Exemplo n.º 1
0
def main(save_to, num_epochs):
    mlp = MLP([Tanh(), Softmax()], [784, 100, 10],
              weights_init=IsotropicGaussian(0.01),
              biases_init=Constant(0))
    mlp.initialize()
    x = tensor.matrix('features')
    y = tensor.lmatrix('targets')
    probs = mlp.apply(tensor.flatten(x, outdim=2))
    cost = CategoricalCrossEntropy().apply(y.flatten(), probs)
    error_rate = MisclassificationRate().apply(y.flatten(), probs)

    cg = ComputationGraph([cost])
    W1, W2 = VariableFilter(roles=[WEIGHT])(cg.variables)
    cost = cost + .00005 * (W1**2).sum() + .00005 * (W2**2).sum()
    cost.name = 'final_cost'

    mnist_train = MNIST(("train", ))
    mnist_test = MNIST(("test", ))

    algorithm = GradientDescent(cost=cost,
                                parameters=cg.parameters,
                                step_rule=Scale(learning_rate=0.1))
    extensions = [
        Timing(),
        FinishAfter(after_n_epochs=num_epochs),
        DataStreamMonitoring([cost, error_rate],
                             Flatten(DataStream.default_stream(
                                 mnist_test,
                                 iteration_scheme=SequentialScheme(
                                     mnist_test.num_examples, 500)),
                                     which_sources=('features', )),
                             prefix="test"),
        TrainingDataMonitoring([
            cost, error_rate,
            aggregation.mean(algorithm.total_gradient_norm)
        ],
                               prefix="train",
                               after_epoch=True),
        Checkpoint(save_to),
        Printing()
    ]

    if BLOCKS_EXTRAS_AVAILABLE:
        extensions.append(
            Plot('MNIST example',
                 channels=[[
                     'test_final_cost',
                     'test_misclassificationrate_apply_error_rate'
                 ], ['train_total_gradient_norm']]))

    main_loop = MainLoop(algorithm,
                         Flatten(DataStream.default_stream(
                             mnist_train,
                             iteration_scheme=SequentialScheme(
                                 mnist_train.num_examples, 50)),
                                 which_sources=('features', )),
                         model=Model(cost),
                         extensions=extensions)

    main_loop.run()
Exemplo n.º 2
0
def setup_mainloop(extension):
    """Set up a simple main loop for progress bar tests.

    Create a MainLoop, register the given extension, supply it with a
    DataStream and a minimal model/cost to optimize.

    """
    # Since progressbar2 3.6.0, the `maxval` kwarg has been replaced by
    # `max_value`, which has a default value of 100. If we're still using
    # `maxval` by accident, this test should fail complaining that
    # the progress bar has received a value out of range.
    features = [numpy.array(f, dtype=theano.config.floatX)
                for f in [[1, 2]] * 101]
    dataset = IterableDataset(dict(features=features))

    W = shared_floatx([0, 0], name='W')
    x = tensor.vector('features')
    cost = tensor.sum((x-W)**2)
    cost.name = "cost"

    algorithm = GradientDescent(cost=cost, parameters=[W],
                                step_rule=Scale(1e-3))

    main_loop = MainLoop(
        model=None, data_stream=dataset.get_example_stream(),
        algorithm=algorithm,
        extensions=[
            FinishAfter(after_n_epochs=1),
            extension])

    return main_loop
Exemplo n.º 3
0
def main(save_to, num_batches, continue_=False):
    mlp = MLP([Tanh(), Identity()], [1, 10, 1],
              weights_init=IsotropicGaussian(0.01),
              biases_init=Constant(0),
              seed=1)
    mlp.initialize()
    x = tensor.vector('numbers')
    y = tensor.vector('roots')
    cost = SquaredError().apply(y[:, None], mlp.apply(x[:, None]))
    cost.name = "cost"

    main_loop = MainLoop(
        GradientDescent(cost=cost,
                        params=ComputationGraph(cost).parameters,
                        step_rule=Scale(learning_rate=0.001)),
        get_data_stream(range(100)),
        model=Model(cost),
        extensions=([LoadFromDump(save_to)] if continue_ else []) + [
            Timing(),
            FinishAfter(after_n_batches=num_batches),
            DataStreamMonitoring(
                [cost], get_data_stream(range(100, 200)), prefix="test"),
            TrainingDataMonitoring([cost], after_epoch=True),
            Dump(save_to),
            Printing()
        ])
    main_loop.run()
    return main_loop
Exemplo n.º 4
0
def setup_mainloop(extension):
    """Set up a simple main loop for progress bar tests.

    Create a MainLoop, register the given extension, supply it with a
    DataStream and a minimal model/cost to optimize.

    """
    features = [
        numpy.array(f, dtype=theano.config.floatX)
        for f in [[1, 2], [3, 4], [5, 6]]
    ]
    dataset = IterableDataset(dict(features=features))

    W = shared_floatx([0, 0], name='W')
    x = tensor.vector('features')
    cost = tensor.sum((x - W)**2)
    cost.name = "cost"

    algorithm = GradientDescent(cost=cost, params=[W], step_rule=Scale(1e-3))

    main_loop = MainLoop(model=None,
                         data_stream=dataset.get_example_stream(),
                         algorithm=algorithm,
                         extensions=[FinishAfter(after_n_epochs=1), extension])

    return main_loop
Exemplo n.º 5
0
def learning_algorithm(args):
    name = args.algorithm
    learning_rate = float(args.learning_rate)
    momentum = args.momentum
    clipping_threshold = args.clipping
    clipping = StepClipping(threshold=np.cast[floatX](clipping_threshold))
    if name == 'adam':
        adam = Adam(learning_rate=learning_rate)
        step_rule = CompositeRule([adam, clipping])
        learning_rate = adam.learning_rate
    elif name == 'rms_prop':
        rms_prop = RMSProp(learning_rate=learning_rate)
        step_rule = CompositeRule([clipping, rms_prop])
        learning_rate = rms_prop.learning_rate
    elif name == 'momentum':
        sgd_momentum = Momentum(learning_rate=learning_rate, momentum=momentum)
        step_rule = CompositeRule([clipping, sgd_momentum])
        learning_rate = sgd_momentum.learning_rate
    elif name == 'sgd':
        sgd = Scale(learning_rate=learning_rate)
        step_rule = CompositeRule([clipping, sgd])
        learning_rate = sgd.learning_rate
    else:
        raise NotImplementedError
    return step_rule, learning_rate
Exemplo n.º 6
0
def test_shared_variable_modifier_two_params():
    weights = numpy.array([-1, 1], dtype=floatX)
    features = [numpy.array(f, dtype=floatX) for f in [[1, 2], [3, 4], [5, 6]]]
    targets = [(weights * f).sum() for f in features]
    n_batches = 3
    dataset = ContainerDataset(dict(features=features, targets=targets))

    x = tensor.vector('features')
    y = tensor.scalar('targets')
    W = shared_floatx([0, 0], name='W')
    cost = ((x * W).sum() - y)**2
    cost.name = 'cost'

    step_rule = Scale(0.001)
    sgd = GradientDescent(cost=cost, params=[W], step_rule=step_rule)
    modifier = SharedVariableModifier(
        step_rule.learning_rate, lambda _, val: numpy.cast[floatX](val * 0.2))
    main_loop = MainLoop(model=None,
                         data_stream=dataset.get_default_stream(),
                         algorithm=sgd,
                         extensions=[FinishAfter(after_n_epochs=1), modifier])

    main_loop.run()

    new_value = step_rule.learning_rate.get_value()
    assert_allclose(new_value, 0.001 * 0.2**n_batches, atol=1e-5)
Exemplo n.º 7
0
def test_shared_variable_modifier():
    weights = numpy.array([-1, 1], dtype=theano.config.floatX)
    features = [numpy.array(f, dtype=theano.config.floatX)
                for f in [[1, 2], [3, 4], [5, 6]]]
    targets = [(weights * f).sum() for f in features]
    n_batches = 3
    dataset = IterableDataset(dict(features=features, targets=targets))

    x = tensor.vector('features')
    y = tensor.scalar('targets')
    W = shared_floatx([0, 0], name='W')
    cost = ((x * W).sum() - y) ** 2
    cost.name = 'cost'

    step_rule = Scale(0.001)
    sgd = GradientDescent(cost=cost, parameters=[W],
                          step_rule=step_rule)
    main_loop = MainLoop(
        model=None, data_stream=dataset.get_example_stream(),
        algorithm=sgd,
        extensions=[
            FinishAfter(after_n_epochs=1),
            SharedVariableModifier(
                step_rule.learning_rate,
                lambda n: numpy.cast[theano.config.floatX](10. / n)
            )])

    main_loop.run()

    assert_allclose(step_rule.learning_rate.get_value(),
                    numpy.cast[theano.config.floatX](10. / n_batches))
Exemplo n.º 8
0
def setup_mainloop(extensions):
    """Create a MainLoop, register the given extension, supply it with a
        DataStream and a minimal model/cost to optimize.
    """
    features = [numpy.array(f, dtype=floatX) for f in [[1, 2], [3, 4], [5, 6]]]
    dataset = IterableDataset(dict(features=features))
    datastream = DataStream(dataset)

