduce_max(self._target_net(post_states), axis=0) + rewards,
            )

        @Function
        @Signature(pre_states=Tensor[input_shape], actions=Tensor[nb_actions],
                   post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def criterion(pre_states, actions, post_states, rewards, terminals):
            q_targets = compute_q_targets(post_states, rewards, terminals)

            q_acted = reduce_sum(self._action_value_net(pre_states) * actions, axis=0)

            return huber_loss(q_targets, q_acted, 1.0)

        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_schedule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)
        l_sgd = adam(self._action_value_net.parameters, lr_schedule,
                     momentum=m_schedule, variance_momentum=vm_schedule)

        self._metrics_writer = TensorBoardProgressWriter(freq=1, log_dir='metrics', model=criterion) if monitor else None
        self._learner = l_sgd
        self._trainer = Trainer(criterion, (criterion, None), l_sgd, self._metrics_writer)

    def act(self, state):
        self._history.append(state)

        if self._explorer.is_exploring(self._num_actions_taken):
            action = self._explorer(self.nb_actions)
        else:
            env_with_history = self._history.value
            q_values = self._action_value_net.eval(
                env_with_history.reshape((1,) + env_with_history.shape)
            )

            self._episode_q_means.append(np.mean(q_values))
            self._episode_q_stddev.append(np.std(q_values))
            action = q_values.argmax()

        self._num_actions_taken += 1
        return action

    def observe(self, old_state, action, reward, done):
        self._episode_rewards.append(reward)

        if done:
            if self._metrics_writer is not None:
                self._plot_metrics()
            self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

            self._history.reset()

        self._memory.append(old_state, action, reward, done)

    def train(self):

        agent_step = self._num_actions_taken

        if agent_step >= self._train_after:
            if (agent_step % self._train_interval) == 0:
                pre_states, actions, post_states, rewards, terminals = self._memory.minibatch(self._minibatch_size)

                self._trainer.train_minibatch(
                    self._trainer.loss_function.argument_map(
                        pre_states=pre_states,
                        actions=Value.one_hot(actions.reshape(-1,1).tolist(), self.nb_actions),
                        post_states=post_states,
                        rewards=rewards,
                        terminals=terminals
                    )
                )

            if (agent_step % self._target_update_interval) == 0:
                self._target_net = self._action_value_net.clone(CloneMethod.freeze)
                filename = "model\model%d" % agent_step # save ???? not good at using %d
                self._trainer.save_checkpoint(filename)

    def _plot_metrics(self):

        if len(self._episode_q_means) > 0:
            mean_q = np.asscalar(np.mean(self._episode_q_means))
            self._metrics_writer.write_value('Mean Q per ep.', mean_q, self._num_actions_taken)

        if len(self._episode_q_stddev) > 0:
            std_q = np.asscalar(np.mean(self._episode_q_stddev))
            self._metrics_writer.write_value('Mean Std Q per ep.', std_q, self._num_actions_taken)

        self._metrics_writer.write_value('Sum rewards per ep', sum(self._episode_rewards), self._num_actions_taken)
Example #13
0
class DeepQAgent(object):
    """
    Implementation of Deep Q Neural Network agent like in:
        Nature 518. "Human-level control through deep reinforcement learning" (Mnih & al. 2015)
    """
    def __init__(self,
                 input_shape,
                 nb_actions,
                 gamma=0.99,
                 explorer=LinearEpsilonAnnealingExplorer(1, 0.1, 1000000),
                 learning_rate=0.00025,
                 momentum=0.95,
                 minibatch_size=32,
                 memory_size=500000,
                 train_after=200000,
                 train_interval=4,
                 target_update_interval=10000,
                 monitor=True):
        self.input_shape = input_shape
        self.nb_actions = nb_actions
        self.gamma = gamma

        self._train_after = train_after
        self._train_interval = train_interval
        self._target_update_interval = target_update_interval

        self._explorer = explorer
        self._minibatch_size = minibatch_size
        self._history = History(input_shape)
        self._memory = ReplayMemory(memory_size, input_shape[1:], 4)
        self._num_actions_taken = 0

        # Metrics accumulator
        self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

        # Action Value model (used by agent to interact with the environment)
        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Convolution2D((8, 8), 16, strides=4),
                Convolution2D((4, 4), 32, strides=2),
                Convolution2D((3, 3), 32, strides=1),
                Dense(256, init=he_uniform(scale=0.01)),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))
            ])
        self._action_value_net.update_signature(Tensor[input_shape])

        # Target model used to compute the target Q-values in training, updated
        # less frequently for increased stability.
        self._target_net = self._action_value_net.clone(CloneMethod.freeze)

        # Function computing Q-values targets as part of the computation graph
        @Function
        @Signature(post_states=Tensor[input_shape],
                   rewards=Tensor[()],
                   terminals=Tensor[()])
        def compute_q_targets(post_states, rewards, terminals):
            return element_select(
                terminals,
                rewards,
                gamma * reduce_max(self._target_net(post_states), axis=0) +
                rewards,
            )