    W = shared_floatx([0, 0], name='W')
    add_role(W, PARAMETER)
    x = tensor.vector('features')
    cost = tensor.sum((x - W)**2)
    cost.name = "cost"

    algorithm = GradientDescent(cost=cost,
                                parameters=[W],
                                step_rule=Scale(1e-3))

    main_loop = MainLoop(model=Model(cost),
                         data_stream=datastream,
                         algorithm=algorithm,
                         extensions=[
                             FinishAfter(after_n_epochs=1),
                         ] + extensions)

    return main_loop
Exemplo n.º 9
0
def test_training_data_monitoring():
    weights = numpy.array([-1, 1], dtype=theano.config.floatX)
    features = [
        numpy.array(f, dtype=theano.config.floatX)
        for f in [[1, 2], [3, 4], [5, 6]]
    ]
    targets = [(weights * f).sum() for f in features]
    n_batches = 3
    dataset = IterableDataset(dict(features=features, targets=targets))

    x = tensor.vector('features')
    y = tensor.scalar('targets')
    W = shared_floatx([0, 0], name='W')
    V = shared_floatx(7, name='V')
    W_sum = named_copy(W.sum(), 'W_sum')
    cost = ((x * W).sum() - y)**2
    cost.name = 'cost'

    class TrueCostExtension(TrainingExtension):
        def before_batch(self, data):
            self.main_loop.log.current_row['true_cost'] = ((
                (W.get_value() * data["features"]).sum() - data["targets"])**2)

    main_loop = MainLoop(model=None,
                         data_stream=dataset.get_example_stream(),
                         algorithm=GradientDescent(cost=cost,
                                                   parameters=[W],
                                                   step_rule=Scale(0.001)),
                         extensions=[
                             FinishAfter(after_n_epochs=1),
                             TrainingDataMonitoring([W_sum, cost, V],
                                                    prefix="train1",
                                                    after_batch=True),
                             TrainingDataMonitoring(
                                 [aggregation.mean(W_sum), cost],
                                 prefix="train2",
                                 after_epoch=True),
                             TrueCostExtension()
                         ])

    main_loop.run()

    # Check monitoring of a shared varible
    assert_allclose(main_loop.log.current_row['train1_V'], 7.0)

    for i in range(n_batches):
        # The ground truth is written to the log before the batch is
        # processed, where as the extension writes after the batch is
        # processed. This is why the iteration numbers differs here.
        assert_allclose(main_loop.log[i]['true_cost'],
                        main_loop.log[i + 1]['train1_cost'])
    assert_allclose(
        main_loop.log[n_batches]['train2_cost'],
        sum([main_loop.log[i]['true_cost']
             for i in range(n_batches)]) / n_batches)
    assert_allclose(
        main_loop.log[n_batches]['train2_W_sum'],
        sum([
            main_loop.log[i]['train1_W_sum'] for i in range(1, n_batches + 1)
        ]) / n_batches)
Exemplo n.º 10
0
def train_model(cost,
                train_stream,
                valid_stream,
                valid_freq,
                valid_rare,
                load_location=None,
                save_location=None):
    cost.name = 'nll'
    perplexity = 2**(cost / tensor.log(2))
    perplexity.name = 'ppl'

    # Define the model
    model = Model(cost)

    # Load the parameters from a dumped model
    if load_location is not None:
        logger.info('Loading parameters...')
        model.set_param_values(load_parameter_values(load_location))

    cg = ComputationGraph(cost)
    algorithm = GradientDescent(cost=cost,
                                step_rule=Scale(learning_rate=0.01),
                                params=cg.parameters)
    main_loop = MainLoop(
        model=model,
        data_stream=train_stream,
        algorithm=algorithm,
        extensions=[
            DataStreamMonitoring([cost, perplexity],
                                 valid_stream,
                                 prefix='valid_all',
                                 every_n_batches=5000),
            # Overfitting of rare words occurs between 3000 and 4000 iterations
            DataStreamMonitoring([cost, perplexity],
                                 valid_rare,
                                 prefix='valid_rare',
                                 every_n_batches=500),
            DataStreamMonitoring([cost, perplexity],
                                 valid_freq,
                                 prefix='valid_frequent',
                                 every_n_batches=5000),
            Printing(every_n_batches=500)
        ])
    main_loop.run()

    # Save the main loop
    if save_location is not None:
        logger.info('Saving the main loop...')
        dump_manager = MainLoopDumpManager(save_location)
        dump_manager.dump(main_loop)
        logger.info('Saved')
Exemplo n.º 11
0
def run(model_name, port_train, port_valid):

	running_on_laptop = socket.gethostname() == 'yop'

	X = tensor.tensor4('image_features', dtype='float32')
	T = tensor.matrix('targets', dtype='float32')

	image_border_size = (100, 100)

	if running_on_laptop:
		host_plot = 'http://*****:*****@ %s' % (model_name, datetime.datetime.now(), socket.gethostname()), channels=[['loss'], ['error', 'valid_error']], after_epoch=True, server_url=host_plot),
		Printing(),
		Checkpoint('train2')
	]

	main_loop = MainLoop(data_stream=train_stream, algorithm=algorithm,
	                     extensions=extensions)
	main_loop.run()
Exemplo n.º 12
0
    def __init__(self,
                 cost,
                 params,
                 subtensor_params={},
                 step_rule=None,
                 *args,
                 **kwargs):
        full_params = params
        self.subtensor_params = subtensor_params

        # For each LookupTable, we replace it by its subtensors appearing in the graph
        params = [
            param for param in full_params if param not in subtensor_params
        ]
        for _, (_, _, outputs, _) in subtensor_params.iteritems():
            params.extend(outputs)

        super(GradientDescent, self).__init__(cost=cost,
                                              params=params,
                                              **kwargs)
        # self.params contains the list of outputs of the lookup tables

        logger.info("Taking the cost gradient")
        self.gradients = dict(
            equizip(self.params, tensor.grad(self.cost, self.params)))

        # We combine the gradients extracted from the same parameter
        for param, (subparam, canonized_indices, outputs,
                    indices) in subtensor_params.iteritems():
            # This is necessary if we want to compute the l2 norm correctly (e.g. for StepClipping)
            tmp = shared_floatx(param.get_value() * 0.)
            for (output, indice) in zip(outputs, indices):
                tmp = tensor.inc_subtensor(tmp[indice], self.gradients[output])
                del self.gradients[output]
            self.gradients[subparam] = tmp[canonized_indices]

        # We remove the subtensors from the list of parameters
        self.params = full_params

        logger.info("The cost gradient computation graph is built")

        self.step_rule = step_rule if step_rule else Scale()

        self.total_gradient_norm = named_copy(l2_norm(self.gradients.values()),
                                              "total_gradient_norm")
        self.steps, self.step_rule_updates = (self.step_rule.compute_steps(
            self.gradients))
        self.total_step_norm = named_copy(l2_norm(self.steps.values()),
                                          "total_step_norm")
Exemplo n.º 13
0
def test_composite_rule():
    rule = CompositeRule([StepClipping(4), Scale(0.1)])
    gradients = {0: shared_floatx(3.0), 1: shared_floatx(4.0)}
    result, _ = rule.compute_steps(gradients)
    assert_allclose(result[0].eval(), 12 / 50.0)
    assert_allclose(result[1].eval(), 16 / 50.0)

    class RuleWithUpdates(StepRule):
        def __init__(self, updates):
            self.updates = updates

        def compute_steps(self, previous_steps):
            return previous_steps, self.updates

    rule = CompositeRule([RuleWithUpdates([(1, 2)]),
                          RuleWithUpdates([(3, 4)])])
    assert rule.compute_steps(None)[1] == [(1, 2), (3, 4)]
Exemplo n.º 14
0
def test_restrict():
    rule1 = Scale(0.1)
    rule2 = Restrict(rule1, (1, 4))
    rval, _ = rule2.compute_steps(
        OrderedDict((i, shared_floatx(i * i)) for i in range(6)))
    assert_allclose(rval[0].eval(), 0.0)
    assert_allclose(rval[1].eval(), 0.1)
    assert_allclose(rval[2].eval(), 4.0)
    assert_allclose(rval[3].eval(), 9.0)
    assert_allclose(rval[4].eval(), 1.6)
    assert_allclose(rval[5].eval(), 25.0)

    steps, updates = Restrict(DummyUpdatesStepRule(), (1, 4)).compute_steps(
        OrderedDict((i, shared_floatx(i * i)) for i in range(6)))

    assert_allclose(steps[0].eval(), 0.0)
    assert_allclose(steps[1].eval(), 3.0)
    assert_allclose(steps[2].eval(), 4.0)
    assert_allclose(steps[3].eval(), 9.0)
    assert_allclose(steps[4].eval(), 18.0)
    assert_allclose(steps[5].eval(), 25.0)

    assert updates == [(10, 100), (40, 400)]
Exemplo n.º 15
0
def setup_algorithms(cost, cg, method, type="ff"):
    """Setup training algorithm.