        # Define the loss, using Huber Loss (more robust to outliers)
        @Function
        @Signature(pre_states=Tensor[input_shape],
                   actions=Tensor[nb_actions],
                   post_states=Tensor[input_shape],
                   rewards=Tensor[()],
                   terminals=Tensor[()])
        def criterion(pre_states, actions, post_states, rewards, terminals):
            # Compute the q_targets
            q_targets = compute_q_targets(post_states, rewards, terminals)

            # actions is a 1-hot encoding of the action done by the agent
            q_acted = reduce_sum(self._action_value_net(pre_states) * actions,
                                 axis=0)

            # Define training criterion as the Huber Loss function
            return huber_loss(q_targets, q_acted, 1.0)

        # Adam based SGD
        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_schedule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)
        l_sgd = adam(self._action_value_net.parameters,
                     lr_schedule,
                     momentum=m_schedule,
                     variance_momentum=vm_schedule)

        self._metrics_writer = TensorBoardProgressWriter(
            freq=1, log_dir='metrics', model=criterion) if monitor else None
        self._learner = l_sgd
        self._trainer = Trainer(criterion, (criterion, None), l_sgd,
                                self._metrics_writer)

    def load(self, model_path):

        self._trainer.restore_from_checkpoint(model_path)

    def act(self, state, eval=False):
        """ This allows the agent to select the next action to perform in regard of the current state of the environment.
        It follows the terminology used in the Nature paper.

        Attributes:
            state (Tensor[input_shape]): The current environment state

        Returns: Int >= 0 : Next action to do
        """
        # Append the state to the short term memory (ie. History)
        self._history.append(state)

        # If policy requires agent to explore, sample random action
        if self._explorer.is_exploring(self._num_actions_taken) and not eval:
            action = self._explorer(self.nb_actions)
            q_values = None
        else:
            # Use the network to output the best action
            env_with_history = self._history.value
            q_values = self._action_value_net.eval(
                # Append batch axis with only one sample to evaluate
                env_with_history.reshape((1, ) + env_with_history.shape))

            self._episode_q_means.append(np.mean(q_values))
            self._episode_q_stddev.append(np.std(q_values))

            # Return the value maximizing the expected reward
            action = q_values.argmax()

        # Keep track of interval action counter
        self._num_actions_taken += 1
        return action, q_values

    def observe(self, old_state, action, reward, done):
        """ This allows the agent to observe the output of doing the action it selected through act() on the old_state

        Attributes:
            old_state (Tensor[input_shape]): Previous environment state
            action (int): Action done by the agent
            reward (float): Reward for doing this action in the old_state environment
            done (bool): Indicate if the action has terminated the environment
        """
        self._episode_rewards.append(reward)

        # If done, reset short term memory (ie. History)
        if done:
            # Plot the metrics through Tensorboard and reset buffers
            if self._metrics_writer is not None:
                self._plot_metrics()
            self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

            # Reset the short term memory
            self._history.reset()

        # Append to long term memory
        self._memory.append(old_state, action, reward, done)

    def train(self, checkpoint_dir):
        """ This allows the agent to train itself to better understand the environment dynamics.
        The agent will compute the expected reward for the state(t+1)
        and update the expected reward at step t according to this.

        The target expectation is computed through the Target Network, which is a more stable version
        of the Action Value Network for increasing training stability.

        The Target Network is a frozen copy of the Action Value Network updated as regular intervals.
        """

        agent_step = self._num_actions_taken

        if agent_step >= self._train_after:
            if (agent_step % self._train_interval) == 0:
                #print('training... number of steps: {}'.format(agent_step))

                pre_states, actions, post_states, rewards, terminals = self._memory.minibatch(
                    self._minibatch_size)
                self._trainer.train_minibatch(
                    self._trainer.loss_function.argument_map(
                        pre_states=pre_states,
                        actions=Value.one_hot(
                            actions.reshape(-1, 1).tolist(), self.nb_actions),
                        post_states=post_states,
                        rewards=rewards,
                        terminals=terminals))

                # Update the Target Network if needed
                if (agent_step % self._target_update_interval) == 0:
                    self._target_net = self._action_value_net.clone(
                        CloneMethod.freeze)
                    filename = os.path.join(checkpoint_dir,
                                            "models\model%d" % agent_step)
                    self._trainer.save_checkpoint(filename)

    def _plot_metrics(self):
        """Plot current buffers accumulated values to visualize agent learning
        """
        if len(self._episode_q_means) > 0:
            mean_q = np.asscalar(np.mean(self._episode_q_means))
            self._metrics_writer.write_value('Mean Q per ep.', mean_q,
                                             self._num_actions_taken)

        if len(self._episode_q_stddev) > 0:
            std_q = np.asscalar(np.mean(self._episode_q_stddev))
            self._metrics_writer.write_value('Mean Std Q per ep.', std_q,
                                             self._num_actions_taken)

        self._metrics_writer.write_value('Sum rewards per ep.',
                                         sum(self._episode_rewards),
                                         self._num_actions_taken)

    def get_depth_image(self, client):
        # get depth image from airsim
        responses = client.simGetImages([
            airsim.ImageRequest("RCCamera", airsim.ImageType.DepthPerspective,
                                True, False)
        ])

        img1d = np.array(responses[0].image_data_float, dtype=np.float)
        img1d = 255 / np.maximum(np.ones(img1d.size), img1d)
        if img1d.size > 1:

            img2d = np.reshape(img1d,
                               (responses[0].height, responses[0].width))

            image = Image.fromarray(img2d)
            im_final = np.array(image.resize((84, 84)).convert('L'))
            im_final = im_final / 255.0

            return im_final

        return np.zeros((84, 84)).astype(float)

    # Gets a coverage image from AirSim
    def get_cov_image(self, coverage_map):

        state, cov_reward = coverage_map.get_state_from_pose()
        #state = self.coverage_map.get_map_scaled()

        # debug only
        #im = Image.fromarray(np.uint8(state))
        #im.save("DistributedRL\\debug\\{}.png".format(time.time()))

        # normalize state
        state = state / 255.0

        return state, cov_reward
Example #14
0
def convnet_mnist(debug_output=False,
                  epoch_size=60000,
                  minibatch_size=64,
                  max_epochs=10):
    image_height = 28
    image_width = 28
    num_channels = 1
    input_dim = image_height * image_width * num_channels
    num_output_classes = 10

    # Input variables denoting the features and label data
    input_var = C.ops.input_variable((num_channels, image_height, image_width),
                                     np.float32)
    label_var = C.ops.input_variable(num_output_classes, np.float32)

    # Instantiate the feedforward classification model
    scaled_input = C.ops.element_times(C.ops.constant(0.00390625), input_var)

    with C.layers.default_options(activation=C.ops.relu, pad=False):
        conv1 = C.layers.Convolution2D((5, 5), 32, pad=True)(scaled_input)
        pool1 = C.layers.MaxPooling((3, 3), (2, 2))(conv1)
        conv2 = C.layers.Convolution2D((3, 3), 48)(pool1)
        pool2 = C.layers.MaxPooling((3, 3), (2, 2))(conv2)
        conv3 = C.layers.Convolution2D((3, 3), 64)(pool2)
        f4 = C.layers.Dense(96)(conv3)
        drop4 = C.layers.Dropout(0.5)(f4)
        z = C.layers.Dense(num_output_classes, activation=C.ops.sigmoid)(drop4)

    ce = C.losses.cross_entropy_with_softmax(z, label_var)
    pe = C.metrics.classification_error(z, label_var)

    reader_train = create_reader(
        os.path.join(data_dir, 'Train-28x28_cntk_text.txt'), True, input_dim,
        num_output_classes)

    # Set learning parameters
    lr_per_sample = [0.001] * 10 + [0.0005] * 10 + [0.0001]
    lr_schedule = C.learning_rate_schedule(lr_per_sample,
                                           C.learners.UnitType.sample,
                                           epoch_size)
    mm_time_constant = [0] * 5 + [1024]
    mm_schedule = C.learners.momentum_as_time_constant_schedule(
        mm_time_constant, epoch_size)

    # Instantiate the trainer object to drive the model training
    learner = C.learners.momentum_sgd(z.parameters, lr_schedule, mm_schedule)
    progress_printers = [
        C.logging.ProgressPrinter(tag='Training', num_epochs=max_epochs)
    ]
    progress_printers.append(
        TensorBoardProgressWriter(freq=10, log_dir=log_dir, model=z))

    trainer = C.Trainer(z, (ce, pe), learner, progress_printers)

    # define mapping from reader streams to network inputs
    input_map = {
        input_var: reader_train.streams.features,
        label_var: reader_train.streams.labels
    }

    C.logging.log_number_of_parameters(z)
    print()

    # Get minibatches of images to train with and perform model training
    for epoch in range(max_epochs):  # loop over epochs
        sample_count = 0
        while sample_count < epoch_size:  # loop over minibatches in the epoch
            data = reader_train.next_minibatch(
                min(minibatch_size, epoch_size - sample_count),
                input_map=input_map)  # fetch minibatch.
            trainer.train_minibatch(data)  # update model with it
            sample_count += data[
                label_var].num_samples  # count samples processed so far

        trainer.summarize_training_progress()
        z.save(
            os.path.join(output_dir,
                         "digit_epoch_{}.checkpoint".format(epoch)))

    # Load test data
    reader_test = create_reader(
        os.path.join(data_dir, 'Test-28x28_cntk_text.txt'), False, input_dim,
        num_output_classes)
    z.save(os.path.join(output_dir, "digit.model"))

    input_map = {
        input_var: reader_test.streams.features,
        label_var: reader_test.streams.labels
    }

    # Test data for trained model
    epoch_size = 10000
    minibatch_size = 1024

    # process minibatches and evaluate the model
    metric_numer = 0
    metric_denom = 0
    sample_count = 0
    minibatch_index = 0

    while sample_count < epoch_size:
        current_minibatch = min(minibatch_size, epoch_size - sample_count)

        # Fetch next test min batch.
        data = reader_test.next_minibatch(current_minibatch,
                                          input_map=input_map)

        # minibatch data to be trained with
        metric_numer += trainer.test_minibatch(data) * current_minibatch
        metric_denom += current_minibatch