    Parameters
    ----------
    cost : expression
        cost expression
    cg : ComputationGraph
        Computation graph
    method : string
        training method: SGD, momentum SGD, AdaGrad, RMSprop
    learning_rate : float
        learning rate for learning method

    Returns
    -------
    algorithm : GradientDescent
        Gradient Descent algorithm based on different optimization method
    """
    if method == "sgd":
        step_rule = Scale(learning_rate=0.01)
    elif method == "momentum":
        step_rule = Momentum(learning_rate=0.01, momentum=0.95)
    elif method == "adagrad":
        step_rule = AdaGrad()
    elif method == "rmsprop":
        step_rule = RMSProp()

    if type == "RNN":
        step_rule = CompositeRule([StepClipping(1.0), step_rule])

    algorithm = GradientDescent(cost=cost,
                                parameters=cg.parameters,
                                step_rule=step_rule)

    return algorithm
Exemplo n.º 16
0
def main():
    feature_maps = [20, 50]
    mlp_hiddens = [50]
    conv_sizes = [5, 5]
    pool_sizes = [3, 3]
    save_to = "DvC.pkl"
    batch_size = 500
    image_size = (32, 32)
    output_size = 2
    learningRate = 0.1
    num_epochs = 10
    num_batches = None
    host_plot = 'http://*****:*****@ %s' %
             ('CNN ', datetime.datetime.now(), socket.gethostname()),
             channels=[['valid_cost', 'valid_error_rate'],
                       ['train_total_gradient_norm']],
             after_epoch=True,
             server_url=host_plot))

    model = Model(cost)

    main_loop = MainLoop(algorithm,
                         stream_data_train,
                         model=model,
                         extensions=extensions)

    main_loop.run()
Exemplo n.º 17
0
def main(save_to, model, train, test, num_epochs, input_size = (150,150), learning_rate=0.01,
batch_size=50, num_batches=None, flatten_stream=False):
    """ 
    save_to : where to save trained model
    model : model given in input must be already initialised (works with convnet and mlp)
    
    input_size : the shape of the reshaped image in input (before flattening is applied if flatten_stream is True)
    
    """
    if flatten_stream :
        x = tensor.matrix('image_features')
    else :
        x = tensor.tensor4('image_features')
    y = tensor.lmatrix('targets')

    #Data augmentation
    #insert data augmentation here 
    
    #Generating stream
    train_stream = DataStream.default_stream(
        train,
        iteration_scheme=ShuffledScheme(train.num_examples, batch_size)
    )

    test_stream = DataStream.default_stream(
        test,
        iteration_scheme=ShuffledScheme(test.num_examples, batch_size)
    )
    
    
    #Reshaping procedure
    #Add a crop option in scikitresize so that the image is not deformed
    
    #Resize to desired square shape
    train_stream = ScikitResize(train_stream, input_size, which_sources=('image_features',))
    test_stream = ScikitResize(test_stream, input_size, which_sources=('image_features',))
    
    #Flattening the stream
    if flatten_stream is True:
        train_stream = Flatten(train_stream, which_sources=('image_features',))
        test_stream = Flatten(test_stream, which_sources=('image_features',))
    
    # Apply input to model
    probs = model.apply(x)
    
    #Defining cost and various indices to watch
    #print(probs)
    #cost = SquaredError().apply(y.flatten(),probs)

    cost = CategoricalCrossEntropy().apply(y.flatten(), probs).copy(name='cost')
    error_rate = MisclassificationRate().apply(y.flatten(), probs).copy(
            name='error_rate')

    #Building Computation Graph
    cg = ComputationGraph([cost, error_rate])

    # Train with simple SGD
    algorithm = GradientDescent(
        cost=cost, parameters=cg.parameters,
        step_rule=Scale(learning_rate=learning_rate))
    
    #Defining extensions
    extensions = [Timing(),
                  FinishAfter(after_n_epochs=num_epochs,
                              after_n_batches=num_batches),
                  TrainingDataMonitoring([cost, error_rate,aggregation.mean(algorithm.total_gradient_norm)], prefix="train", every_n_batches=5),
                  DataStreamMonitoring([cost, error_rate],test_stream,prefix="test", every_n_batches=25),
                  Checkpoint(save_to),
                  ProgressBar(),
                  Printing(every_n_batches=5)]

    # `Timing` extension reports time for reading data, aggregating a batch
    # and monitoring;
    # `ProgressBar` displays a nice progress bar during training.


    model = Model(cost)

    main_loop = MainLoop(
        algorithm,
        train_stream,
        model=model,
        extensions=extensions)

    main_loop.run()
Exemplo n.º 18
0
def main(save_to, num_epochs,
         weight_decay=0.0001, noise_pressure=0, subset=None, num_batches=None,
         batch_size=None, histogram=None, resume=False):
    output_size = 10

    prior_noise_level = -10
    noise_step_rule = Scale(1e-6)
    noise_rate = theano.shared(numpy.asarray(1e-5, dtype=theano.config.floatX))
    convnet = create_res_net(out_noise=True, tied_noise=True, tied_sigma=True,
            noise_rate=noise_rate,
            prior_noise_level=prior_noise_level)

    x = tensor.tensor4('features')
    y = tensor.lmatrix('targets')

    # Normalize input and apply the convnet
    test_probs = convnet.apply(x)
    test_cost = (CategoricalCrossEntropy().apply(y.flatten(), test_probs)
            .copy(name='cost'))
    test_error_rate = (MisclassificationRate().apply(y.flatten(), test_probs)
                  .copy(name='error_rate'))
    test_confusion = (ConfusionMatrix().apply(y.flatten(), test_probs)
                  .copy(name='confusion'))
    test_confusion.tag.aggregation_scheme = Sum(test_confusion)

    test_cg = ComputationGraph([test_cost, test_error_rate])

    # Apply dropout to all layer outputs except final softmax
    # dropout_vars = VariableFilter(
    #         roles=[OUTPUT], bricks=[Convolutional],
    #         theano_name_regex="^conv_[25]_apply_output$")(test_cg.variables)
    # drop_cg = apply_dropout(test_cg, dropout_vars, 0.5)

    # Apply 0.2 dropout to the pre-averaging layer
    # dropout_vars_2 = VariableFilter(
    #         roles=[OUTPUT], bricks=[Convolutional],
    #         theano_name_regex="^conv_8_apply_output$")(test_cg.variables)
    # train_cg = apply_dropout(test_cg, dropout_vars_2, 0.2)

    # Apply 0.2 dropout to the input, as in the paper
    # train_cg = apply_dropout(test_cg, [x], 0.2)
    # train_cg = drop_cg
    # train_cg = apply_batch_normalization(test_cg)

    # train_cost, train_error_rate, train_components = train_cg.outputs

    with batch_normalization(convnet):
        with training_noise(convnet):
            train_probs = convnet.apply(x)
    train_cost = (CategoricalCrossEntropy().apply(y.flatten(), train_probs)
                .copy(name='cost'))
    train_components = (ComponentwiseCrossEntropy().apply(y.flatten(),
                train_probs).copy(name='components'))
    train_error_rate = (MisclassificationRate().apply(y.flatten(),
                train_probs).copy(name='error_rate'))
    train_cg = ComputationGraph([train_cost,
                train_error_rate, train_components])
    population_updates = get_batch_normalization_updates(train_cg)
    bn_alpha = 0.9
    extra_updates = [(p, p * bn_alpha + m * (1 - bn_alpha))
                for p, m in population_updates]

    # for annealing
    nit_penalty = theano.shared(numpy.asarray(noise_pressure, dtype=theano.config.floatX))
    nit_penalty.name = 'nit_penalty'

    # Compute noise rates for training graph
    train_logsigma = VariableFilter(roles=[LOG_SIGMA])(train_cg.variables)
    train_mean_log_sigma = tensor.concatenate([n.flatten() for n in train_logsigma]).mean()
    train_mean_log_sigma.name = 'mean_log_sigma'
    train_nits = VariableFilter(roles=[NITS])(train_cg.auxiliary_variables)
    train_nit_rate = tensor.concatenate([n.flatten() for n in train_nits]).mean()
    train_nit_rate.name = 'nit_rate'
    train_nit_regularization = nit_penalty * train_nit_rate
    train_nit_regularization.name = 'nit_regularization'