        # Keep track of the number of samples processed so far.
        sample_count += data[label_var].num_samples
        minibatch_index += 1

    print("")
    print("Final Results: Minibatch[1-{}]: errs = {:0.2f}% * {}".format(
        minibatch_index + 1, (metric_numer * 100.0) / metric_denom,
        metric_denom))
    print("")

    return metric_numer / metric_denom
def train_model(image_input,
                roi_input,
                dims_input,
                loss,
                pred_error,
                lr_per_sample,
                mm_schedule,
                l2_reg_weight,
                epochs_to_train,
                cfg,
                rpn_rois_input=None,
                buffered_rpn_proposals=None):
    if isinstance(loss, cntk.Variable):
        loss = combine([loss])

    params = loss.parameters
    biases = [p for p in params if '.b' in p.name or 'b' == p.name]
    others = [p for p in params if not p in biases]
    bias_lr_mult = cfg["CNTK"].BIAS_LR_MULT

    if cfg["CNTK"].DEBUG_OUTPUT:
        print("biases")
        for p in biases:
            print(p)
        print("others")
        for p in others:
            print(p)
        print("bias_lr_mult: {}".format(bias_lr_mult))

    # Instantiate the learners and the trainer object
    lr_schedule = learning_parameter_schedule_per_sample(lr_per_sample)
    learner = momentum_sgd(others,
                           lr_schedule,
                           mm_schedule,
                           l2_regularization_weight=l2_reg_weight,
                           unit_gain=False,
                           use_mean_gradient=True)

    bias_lr_per_sample = [v * bias_lr_mult for v in lr_per_sample]
    bias_lr_schedule = learning_parameter_schedule_per_sample(
        bias_lr_per_sample)
    bias_learner = momentum_sgd(biases,
                                bias_lr_schedule,
                                mm_schedule,
                                l2_regularization_weight=l2_reg_weight,
                                unit_gain=False,
                                use_mean_gradient=True)
    trainer = Trainer(None, (loss, pred_error), [learner, bias_learner])

    # Get minibatches of images and perform model training
    print("Training model for %s epochs." % epochs_to_train)
    log_number_of_parameters(loss)

    # Create the minibatch source
    if buffered_rpn_proposals is not None:
        proposal_provider = ProposalProvider.fromlist(buffered_rpn_proposals,
                                                      requires_scaling=False)
    else:
        proposal_provider = None

    od_minibatch_source = ObjectDetectionMinibatchSource(
        cfg["DATA"].TRAIN_MAP_FILE,
        cfg["DATA"].TRAIN_ROI_FILE,
        num_classes=cfg["DATA"].NUM_CLASSES,
        max_annotations_per_image=cfg.INPUT_ROIS_PER_IMAGE,
        pad_width=cfg.IMAGE_WIDTH,
        pad_height=cfg.IMAGE_HEIGHT,
        pad_value=cfg["MODEL"].IMG_PAD_COLOR,
        randomize=True,
        use_flipping=cfg["TRAIN"].USE_FLIPPED,
        max_images=cfg["DATA"].NUM_TRAIN_IMAGES,
        proposal_provider=proposal_provider)

    # define mapping from reader streams to network inputs
    input_map = {
        od_minibatch_source.image_si: image_input,
        od_minibatch_source.roi_si: roi_input,
    }
    if buffered_rpn_proposals is not None:
        input_map[od_minibatch_source.proposals_si] = rpn_rois_input
    else:
        input_map[od_minibatch_source.dims_si] = dims_input

    progress_printer = [
        ProgressPrinter(tag='Training',
                        num_epochs=epochs_to_train,
                        gen_heartbeat=True)
    ]
    tensorboard_logdir = os.path.join(
        os.path.dirname(os.path.abspath(__file__)), r"./TensorBoard")
    tensorboard_writer = None
    if tensorboard_logdir is not None:
        tensorboard_writer = TensorBoardProgressWriter(
            freq=10, log_dir=tensorboard_logdir, model=loss)
        progress_printer.append(tensorboard_writer)

    for epoch in range(epochs_to_train):  # loop over epochs
        sample_count = 0
        while sample_count < cfg[
                "DATA"].NUM_TRAIN_IMAGES:  # loop over minibatches in the epoch
            data = od_minibatch_source.next_minibatch(min(
                cfg.MB_SIZE, cfg["DATA"].NUM_TRAIN_IMAGES - sample_count),
                                                      input_map=input_map)
            output = trainer.train_minibatch(
                data, outputs=[image_input])  # update model with it
            sample_count += trainer.previous_minibatch_sample_count  # count samples processed so far

            #progress_printer.update_with_trainer(trainer, with_metric=True)  # log progress
            #Write output images to tensorboard
            tensorboard_writer.write_image('training', output[1], sample_count)

            if sample_count % 100 == 0:
                print("Processed {} samples".format(sample_count))

        #progress_printer.epoch_summary(with_metric=True)
        trainer.summarize_training_progress()

        if tensorboard_writer:
            for parameter in loss.parameters:
                tensorboard_writer.write_value(parameter.uid + "/mean",
                                               reduce_mean(parameter).eval(),
                                               epoch)
Example #16
0
lr_per_minibatch = learning_rate_schedule(
    [0.01] * 25 + [0.001] * 25 + [0.0001] * 25 + [0.00001] * 25 + [0.000001],
    UnitType.minibatch, epoch_size)
#lr_schedule            = learning_parameter_schedule(lr_per_mb, minibatch_size=minibatch_size, epoch_size=epoch_size)
#mm_schedule            = momentum_schedule(0.9, minibatch_size=minibatch_size)
momentum_time_constant = momentum_as_time_constant_schedule(-minibatch_size /
                                                            np.log(0.9))
l2_reg_weight = 0.0005