    # Apply regularization to the cost
    trainable_parameters = VariableFilter(roles=[WEIGHT, BIAS])(
            train_cg.parameters)
    mask_parameters = [p for p in trainable_parameters
            if get_brick(p).name == 'mask']
    noise_parameters = VariableFilter(roles=[NOISE])(train_cg.parameters)
    biases = VariableFilter(roles=[BIAS])(train_cg.parameters)
    weights = VariableFilter(roles=[WEIGHT])(train_cg.variables)
    nonmask_weights = [p for p in weights if get_brick(p).name != 'mask']
    l2_norm = sum([(W ** 2).sum() for W in nonmask_weights])
    l2_norm.name = 'l2_norm'
    l2_regularization = weight_decay * l2_norm
    l2_regularization.name = 'l2_regularization'

    # testversion
    test_cost = test_cost + l2_regularization
    test_cost.name = 'cost_with_regularization'

    # Training version of cost
    train_cost_without_regularization = train_cost
    train_cost_without_regularization.name = 'cost_without_regularization'
    train_cost = train_cost + l2_regularization + train_nit_regularization
    train_cost.name = 'cost_with_regularization'

    cifar10_train = CIFAR10(("train",))
    cifar10_train_stream = RandomPadCropFlip(
        NormalizeBatchLevels(DataStream.default_stream(
            cifar10_train, iteration_scheme=ShuffledScheme(
                cifar10_train.num_examples, batch_size)),
        which_sources=('features',)),
        (32, 32), pad=4, which_sources=('features',))

    test_batch_size = 128
    cifar10_test = CIFAR10(("test",))
    cifar10_test_stream = NormalizeBatchLevels(DataStream.default_stream(
        cifar10_test,
        iteration_scheme=ShuffledScheme(
            cifar10_test.num_examples, test_batch_size)),
        which_sources=('features',))

    momentum = Momentum(0.01, 0.9)

    # Create a step rule that doubles the learning rate of biases, like Caffe.
    # scale_bias = Restrict(Scale(2), biases)
    # step_rule = CompositeRule([scale_bias, momentum])

    # Create a step rule that reduces the learning rate of noise
    scale_mask = Restrict(noise_step_rule, mask_parameters)
    step_rule = CompositeRule([scale_mask, momentum])

    # from theano.compile.nanguardmode import NanGuardMode

    # Train with simple SGD
    algorithm = GradientDescent(
        cost=train_cost, parameters=trainable_parameters,
        step_rule=step_rule)
    algorithm.add_updates(extra_updates)

    #,
    #    theano_func_kwargs={
    #        'mode': NanGuardMode(
    #            nan_is_error=True, inf_is_error=True, big_is_error=True)})

    exp_name = save_to.replace('.%d', '')

    # `Timing` extension reports time for reading data, aggregating a batch
    # and monitoring;
    # `ProgressBar` displays a nice progress bar during training.
    extensions = [Timing(),
                  FinishAfter(after_n_epochs=num_epochs,
                              after_n_batches=num_batches),
                  EpochSchedule(momentum.learning_rate, [
                      (0, 0.01),     # Warm up with 0.01 learning rate
                      (50, 0.1),     # Then go back to 0.1
                      (100, 0.01),
                      (150, 0.001)
                      # (83, 0.01),  # Follow the schedule in the paper
                      # (125, 0.001)
                  ]),
                  EpochSchedule(noise_step_rule.learning_rate, [
                      (0, 1e-2),
                      (2, 1e-1),
                      (4, 1)
                      # (0, 1e-6),
                      # (2, 1e-5),
                      # (4, 1e-4)
                  ]),
                  EpochSchedule(noise_rate, [
                      (0, 1e-2),
                      (2, 1e-1),
                      (4, 1)
                      # (0, 1e-6),
                      # (2, 1e-5),
                      # (4, 1e-4),
                      # (6, 3e-4),
                      # (8, 1e-3), # Causes nit rate to jump
                      # (10, 3e-3),
                      # (12, 1e-2),
                      # (15, 3e-2),
                      # (19, 1e-1),
                      # (24, 3e-1),
                      # (30, 1)
                  ]),
                  NoiseExtension(
                      noise_parameters=noise_parameters),
                  NoisyDataStreamMonitoring(
                      [test_cost, test_error_rate, test_confusion],
                      cifar10_test_stream,
                      noise_parameters=noise_parameters,
                      prefix="test"),
                  TrainingDataMonitoring(
                      [train_cost, train_error_rate, train_nit_rate,
                       train_cost_without_regularization,
                       l2_regularization,
                       train_nit_regularization,
                       momentum.learning_rate,
                       train_mean_log_sigma,
                       aggregation.mean(algorithm.total_gradient_norm)],
                      prefix="train",
                      every_n_batches=17),
                      # after_epoch=True),
                  Plot('Training performance for ' + exp_name,
                      channels=[
                          ['train_cost_with_regularization',
                           'train_cost_without_regularization',
                           'train_nit_regularization',
                           'train_l2_regularization'],
                          ['train_error_rate'],
                          ['train_total_gradient_norm'],
                          ['train_mean_log_sigma'],
                      ],
                      every_n_batches=17),
                  Plot('Test performance for ' + exp_name,
                      channels=[[
                          'train_error_rate',
                          'test_error_rate',
                          ]],
                      after_epoch=True),
                  EpochCheckpoint(save_to, use_cpickle=True, after_epoch=True),
                  ProgressBar(),
                  Printing()]

    if histogram:
        attribution = AttributionExtension(
            components=train_components,
            parameters=cg.parameters,
            components_size=output_size,
            after_batch=True)
        extensions.insert(0, attribution)

    if resume:
        extensions.append(Load(exp_name, True, True))

    model = Model(train_cost)

    main_loop = MainLoop(
        algorithm,
        cifar10_train_stream,
        model=model,
        extensions=extensions)

    main_loop.run()

    if histogram:
        save_attributions(attribution, filename=histogram)

    with open('execution-log.json', 'w') as outfile:
        json.dump(main_loop.log, outfile, cls=NumpyEncoder)
Exemplo n.º 19
0
if mode is "data_server":
    data_train_stream = ServerDataStream(('image_features','targets'), False, port=5560)
    data_valid_stream = ServerDataStream(('image_features','targets'), False, port=5561)


### Setting up the model
probs = top_mlp.apply(conv_out)

cost = CategoricalCrossEntropy().apply(y.flatten(), probs).copy(name='cost')
error = MisclassificationRate().apply(y.flatten(), probs)
error_rate = error.copy(name='error_rate')
error_rate2 = error.copy(name='error_rate2')
cg = ComputationGraph([cost, error_rate])

### Gradient Descent
algorithm = GradientDescent(cost=cost, parameters=cg.parameters, step_rule=Scale(learning_rate=learning_rate))

extensions = [Timing(),
              FinishAfter(after_n_epochs=num_epochs),
              DataStreamMonitoring(
                  [cost, error_rate, error_rate2],
                  data_valid_stream,
                  prefix="valid"),
              TrainingDataMonitoring(
                  [cost, error_rate,
                   aggregation.mean(algorithm.total_gradient_norm)],
                  prefix="train",
                  after_epoch=True),
             Checkpoint(save_to),
              ProgressBar(),
              Printing()]
Exemplo n.º 20
0
print("Cost graph is built", file=sys.stderr)

model = Model(cost)
parameters = model.get_parameter_dict()

for brick in model.get_top_bricks():  #{
    brick.initialize()
#}

cg = ComputationGraph(cost)

algo = GradientDescent(cost=cost,
                       parameters=cg.parameters,
                       step_rule=CompositeRule(
                           [StepClipping(10.0),
                            Scale(0.01)]))
#algo = RMSProp(learning_rate=1.0, decay_rate=0.9)

max_length = chars.shape[0].copy(name="max_length")
observables = [
    batch_size, max_length, algo.total_step_norm, algo.total_gradient_norm,
    cost
]

# Construct the main loop and start training!
average_monitoring = TrainingDataMonitoring(observables,
                                            prefix="average",
                                            every_n_batches=10)

checkpoint_after = n_epochs / 5
#checkpoint_after=100;
Exemplo n.º 21
0
 def __init__(self, learning_rate=1.0, momentum=0.):
     scale = Scale(learning_rate=learning_rate)
     basic_nesterov_momentum = BasicNesterovMomentum(momentum=momentum)
     self.learning_rate = scale.learning_rate
     self.momentum = basic_nesterov_momentum.momentum
     self.components = [scale, basic_nesterov_momentum]
Exemplo n.º 22
0
def train(algorithm, learning_rate, clipping, momentum, layer_size, epochs,
          test_cost, experiment_path, initialization, init_width, weight_noise,
          z_prob, z_prob_states, z_prob_cells, drop_prob_igates,
          ogates_zoneout, batch_size, stoch_depth, share_mask, gaussian_drop,
          rnn_type, num_layers, norm_cost_coeff, penalty, testing, seq_len,
          decrease_lr_after_epoch, lr_decay, **kwargs):

    print '.. PTB experiment'
    print '.. arguments:', ' '.join(sys.argv)
    t0 = time.time()

    ###########################################
    #
    # LOAD DATA
    #
    ###########################################

    def onehot(x, numclasses=None):
        """ Convert integer encoding for class-labels (starting with 0 !)
            to one-hot encoding.
            The output is an array whose shape is the shape of the input array
            plus an extra dimension, containing the 'one-hot'-encoded labels.
        """
        if x.shape == ():
            x = x[None]
        if numclasses is None:
            numclasses = x.max() + 1
        result = numpy.zeros(list(x.shape) + [numclasses], dtype="int")
        z = numpy.zeros(x.shape, dtype="int")
        for c in range(numclasses):
            z *= 0
            z[numpy.where(x == c)] = 1
            result[..., c] += z
        return result.astype(theano.config.floatX)

    alphabetsize = 10000
    data = np.load('penntree_char_and_word.npz')
    trainset = data['train_words']
    validset = data['valid_words']
    testset = data['test_words']

    if testing:
        trainset = trainset[:3000]
        validset = validset[:3000]

    if share_mask:
        if not z_prob:
            raise ValueError('z_prob must be provided when using share_mask')
        if z_prob_cells or z_prob_states:
            raise ValueError(
                'z_prob_states and z_prob_cells must not be provided when using share_mask (use z_prob instead)'
            )
        z_prob_cells = z_prob
        # we don't want to actually use these masks, so this is to debug
        z_prob_states = None
    else:
        if z_prob:
            raise ValueError('z_prob is only used with share_mask')
        z_prob_cells = z_prob_cells or '1'
        z_prob_states = z_prob_states or '1'


#    rng = np.random.RandomState(seed)

###########################################
#
# MAKE STREAMS
#
###########################################

    def prep_dataset(dataset):
        dataset = dataset[:(len(dataset) - (len(dataset) %
                                            (seq_len * batch_size)))]
        dataset = dataset.reshape(batch_size, -1, seq_len).transpose((1, 0, 2))

        stream = DataStream(
            IndexableDataset(indexables=OrderedDict([('data', dataset)])),
            iteration_scheme=SequentialExampleScheme(dataset.shape[0]))
        stream = Transpose(stream, [(1, 0)])
        stream = SampleDropsNPWord(stream, z_prob_states, z_prob_cells,
                                   drop_prob_igates, layer_size, num_layers,
                                   False, stoch_depth, share_mask,
                                   gaussian_drop, alphabetsize)
        stream.sources = ('data', ) * 3 + stream.sources + (
            'zoneouts_states', 'zoneouts_cells', 'zoneouts_igates')
        return (stream, )

    train_stream, = prep_dataset(trainset)
    valid_stream, = prep_dataset(validset)
    test_stream, = prep_dataset(testset)

    ####################

    data = train_stream.get_epoch_iterator(as_dict=True).next()

    ####################

    ###########################################
    #
    # BUILD MODEL
    #
    ###########################################
    print '.. building model'

    x = T.tensor3('data')
    y = x
    zoneouts_states = T.tensor3('zoneouts_states')
    zoneouts_cells = T.tensor3('zoneouts_cells')
    zoneouts_igates = T.tensor3('zoneouts_igates')

    x.tag.test_value = data['data']
    zoneouts_states.tag.test_value = data['zoneouts_states']
    zoneouts_cells.tag.test_value = data['zoneouts_cells']
    zoneouts_igates.tag.test_value = data['zoneouts_igates']

    if init_width and not initialization == 'uniform':
        raise ValueError('Width is only for uniform init, whassup?')

    if initialization == 'glorot':
        weights_init = NormalizedInitialization()
    elif initialization == 'uniform':
        weights_init = Uniform(width=init_width)
    elif initialization == 'ortho':
        weights_init = OrthogonalInitialization()
    else:
        raise ValueError('No such initialization')

    if rnn_type.lower() == 'lstm':
        in_to_hids = [
            Linear(layer_size if l > 0 else alphabetsize,
                   layer_size * 4,
                   name='in_to_hid%d' % l,
                   weights_init=weights_init,
                   biases_init=Constant(0.0)) for l in range(num_layers)
        ]
        recurrent_layers = [
            DropLSTM(dim=layer_size,
                     weights_init=weights_init,
                     activation=Tanh(),
                     model_type=6,
                     name='rnn%d' % l,
                     ogates_zoneout=ogates_zoneout) for l in range(num_layers)
        ]
    elif rnn_type.lower() == 'gru':
        in_to_hids = [
            Linear(layer_size if l > 0 else alphabetsize,
                   layer_size * 3,
                   name='in_to_hid%d' % l,
                   weights_init=weights_init,
                   biases_init=Constant(0.0)) for l in range(num_layers)
        ]
        recurrent_layers = [
            DropGRU(dim=layer_size,
                    weights_init=weights_init,
                    activation=Tanh(),
                    name='rnn%d' % l) for l in range(num_layers)
        ]
    elif rnn_type.lower() == 'srnn':  # FIXME!!! make ReLU
        in_to_hids = [
            Linear(layer_size if l > 0 else alphabetsize,
                   layer_size,
                   name='in_to_hid%d' % l,
                   weights_init=weights_init,
                   biases_init=Constant(0.0)) for l in range(num_layers)
        ]
        recurrent_layers = [
            DropSimpleRecurrent(dim=layer_size,
                                weights_init=weights_init,
                                activation=Rectifier(),
                                name='rnn%d' % l) for l in range(num_layers)
        ]
    else:
        raise NotImplementedError

    hid_to_out = Linear(layer_size,
                        alphabetsize,
                        name='hid_to_out',
                        weights_init=weights_init,
                        biases_init=Constant(0.0))

    for layer in in_to_hids:
        layer.initialize()
    for layer in recurrent_layers:
        layer.initialize()
    hid_to_out.initialize()

    layer_input = x  #in_to_hid.apply(x)

    init_updates = OrderedDict()
    for l, (in_to_hid, layer) in enumerate(zip(in_to_hids, recurrent_layers)):
        rnn_embedding = in_to_hid.apply(layer_input)
        if rnn_type.lower() == 'lstm':
            states_init = theano.shared(
                np.zeros((batch_size, layer_size), dtype=floatX))
            cells_init = theano.shared(
                np.zeros((batch_size, layer_size), dtype=floatX))
            states_init.name, cells_init.name = "states_init", "cells_init"
            states, cells = layer.apply(
                rnn_embedding,
                zoneouts_states[:, :, l * layer_size:(l + 1) * layer_size],
                zoneouts_cells[:, :, l * layer_size:(l + 1) * layer_size],
                zoneouts_igates[:, :, l * layer_size:(l + 1) * layer_size],
                states_init, cells_init)
            init_updates.update([(states_init, states[-1]),
                                 (cells_init, cells[-1])])
        elif rnn_type.lower() in ['gru', 'srnn']:
            # untested!
            states_init = theano.shared(
                np.zeros((batch_size, layer_size), dtype=floatX))
            states_init.name = "states_init"
            states = layer.apply(rnn_embedding, zoneouts_states,
                                 zoneouts_igates, states_init)
            init_updates.update([(states_init, states[-1])])
        else:
            raise NotImplementedError
        layer_input = states

    y_hat_pre_softmax = hid_to_out.apply(T.join(0, [states_init], states[:-1]))
    shape_ = y_hat_pre_softmax.shape
    y_hat = Softmax().apply(y_hat_pre_softmax.reshape((-1, alphabetsize)))

    ####################

    ###########################################
    #
    # SET UP COSTS AND MONITORS
    #
    ###########################################

    cost = CategoricalCrossEntropy().apply(y.reshape((-1, alphabetsize)),
                                           y_hat).copy('cost')

    bpc = (cost / np.log(2.0)).copy(name='bpr')
    perp = T.exp(cost).copy(name='perp')

    cost_train = cost.copy(name='train_cost')
    cg_train = ComputationGraph([cost_train])

    ###########################################
    #
    # NORM STABILIZER
    #
    ###########################################
    norm_cost = 0.

    def _magnitude(x, axis=-1):
        return T.sqrt(
            T.maximum(T.sqr(x).sum(axis=axis),
                      numpy.finfo(x.dtype).tiny))

    if penalty == 'cells':
        assert VariableFilter(roles=[MEMORY_CELL])(cg_train.variables)
        for cell in VariableFilter(roles=[MEMORY_CELL])(cg_train.variables):
            norms = _magnitude(cell)
            norm_cost += T.mean(
                T.sum((norms[1:] - norms[:-1])**2, axis=0) / (seq_len - 1))
    elif penalty == 'hids':
        for l in range(num_layers):
            assert 'rnn%d_apply_states' % l in [
                o.name
                for o in VariableFilter(roles=[OUTPUT])(cg_train.variables)
            ]
        for output in VariableFilter(roles=[OUTPUT])(cg_train.variables):
            for l in range(num_layers):
                if output.name == 'rnn%d_apply_states' % l:
                    norms = _magnitude(output)
                    norm_cost += T.mean(
                        T.sum((norms[1:] - norms[:-1])**2, axis=0) /
                        (seq_len - 1))

    norm_cost.name = 'norm_cost'
    #cost_valid = cost_train
    cost_train += norm_cost_coeff * norm_cost
    cost_train = cost_train.copy(
        'cost_train')  #should this be cost_train.outputs[0]? no.