# trainer objectS
progress_writers = [ProgressPrinter(tag='Training', num_epochs=max_epochs)]
#progress_writers = [ProgressPrinter(tag='Training', log_to_file=train_log_file, num_epochs=max_epochs, gen_heartbeat=True)]

if cfg.train_log_dir is not None:
    tensorboard_writer = TensorBoardProgressWriter(freq=10,
                                                   log_dir=cfg.train_log_dir,
                                                   model=z)
    progress_writers.append(tensorboard_writer)

learner = momentum_sgd(z.parameters,
                       lr=lr_per_minibatch,
                       momentum=momentum_time_constant,
                       l2_regularization_weight=l2_reg_weight)

######### RESTORE TRAINER IF NEEDED
trainer = Trainer(z, (ce, pe), learner, progress_writers)
# trainer.restore_from_checkpoint(model_temp_file)

# define mapping from reader streams to network inputs
input_map = {
    input_var: reader_train.streams.features,
Example #17
0
def simple_mnist(tensorboard_logdir=None):
    input_dim = 784
    num_output_classes = 10
    num_hidden_layers = 1
    hidden_layers_dim = 200

    # Input variables denoting the features and label data
    feature = input(input_dim, np.float32)
    label = input(num_output_classes, np.float32)

    # Instantiate the feedforward classification model
    scaled_input = element_times(constant(0.00390625), feature)
    z = fully_connected_classifier_net(scaled_input, num_output_classes,
                                       hidden_layers_dim, num_hidden_layers,
                                       relu)

    ce = cross_entropy_with_softmax(z, label)
    pe = classification_error(z, label)

    data_dir = os.path.join(abs_path, "..", "..", "..", "DataSets", "MNIST")

    path = os.path.normpath(os.path.join(data_dir,
                                         "Train-28x28_cntk_text.txt"))
    check_path(path)

    reader_train = create_reader(path, True, input_dim, num_output_classes)

    input_map = {
        feature: reader_train.streams.features,
        label: reader_train.streams.labels
    }

    # Training config
    minibatch_size = 64
    num_samples_per_sweep = 60000
    num_sweeps_to_train_with = 10

    # Instantiate progress writers.
    #training_progress_output_freq = 100
    progress_writers = [
        ProgressPrinter(
            #freq=training_progress_output_freq,
            tag='Training',
            num_epochs=num_sweeps_to_train_with)
    ]

    if tensorboard_logdir is not None:
        progress_writers.append(
            TensorBoardProgressWriter(freq=10,
                                      log_dir=tensorboard_logdir,
                                      model=z))

    # Instantiate the trainer object to drive the model training
    trainer = Trainer(z, (ce, pe), adadelta(z.parameters), progress_writers)

    training_session(trainer=trainer,
                     mb_source=reader_train,
                     mb_size=minibatch_size,
                     var_to_stream=input_map,
                     max_samples=num_samples_per_sweep *
                     num_sweeps_to_train_with,
                     progress_frequency=num_samples_per_sweep).train()

    # Load test data
    path = os.path.normpath(os.path.join(data_dir, "Test-28x28_cntk_text.txt"))
    check_path(path)

    reader_test = create_reader(path, False, input_dim, num_output_classes)

    input_map = {
        feature: reader_test.streams.features,
        label: reader_test.streams.labels
    }

    # Test data for trained model
    test_minibatch_size = 1024
    num_samples = 10000
    num_minibatches_to_test = num_samples / test_minibatch_size
    test_result = 0.0
    for i in range(0, int(num_minibatches_to_test)):
        mb = reader_test.next_minibatch(test_minibatch_size,
                                        input_map=input_map)
        eval_error = trainer.test_minibatch(mb)
        test_result = test_result + eval_error

    # Average of evaluation errors of all test minibatches
    return test_result / num_minibatches_to_test
def init_train_fast_rcnn(image_height,
                         image_width,
                         num_classes,
                         num_rois,
                         mb_size,
                         max_epochs,
                         cntk_lr_per_image,
                         l2_reg_weight,
                         momentum_time_constant,
                         base_path,
                         boSkipTraining=False,
                         debug_output=False,
                         tensorboardLogDir=None):

    #make sure we use GPU for training
    if use_default_device().type() == 0:
        print("WARNING: using CPU for training.")
    else:
        print("Using GPU for training.")

    # Instantiate the Fast R-CNN prediction model
    image_input = input_variable((3, image_height, image_width))
    roi_input = input_variable((num_rois, 4))
    label_input = input_variable((num_rois, num_classes))
    frcn_output, frcn_penultimateLayer = frcn_predictor(
        image_input, roi_input, num_classes, base_path)

    if boSkipTraining:
        print("Using pre-trained DNN without refinement")
        return frcn_penultimateLayer

    # Create the minibatch source and define mapping from reader streams to network inputs
    minibatch_source, epoch_size = create_mb_source("train",
                                                    image_height,
                                                    image_width,
                                                    num_classes,
                                                    num_rois,
                                                    base_path,
                                                    randomize=True)
    input_map = {
        image_input: minibatch_source.streams.features,
        roi_input: minibatch_source.streams.rois,
        label_input: minibatch_source.streams.roiLabels
    }

    # set loss / error functions
    ce = cross_entropy_with_softmax(frcn_output, label_input, axis=1)
    pe = classification_error(frcn_output, label_input, axis=1)
    if debug_output:
        plot(frcn_output, "graph_frcn.png")

    # set the progress printer(s)
    progress_writers = [ProgressPrinter(tag='Training', num_epochs=max_epochs)]
    if tensorboardLogDir != None:
        tensorboard_writer = TensorBoardProgressWriter(
            freq=10, log_dir=tensorboardLogDir, model=frcn_output)
        progress_writers.append(tensorboard_writer)

    # Set learning parameters and instantiate the trainer object
    lr_per_sample = [f / float(num_rois) for f in cntk_lr_per_image]
    lr_schedule = learning_rate_schedule(lr_per_sample, unit=UnitType.sample)
    mm_schedule = momentum_as_time_constant_schedule(momentum_time_constant)
    learner = momentum_sgd(frcn_output.parameters,
                           lr_schedule,
                           mm_schedule,
                           l2_regularization_weight=l2_reg_weight)
    trainer = Trainer(frcn_output, (ce, pe), learner, progress_writers)

    # Get minibatches of images and perform model training
    print("Training Fast R-CNN model for %s epochs." % max_epochs)
    log_number_of_parameters(frcn_output)
    for epoch in range(max_epochs):
        sample_count = 0

        # loop over minibatches in the epoch
        while sample_count < epoch_size:
            data = minibatch_source.next_minibatch(min(
                mb_size, epoch_size - sample_count),
                                                   input_map=input_map)
            if sample_count % 100 == 1:
                print(
                    "Training in progress: epoch {} of {}, sample count {} of {}"
                    .format(epoch, max_epochs, sample_count, epoch_size))
            trainer.train_minibatch(data)
            sample_count += trainer.previous_minibatch_sample_count  # count samples processed so far
        trainer.summarize_training_progress()

        # Log mean of each parameter tensor, so that we can confirm that the parameters change indeed.
        if tensorboardLogDir != None:
            for parameter in frcn_output.parameters:
                tensorboard_writer.write_value(parameter.uid + "/mean",
                                               np.mean(parameter.value), epoch)
                tensorboard_writer.write_value(parameter.uid + "/std",
                                               np.std(parameter.value), epoch)
                tensorboard_writer.write_value(parameter.uid + "/absSum",
                                               np.sum(np.abs(parameter.value)),
                                               epoch)

        if debug_output:
            frcn_output.save_model("frcn_py_%s.model" % (epoch + 1))
    return frcn_output
Example #19
0
    def __init__(self, input_shape, nb_actions,
                 gamma=0.95, explorer=LinearEpsilonAnnealingExplorer(1, 0.1, 100000),
                 learning_rate=0.01, momentum=0.8, minibatch_size=16,
                 memory_size=15000, train_after=100, train_interval=100, target_update_interval=500,
                 monitor=True):
        self.input_shape = input_shape
        self.nb_actions = nb_actions
        self.gamma = gamma

        self._train_after = train_after
        self._train_interval = train_interval
        self._target_update_interval = target_update_interval

        self._explorer = explorer
        self._minibatch_size = minibatch_size
        self._history = History(input_shape)
        self._memory = ReplayMemory(memory_size, input_shape[1:], 4)
        self._num_actions_taken = 0
        self._num_trains = 0

        # Metrics accumulator
        self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

        '''
        # Action Value model (used by agent to interact with the environment)
        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Convolution2D((8, 8), 16, strides=4),
                Convolution2D((4, 4), 32, strides=2),
                Convolution2D((3, 3), 32, strides=1),
                Dense(256, init=he_uniform(scale=0.01)),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))
            ])
        ''' 
        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                Dense(7, init=he_uniform(scale=0.01)),
                Dense(8, init=he_uniform(scale=0.01)),
                #Dense(16, init=he_uniform(scale=0.01)),
                #Dense(32, init=he_uniform(scale=0.01)),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))
            ])
        
        self._action_value_net.update_signature(Tensor[input_shape])

        # Target model used to compute the target Q-values in training, updated
        # less frequently for increased stability.
        self._target_net = self._action_value_net.clone(CloneMethod.freeze)

        # Function computing Q-values targets as part of the computation graph
        @Function
        @Signature(post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def compute_q_targets(post_states, rewards, terminals):
            return element_select(
                terminals,
                rewards,
                gamma * reduce_max(self._target_net(post_states), axis=0) + rewards,
            )

        # Define the loss, using Huber Loss (more robust to outliers)
        @Function
        @Signature(pre_states=Tensor[input_shape], actions=Tensor[nb_actions],
                   post_states=Tensor[input_shape], rewards=Tensor[()], terminals=Tensor[()])
        def criterion(pre_states, actions, post_states, rewards, terminals):
            # Compute the q_targets
            q_targets = compute_q_targets(post_states, rewards, terminals)