    cg_train = ComputationGraph([cost_train])

    ###########################################
    #
    # WEIGHT NOISE
    #
    ###########################################

    if weight_noise > 0:
        weights = VariableFilter(roles=[WEIGHT])(cg_train.variables)
        cg_train = apply_noise(cg_train, weights, weight_noise)
        cost_train = cg_train.outputs[0].copy(name='cost_train')

    model = Model(cost_train)

    learning_rate = float(learning_rate)
    clipping = StepClipping(threshold=np.cast[floatX](clipping))
    if algorithm == 'adam':
        adam = Adam(learning_rate=learning_rate)
        learning_rate = adam.learning_rate
        step_rule = CompositeRule([adam, clipping])
    elif algorithm == 'rms_prop':
        rms_prop = RMSProp(learning_rate=learning_rate)
        learning_rate = rms_prop.learning_rate
        step_rule = CompositeRule([clipping, rms_prop])
    elif algorithm == 'momentum':
        sgd_momentum = Momentum(learning_rate=learning_rate, momentum=momentum)
        learning_rate = sgd_momentum.learning_rate
        step_rule = CompositeRule([clipping, sgd_momentum])
    elif algorithm == 'sgd':
        sgd = Scale(learning_rate=learning_rate)
        learning_rate = sgd.learning_rate
        step_rule = CompositeRule([clipping, sgd])
    else:
        raise NotImplementedError
    algorithm = GradientDescent(step_rule=step_rule,
                                cost=cost_train,
                                parameters=cg_train.parameters)
    # theano_func_kwargs={"mode": theano.compile.MonitorMode(post_func=detect_nan)})

    algorithm.add_updates(init_updates)

    def cond_number(x):
        _, _, sing_vals = T.nlinalg.svd(x, True, True)
        sing_mags = abs(sing_vals)
        return T.max(sing_mags) / T.min(sing_mags)

    def rms(x):
        return (x * x).mean().sqrt()

    whysplode_cond = []
    whysplode_rms = []
    for i, p in enumerate(init_updates):
        v = p.get_value()
        if p.get_value().shape == 2:
            whysplode_cond.append(
                cond_number(p).copy(
                    'ini%d:%s_cond(%s)' %
                    (i, p.name, "x".join(map(str,
                                             p.get_value().shape)))))
        whysplode_rms.append(
            rms(p).copy('ini%d:%s_rms(%s)' %
                        (i, p.name, "x".join(map(str,
                                                 p.get_value().shape)))))
    for i, p in enumerate(cg_train.parameters):
        v = p.get_value()
        if p.get_value().shape == 2:
            whysplode_cond.append(
                cond_number(p).copy(
                    'ini%d:%s_cond(%s)' %
                    (i, p.name, "x".join(map(str,
                                             p.get_value().shape)))))
        whysplode_rms.append(
            rms(p).copy('ini%d:%s_rms(%s)' %
                        (i, p.name, "x".join(map(str,
                                                 p.get_value().shape)))))

    observed_vars = [
        cost_train, cost, bpc, perp, learning_rate,
        aggregation.mean(
            algorithm.total_gradient_norm).copy("gradient_norm_mean")
    ]  # + whysplode_rms

    parameters = model.get_parameter_dict()
    for name, param in parameters.iteritems():
        observed_vars.append(param.norm(2).copy(name=name + "_norm"))
        observed_vars.append(
            algorithm.gradients[param].norm(2).copy(name=name + "_grad_norm"))

    train_monitor = TrainingDataMonitoring(variables=observed_vars,
                                           prefix="train",
                                           after_epoch=True)

    dev_inits = [p.clone() for p in init_updates]
    cg_dev = ComputationGraph([cost, bpc, perp] +
                              init_updates.values()).replace(
                                  zip(init_updates.keys(), dev_inits))
    dev_cost, dev_bpc, dev_perp = cg_dev.outputs[:3]
    dev_init_updates = OrderedDict(zip(dev_inits, cg_dev.outputs[3:]))

    dev_monitor = DataStreamMonitoring(variables=[dev_cost, dev_bpc, dev_perp],
                                       data_stream=valid_stream,
                                       prefix="dev",
                                       updates=dev_init_updates)

    # noone does this
    if 'load_path' in kwargs:
        with open(kwargs['load_path']) as f:
            loaded = np.load(f)
            model = Model(cost_train)
            params_dicts = model.get_parameter_dict()
            params_names = params_dicts.keys()
            for param_name in params_names:
                param = params_dicts[param_name]
                # '/f_6_.W' --> 'f_6_.W'
                slash_index = param_name.find('/')
                param_name = param_name[slash_index + 1:]
                if param.get_value().shape == loaded[param_name].shape:
                    print 'Found: ' + param_name
                    param.set_value(loaded[param_name])
                else:
                    print 'Not found: ' + param_name

    extensions = []
    extensions.extend(
        [FinishAfter(after_n_epochs=epochs), train_monitor, dev_monitor])
    if test_cost:
        test_inits = [p.clone() for p in init_updates]
        cg_test = ComputationGraph([cost, bpc, perp] +
                                   init_updates.values()).replace(
                                       zip(init_updates.keys(), test_inits))
        test_cost, test_bpc, test_perp = cg_test.outputs[:3]
        test_init_updates = OrderedDict(zip(test_inits, cg_test.outputs[3:]))

        test_monitor = DataStreamMonitoring(
            variables=[test_cost, test_bpc, test_perp],
            data_stream=test_stream,
            prefix="test",
            updates=test_init_updates)
        extensions.extend([test_monitor])

    if not os.path.exists(experiment_path):
        os.makedirs(experiment_path)
    log_path = os.path.join(experiment_path, 'log.txt')
    fh = logging.FileHandler(filename=log_path)
    fh.setLevel(logging.DEBUG)
    logger.addHandler(fh)

    extensions.append(
        SaveParams('dev_cost', model, experiment_path, every_n_epochs=1))
    extensions.append(SaveLog(every_n_epochs=1))
    extensions.append(ProgressBar())
    extensions.append(Printing())

    class RollsExtension(TrainingExtension):
        """ rolls the cell and state activations between epochs so that first batch gets correct initial activations """
        def __init__(self, shvars):
            self.shvars = shvars

        def before_epoch(self):
            for v in self.shvars:
                v.set_value(np.roll(v.get_value(), 1, 0))

    extensions.append(
        RollsExtension(init_updates.keys() + dev_init_updates.keys() +
                       (test_init_updates.keys() if test_cost else [])))

    class LearningRateSchedule(TrainingExtension):
        """ Lets you set a number to divide learning rate by each epoch + when to start doing that """
        def __init__(self):
            self.epoch_number = 0

        def after_epoch(self):
            self.epoch_number += 1
            if self.epoch_number > decrease_lr_after_epoch:
                learning_rate.set_value(learning_rate.get_value() / lr_decay)

    if bool(lr_decay) != bool(decrease_lr_after_epoch):
        raise ValueError(
            'Need to define both lr_decay and decrease_lr_after_epoch')
    if lr_decay and decrease_lr_after_epoch:
        extensions.append(LearningRateSchedule())

    main_loop = MainLoop(model=model,
                         data_stream=train_stream,
                         algorithm=algorithm,
                         extensions=extensions)
    t1 = time.time()
    print "Building time: %f" % (t1 - t0)

    main_loop.run()
    print "Execution time: %f" % (time.time() - t1)
Exemplo n.º 23
0
def run(get_model, model_name):
    train_stream = ServerDataStream(
        ('cases', 'image_features', 'image_targets', 'multiplier'),
        False,
        hwm=10)
    valid_stream = ServerDataStream(
        ('cases', 'image_features', 'image_targets', 'multiplier'),
        False,
        hwm=10,
        port=5558)

    input_var = tensor.tensor4('image_features')
    target_var = tensor.tensor4('image_targets')
    multiply_var = tensor.matrix('multiplier')
    multiply_var = T.addbroadcast(multiply_var, 1)

    test_prediction, prediction, params = get_model(input_var, target_var,
                                                    multiply_var)

    loss = binary_crossentropy(prediction, target_var).mean()

    loss.name = 'loss'

    valid_error = T.neq((test_prediction > 0.5) * 1., target_var).mean()
    valid_error.name = 'error'

    scale = Scale(0.1)
    algorithm = GradientDescent(
        cost=loss,
        parameters=params,
        step_rule=scale,
        #step_rule=Adam(),
        on_unused_sources='ignore')

    host_plot = 'http://localhost:5006'