            # actions is a 1-hot encoding of the action done by the agent
            q_acted = reduce_sum(self._action_value_net(pre_states) * actions, axis=0)

            # Define training criterion as the Huber Loss function
            return huber_loss(q_targets, q_acted, 1.0)

        # Adam based SGD
        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_schedule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)
        l_sgd = adam(self._action_value_net.parameters, lr_schedule,
                     momentum=m_schedule, variance_momentum=vm_schedule)

        self._metrics_writer = TensorBoardProgressWriter(freq=1, log_dir='metrics', model=criterion) if monitor else None
        self._learner = l_sgd
        self._trainer = Trainer(criterion, (criterion, None), l_sgd, self._metrics_writer)
class DeepQAgent(object):
    """
    Implementation of Deep Q Neural Network agent like in:
        Nature 518. "Human-level control through deep reinforcement learning" (Mnih & al. 2015)
    """
    def __init__(self,
                 input_shape,
                 nb_actions,
                 gamma=0.99,
                 explorer=LinearEpsilonAnnealingExplorer(0.91, 0.1, 910000),
                 fixpolicy=LinearEpsilonAnnealingExplorer(0.5, 0.1, 100000),
                 learning_rate=0.00025,
                 momentum=0.95,
                 minibatch_size=32,
                 memory_size=500000,
                 train_after=10000,
                 train_interval=4,
                 target_update_interval=10000,
                 monitor=True):
        self.input_shape = input_shape
        self.nb_actions = nb_actions
        self.gamma = gamma

        self._train_after = train_after
        self._train_interval = train_interval
        self._target_update_interval = target_update_interval

        self._explorer = explorer
        self._fixpolicy = fixpolicy
        self._minibatch_size = minibatch_size
        self._history = History(input_shape)
        print("input_shape:", input_shape)
        print("input_shape[1:]", input_shape[1:])
        self._memory = ReplayMemory(memory_size, input_shape[1:], 4)
        self._num_actions_taken = 0

        # Metrics accumulator
        self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

        # Action Value model (used by agent to interact with the environment)
        with default_options(activation=relu, init=he_uniform()):
            self._action_value_net = Sequential([
                #Convolution2D((8, 8), 16, strides=4),
                #Convolution2D((4, 4), 32, strides=2),
                #Convolution2D((1, 1), 16, strides=1),
                Dense(25, init=he_uniform(scale=0.01)),
                Dense(nb_actions, activation=None, init=he_uniform(scale=0.01))
            ])
        self._action_value_net.update_signature(Tensor[input_shape])

        # Target model used to compute the target Q-values in training, updated
        # less frequently for increased stability.
        self._target_net = self._action_value_net.clone(CloneMethod.freeze)

        # Function computing Q-values targets as part of the computation graph
        @Function
        @Signature(post_states=Tensor[input_shape],
                   rewards=Tensor[()],
                   terminals=Tensor[()])
        def compute_q_targets(post_states, rewards, terminals):
            return element_select(
                terminals,
                rewards,
                gamma * reduce_max(self._target_net(post_states), axis=0) +
                rewards,
            )

        # Define the loss, using Huber Loss (more robust to outliers)
        @Function
        @Signature(pre_states=Tensor[input_shape],
                   actions=Tensor[nb_actions],
                   post_states=Tensor[input_shape],
                   rewards=Tensor[()],
                   terminals=Tensor[()])
        def criterion(pre_states, actions, post_states, rewards, terminals):
            # Compute the q_targets
            q_targets = compute_q_targets(post_states, rewards, terminals)

            # actions is a 1-hot encoding of the action done by the agent
            q_acted = reduce_sum(self._action_value_net(pre_states) * actions,
                                 axis=0)

            # Define training criterion as the Huber Loss function
            return huber_loss(q_targets, q_acted, 1.0)

        # Adam based SGD
        lr_schedule = learning_rate_schedule(learning_rate, UnitType.minibatch)
        m_schedule = momentum_schedule(momentum)
        vm_schedule = momentum_schedule(0.999)
        l_sgd = adam(self._action_value_net.parameters,
                     lr_schedule,
                     momentum=m_schedule,
                     variance_momentum=vm_schedule)

        self._metrics_writer = TensorBoardProgressWriter(
            freq=1, log_dir='metrics', model=criterion) if monitor else None
        self._learner = l_sgd
        self._trainer = Trainer(criterion, (criterion, None), l_sgd,
                                self._metrics_writer)
        #self._trainer.restore_from_checkpoint("models_heuristic_no_image\model")
    def act(self, state):
        """ This allows the agent to select the next action to perform in regard of the current state of the environment.
        It follows the terminology used in the Nature paper.