    extensions = [
        Timing(),
        TrainingDataMonitoring([loss], after_epoch=True),
        DataStreamMonitoring(variables=[loss, valid_error],
                             data_stream=valid_stream,
                             prefix="valid"),
        Plot('%s %s %s' %
             (model_name, datetime.date.today(), time.strftime('%H:%M')),
             channels=[['loss', 'valid_loss'], ['valid_error']],
             after_epoch=True,
             server_url=host_plot),
        Printing(),
        # Checkpoint('train'),
        FinishAfter(after_n_epochs=10)
    ]

    main_loop = MainLoop(data_stream=train_stream,
                         algorithm=algorithm,
                         extensions=extensions)
    cg = ComputationGraph(test_prediction)
    while True:
        main_loop.run()
        scale.learning_rate.set_value(
            numpy.float32(scale.learning_rate.get_value() * 0.7))
        numpy.savez('best_weights.npz',
                    [param.get_value() for param in cg.shared_variables])
Exemplo n.º 24
0
def main(save_to,
         num_epochs,
         feature_maps=None,
         mlp_hiddens=None,
         conv_sizes=None,
         pool_sizes=None,
         batch_size=500):
    if feature_maps is None:
        feature_maps = [20, 50]
    if mlp_hiddens is None:
        mlp_hiddens = [500]
    if conv_sizes is None:
        conv_sizes = [5, 5]
    if pool_sizes is None:
        pool_sizes = [2, 2]
    image_size = (28, 28)
    output_size = 10

    # Use ReLUs everywhere and softmax for the final prediction
    conv_activations = [Rectifier() for _ in feature_maps]
    mlp_activations = [Rectifier() for _ in mlp_hiddens] + [Softmax()]
    convnet = LeNet(conv_activations,
                    1,
                    image_size,
                    filter_sizes=zip(conv_sizes, conv_sizes),
                    feature_maps=feature_maps,
                    pooling_sizes=zip(pool_sizes, pool_sizes),
                    top_mlp_activations=mlp_activations,
                    top_mlp_dims=mlp_hiddens + [output_size],
                    border_mode='full',
                    weights_init=Uniform(width=.2),
                    biases_init=Constant(0))
    # We push initialization config to set different initialization schemes
    # for convolutional layers.
    convnet.push_initialization_config()
    convnet.layers[0].weights_init = Uniform(width=.2)
    convnet.layers[1].weights_init = Uniform(width=.09)
    convnet.top_mlp.linear_transformations[0].weights_init = Uniform(width=.08)
    convnet.top_mlp.linear_transformations[1].weights_init = Uniform(width=.11)
    convnet.initialize()
    logging.info(
        "Input dim: {} {} {}".format(*convnet.children[0].get_dim('input_')))
    for i, layer in enumerate(convnet.layers):
        logging.info("Layer {} dim: {} {} {}".format(i,
                                                     *layer.get_dim('output')))

    x = tensor.tensor4('features')
    y = tensor.lmatrix('targets')

    # Normalize input and apply the convnet
    probs = convnet.apply(x)
    cost = named_copy(CategoricalCrossEntropy().apply(y.flatten(), probs),
                      'cost')
    error_rate = named_copy(MisclassificationRate().apply(y.flatten(), probs),
                            'error_rate')

    cg = ComputationGraph([cost, error_rate])

    mnist_train = MNIST(("train", ))
    mnist_train_stream = DataStream.default_stream(
        mnist_train,
        iteration_scheme=ShuffledScheme(mnist_train.num_examples, batch_size))

    mnist_test = MNIST(("test", ))
    mnist_test_stream = DataStream.default_stream(
        mnist_test,
        iteration_scheme=ShuffledScheme(mnist_test.num_examples, batch_size))

    # Train with simple SGD
    algorithm = GradientDescent(cost=cost,
                                parameters=cg.parameters,
                                step_rule=Scale(learning_rate=0.1))
    # `Timing` extension reports time for reading data, aggregating a batch
    # and monitoring;
    # `ProgressBar` displays a nice progress bar during training.
    extensions = [
        Timing(),
        FinishAfter(after_n_epochs=num_epochs),
        DataStreamMonitoring([cost, error_rate],
                             mnist_test_stream,
                             prefix="test"),
        TrainingDataMonitoring([
            cost, error_rate,
            aggregation.mean(algorithm.total_gradient_norm)
        ],
                               prefix="train",
                               after_epoch=True),
        Checkpoint(save_to),
        ProgressBar(),
        Printing()
    ]

    model = Model(cost)

    main_loop = MainLoop(algorithm,
                         mnist_train_stream,
                         model=model,
                         extensions=extensions)

    main_loop.run()
Exemplo n.º 25
0
    #print(cg.variables)

    print("Created ComputationGraph, parameters:")
    #print(cg.parameters)
    for p in cg.parameters:
        print(str(p), p.dtype, p.shape.tag.test_value)

    print("Created ComputationGraph, inputs:")
    print(cg.inputs)

    algorithm = GradientDescent(
        cost=cost,
        parameters=cg.parameters,
        step_rule=CompositeRule([
            StepClipping(10.0),
            Scale(0.01),
        ]),
    )
    print("Defined Algorithm")

    model = Model(cost)
    print("Defined Model")

    obs_max_length = named_copy(x.shape[0], "obs_max_length")
    observables = [
        cost,
        obs_max_length,
        #min_energy, max_energy,
        #mean_activation,
    ]
Exemplo n.º 26
0
seq_gen.initialize()

# z markov_tutorial
x = tensor.lvector('features')
x = x.reshape((x.shape[0], 1))
cost = aggregation.mean(seq_gen.cost_matrix(x[:, :]).sum(), x.shape[1])
cost.name = "negative log-likelihood"
cost_cg = ComputationGraph(cost)

print VariableFilter(roles=[WEIGHT])(cost_cg.variables)
# theano.printing.pydotprint(cost, outfile="./pics/symbolic_graph_unopt.png", var_with_name_simple=True)

algorithm = GradientDescent(cost=cost,
                            parameters=list(
                                Selector(seq_gen).get_parameters().values()),
                            step_rule=Scale(0.001))

# AUDIOSCOPE OBSERVABLES (some)
observables = []
observables += cost_cg.outputs
observables.append(algorithm.total_step_norm)
observables.append(algorithm.total_gradient_norm)

print observables

# AUDIOSCOPE EXTENSIONS
extensions = []
extensions.append(Timing(after_batch=True))
extensions.append(TrainingDataMonitoring(list(observables), after_batch=True))
averaging_frequency = 1000
average_monitor = TrainingDataMonitoring(observables,
Exemplo n.º 27
0
def main():
    mlp_hiddens = [1000]
    filter_sizes = [(9, 9), (5, 5), (5, 5)]
    feature_maps = [80, 50, 20]
    pooling_sizes = [(3, 3), (2, 2), (2, 2)]
    save_to = "DvC.pkl"
    image_size = (128, 128)
    output_size = 2
    learningRate = 0.1
    num_epochs = 300
    num_batches = None
    if socket.gethostname() == 'tim-X550JX':
        host_plot = 'http://*****:*****@ %s' %
             ('CNN ', datetime.datetime.now(), socket.gethostname()),
             channels=[['train_error_rate', 'valid_error_rate'],
                       ['train_total_gradient_norm']],
             after_epoch=True,
             server_url=host_plot))

    model = Model(cost)

    main_loop = MainLoop(algorithm,
                         stream_data_train,
                         model=model,
                         extensions=extensions)

    main_loop.run()
Exemplo n.º 28
0
def main(num_epochs,
         feature_maps=None,
         mlp_hiddens=None,
         conv_sizes=None,
         pool_sizes=None,
         batch_size=500,
         num_batches=None):

    ############# Architecture #############
    if feature_maps is None:
        feature_maps = [20, 50]
    if mlp_hiddens is None:
        mlp_hiddens = [500]
    if conv_sizes is None:
        conv_sizes = [5, 5]
    if pool_sizes is None:
        pool_sizes = [2, 2]
    image_size = (32, 32)
    batch_size = 50
    output_size = 2
    learningRate = 0.1
    num_epochs = 10
    num_batches = None
    delta = 0.01
    drop_prob = 0.5
    weight_noise = 0.75

    # Use ReLUs everywhere and softmax for the final prediction
    conv_activations = [Rectifier() for _ in feature_maps]
    mlp_activations = [Rectifier() for _ in mlp_hiddens] + [Softmax()]
    convnet = LeNet(conv_activations,
                    3,
                    image_size,
                    filter_sizes=zip(conv_sizes, conv_sizes),
                    feature_maps=feature_maps,
                    pooling_sizes=zip(pool_sizes, pool_sizes),
                    top_mlp_activations=mlp_activations,
                    top_mlp_dims=mlp_hiddens + [output_size],
                    border_mode='full',
                    weights_init=Uniform(width=.2),
                    biases_init=Constant(0))