        Attributes:
            state (Tensor[input_shape]): The current environment state

        Returns: Int >= 0 : Next action to do
        """
        # Append the state to the short term memory (ie. History)
        self._history.append(state)
        #if True:
        if self._fixpolicy.is_exploring(self._num_actions_taken):
            diff_x = state[3] - state[0]
            diff_y = state[4] - state[1]
            diff_z = state[5] - state[2]
            diff_arr = np.array([diff_x, diff_y, diff_z])
            direction = np.argmax(np.absolute(diff_arr))
            '''
            abs_x = math.fabs(diff_x)
            abs_y = math.fabs(diff_y)
            abs_z = math.fabs(diff_z)
            diff = [diff_x, diff_y, diff_z]
            abs_diff = [abs_x, abs_y, abs_z]
            print(diff, abs_diff)
            m = max(abs_diff)
            direction = diff.index(m)'''
            print(diff_arr)
            if diff_arr[direction] < 0:
                fixaction = direction + 4
            else:
                fixaction = direction + 1

            self._num_actions_taken += 1
            return fixaction

        # If policy requires agent to explore, sample random action
        if self._explorer.is_exploring(self._num_actions_taken):
            action = self._explorer(self.nb_actions)
        else:
            # Use the network to output the best action
            env_with_history = self._history.value
            q_values = self._action_value_net.eval(
                # Append batch axis with only one sample to evaluate
                env_with_history.reshape((1, ) + env_with_history.shape))

            self._episode_q_means.append(np.mean(q_values))
            self._episode_q_stddev.append(np.std(q_values))

            # Return the value maximizing the expected reward
            action = q_values.argmax()

        # Keep track of interval action counter
        self._num_actions_taken += 1
        return action

    def observe(self, old_state, action, reward, done):
        """ This allows the agent to observe the output of doing the action it selected through act() on the old_state

        Attributes:
            old_state (Tensor[input_shape]): Previous environment state
            action (int): Action done by the agent
            reward (float): Reward for doing this action in the old_state environment
            done (bool): Indicate if the action has terminated the environment
        """
        self._episode_rewards.append(reward)

        # If done, reset short term memory (ie. History)
        if done:
            # Plot the metrics through Tensorboard and reset buffers
            if self._metrics_writer is not None:
                self._plot_metrics()
            self._episode_rewards, self._episode_q_means, self._episode_q_stddev = [], [], []

            # Reset the short term memory
            self._history.reset()

        # Append to long term memory
        self._memory.append(old_state, action, reward, done)

    def train(self):
        """ This allows the agent to train itself to better understand the environment dynamics.
        The agent will compute the expected reward for the state(t+1)
        and update the expected reward at step t according to this.

        The target expectation is computed through the Target Network, which is a more stable version
        of the Action Value Network for increasing training stability.

        The Target Network is a frozen copy of the Action Value Network updated as regular intervals.
        """

        agent_step = self._num_actions_taken
        print("agent_step = ", agent_step)
        #time.sleep(1)
        if agent_step >= self._train_after:
            if (agent_step % self._train_interval) == 0:
                pre_states, actions, post_states, rewards, terminals = self._memory.minibatch(
                    self._minibatch_size)

                self._trainer.train_minibatch(
                    self._trainer.loss_function.argument_map(
                        pre_states=pre_states,
                        actions=Value.one_hot(
                            actions.reshape(-1, 1).tolist(), self.nb_actions),
                        post_states=post_states,
                        rewards=rewards,
                        terminals=terminals))

                # Update the Target Network if needed
                if (agent_step % self._target_update_interval) == 0:
                    self._target_net = self._action_value_net.clone(
                        CloneMethod.freeze)
                    filename = "models_heuristic_no_image_less_exploration\model%d" % agent_step
                    print(
                        "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$filename=",
                        filename)
                    self._trainer.save_checkpoint(filename)
                    #time.sleep(100)

    def _plot_metrics(self):
        global landing_count, episode_count
        """Plot current buffers accumulated values to visualize agent learning
        """
        f = open('log__heuristic_no_image_less_exploration2', 'a+')
        f.write('episode:' + str(episode_count) + ': exploration rate= ' +
                str(self._explorer._rate) + ' heuristic fix rate= ' +
                str(self._fixpolicy._rate) + '\n')
        if len(self._episode_q_means) > 0:
            mean_q = np.asscalar(np.mean(self._episode_q_means))
            self._metrics_writer.write_value('Mean Q per ep.', mean_q,
                                             self._num_actions_taken)
            print('Mean Q per ep.', mean_q, self._num_actions_taken)
            f.write('Mean Q per ep. ' + str(mean_q) + ' ' +
                    str(self._num_actions_taken) + '\n')

        if len(self._episode_q_stddev) > 0:
            std_q = np.asscalar(np.mean(self._episode_q_stddev))
            self._metrics_writer.write_value('Mean Std Q per ep.', std_q,
                                             self._num_actions_taken)
            print('Mean Std Q per ep.', std_q, self._num_actions_taken)
            f.write('Mean Std Q per ep. ' + str(std_q) + ' ' +
                    str(self._num_actions_taken) + '\n')

        self._metrics_writer.write_value('Sum rewards per ep.',
                                         sum(self._episode_rewards),
                                         self._num_actions_taken)
        print('Sum rewards per ep.', sum(self._episode_rewards),
              self._num_actions_taken)
        f.write('Sum rewards per ep. ' + str(sum(self._episode_rewards)) +
                ' ' + str(self._num_actions_taken) + '\n')
        if landing_count > 0:
            f.write('****************Success landing**********' +
                    str(landing_count) + '\n')
        landing_count = 0
        episode_count = 0

        f.write('\n')