    # We push initialization config to set different initialization schemes
    # for convolutional layers.

    convnet.push_initialization_config()
    convnet.layers[0].weights_init = Uniform(width=.2)
    convnet.layers[1].weights_init = Uniform(width=.09)
    convnet.top_mlp.linear_transformations[0].weights_init = Uniform(width=.08)
    convnet.top_mlp.linear_transformations[1].weights_init = Uniform(width=.11)
    convnet.initialize()
    logging.info(
        "Input dim: {} {} {}".format(*convnet.children[0].get_dim('input_')))
    for i, layer in enumerate(convnet.layers):
        if isinstance(layer, Activation):
            logging.info("Layer {} ({})".format(i, layer.__class__.__name__))
        else:
            logging.info("Layer {} ({}) dim: {} {} {}".format(
                i, layer.__class__.__name__, *layer.get_dim('output')))

    x = tensor.tensor4('image_features')
    y = tensor.lmatrix('targets')

    probs = (convnet.apply(x)).copy(name='probs')

    # Computational Graph just for cost for drop_out and noise application
    cg_probs = ComputationGraph([probs])
    inputs = VariableFilter(roles=[INPUT])(cg_probs.variables)
    weights = VariableFilter(roles=[FILTER, WEIGHT])(cg_probs.variables)

    ############# Regularization #############
    #regularization = 0
    logger.info('Applying regularization')
    regularization = delta * sum([(W**2).mean() for W in weights])
    probs.name = "reg_probs"

    ############# Guaussian Noise #############

    logger.info('Applying Gaussian noise')
    cg_train = apply_noise(cg_probs, weights, weight_noise)

    ############# Dropout #############

    logger.info('Applying dropout')
    cg_probs = apply_dropout(cg_probs, inputs, drop_prob)
    dropped_out = VariableFilter(roles=[DROPOUT])(cg_probs.variables)
    inputs_referenced = [var.tag.replacement_of for var in dropped_out]
    set(inputs) == set(inputs_referenced)

    ############# Batch normalization #############

    # recalculate probs after dropout and noise and regularization:
    probs = cg_probs.outputs[0] + regularization
    cost = (CategoricalCrossEntropy().apply(y.flatten(),
                                            probs).copy(name='cost'))
    error_rate = (MisclassificationRate().apply(y.flatten(),
                                                probs).copy(name='error_rate'))
    cg = ComputationGraph([probs, cost, error_rate])
    cg = apply_batch_normalization(cg)

    ########### Loading images #####################

    from fuel.datasets.dogs_vs_cats import DogsVsCats
    from fuel.streams import DataStream, ServerDataStream
    from fuel.schemes import ShuffledScheme
    from fuel.transformers.image import RandomFixedSizeCrop, MinimumImageDimensions, Random2DRotation
    from fuel.transformers import Flatten, Cast, ScaleAndShift

    def create_data(data):
        stream = DataStream(data,
                            iteration_scheme=ShuffledScheme(
                                data.num_examples, batch_size))
        stream_downscale = MinimumImageDimensions(
            stream, image_size, which_sources=('image_features', ))
        stream_rotate = Random2DRotation(stream_downscale,
                                         which_sources=('image_features', ))
        stream_max = ScikitResize(stream_rotate,
                                  image_size,
                                  which_sources=('image_features', ))
        stream_scale = ScaleAndShift(stream_max,
                                     1. / 255,
                                     0,
                                     which_sources=('image_features', ))
        stream_cast = Cast(stream_scale,
                           dtype='float32',
                           which_sources=('image_features', ))
        #stream_flat = Flatten(stream_scale, which_sources=('image_features',))

        return stream_cast

    stream_data_train = create_data(
        DogsVsCats(('train', ), subset=slice(0, 20)))
    stream_data_test = create_data(
        DogsVsCats(('train', ), subset=slice(20, 30)))

    # Train with simple SGD
    algorithm = GradientDescent(cost=cost,
                                parameters=cg.parameters,
                                step_rule=Scale(learning_rate=learningRate))
    #algorithm = GradientDescent(cost=cost, parameters=cg.parameters,step_rule=Adam(0.001))
    #algorithm.add_updates(extra_updates)

    # `Timing` extension reports time for reading data, aggregating a batch and monitoring;
    # `ProgressBar` displays a nice progress bar during training.
    extensions = []
    extensions.append(Timing())
    extensions.append(
        FinishAfter(after_n_epochs=num_epochs, after_n_batches=num_batches))
    extensions.append(
        DataStreamMonitoring([cost, error_rate],
                             stream_data_test,
                             prefix="valid"))
    extensions.append(
        TrainingDataMonitoring([
            cost, error_rate,
            aggregation.mean(algorithm.total_gradient_norm)
        ],
                               prefix="train",
                               after_epoch=True))
    #extensions.append(Checkpoint(save_to))
    extensions.append(ProgressBar())
    extensions.append(Printing())

    logger.info("Building the model")
    model = Model(cost)

    main_loop = MainLoop(algorithm,
                         stream_data_train,
                         model=model,
                         extensions=extensions)

    main_loop.run()
Exemplo n.º 29
0
mnist_train = MNIST("train")
train_stream = Flatten(
    DataStream.default_stream(dataset=mnist_train,
                              iteration_scheme=SequentialScheme(
                                  mnist_train.num_examples, 128)), )

# load testing data
mnist_test = MNIST("test")
test_stream = Flatten(
    DataStream.default_stream(dataset=mnist_test,
                              iteration_scheme=SequentialScheme(
                                  mnist_test.num_examples, 1024)), )

# train the model
from blocks.model import Model
main_loop = MainLoop(model=Model(cost),
                     data_stream=train_stream,
                     algorithm=GradientDescent(
                         cost=cost,
                         params=ComputationGraph(cost).parameters,
                         step_rule=Scale(learning_rate=0.1)),
                     extensions=[
                         FinishAfter(after_n_epochs=5),
                         DataStreamMonitoring(variables=[cost, error_rate],
                                              data_stream=test_stream,
                                              prefix="test"),
                         Printing()
                     ])

main_loop.run()
Exemplo n.º 30
0
def build_and_run(save_to,modelconfig,experimentconfig):
    """ part of this is adapted from lasagne tutorial""" 

    n, num_filters, image_size, num_blockstack = modelconfig['depth'], modelconfig['num_filters'], modelconfig['image_size'], modelconfig['num_blockstack']
    
    print("Amount of bottlenecks: %d" % n)

    # Prepare Theano variables for inputs and targets
    input_var = T.tensor4('image_features')
    #target_value = T.ivector('targets')
    target_var = T.lmatrix('targets')
    target_vec = T.extra_ops.to_one_hot(target_var[:,0],2)
    #target_var = T.matrix('targets')
    # Create residual net model
    print("Building model...")
    network = build_cnn(input_var, image_size, n, num_blockstack, num_filters)
    get_info(network)
    prediction = lasagne.utils.as_theano_expression(lasagne.layers.get_output(network))
    test_prediction = lasagne.utils.as_theano_expression(lasagne.layers.get_output(network,deterministic=True))

    # Loss function -> The objective to minimize 
    print("Instanciation of loss function...")
 
    #loss = CategoricalCrossEntropy().apply(target_var.flatten(), prediction)
    #test_loss = CategoricalCrossEntropy().apply(target_var.flatten(), test_prediction)
 #   loss = lasagne.objectives.categorical_crossentropy(prediction, target_var.flatten()).mean()
  #  test_loss = lasagne.objectives.categorical_crossentropy(test_prediction, target_var.flatten()).mean()
    loss = lasagne.objectives.squared_error(prediction,target_vec).mean()
    test_loss = lasagne.objectives.squared_error(test_prediction,target_vec).mean()
  #  loss = tensor.nnet.binary_crossentropy(prediction, target_var).mean()
  #  test_loss = tensor.nnet.binary_crossentropy(test_prediction, target_var).mean()
    test_loss.name = "loss"

#    loss.name = 'x-ent_error'
#    loss.name = 'sqr_error'
    layers = lasagne.layers.get_all_layers(network)

    #l1 and l2 regularization
    #pondlayers = {x:0.000025 for i,x in enumerate(layers)}
    #l1_penality = lasagne.regularization.regularize_layer_params_weighted(pondlayers, lasagne.regularization.l2)
    #l2_penality = lasagne.regularization.regularize_layer_params(layers[len(layers)/4:], lasagne.regularization.l1) * 25e-6
    #reg_penalty = l1_penality + l2_penality
    #reg_penalty.name = 'reg_penalty'
    #loss = loss + reg_penalty
    loss.name = 'reg_loss'
    error_rate = MisclassificationRate().apply(target_var.flatten(), test_prediction).copy(
            name='error_rate')

    
    # Load the dataset
    print("Loading data...")
    istest = 'test' in experimentconfig.keys()
    if istest:
        print("Using test stream")
    train_stream, valid_stream, test_stream = get_stream(experimentconfig['batch_size'],image_size,test=istest)

    # Defining step rule and algorithm
    if 'step_rule' in experimentconfig.keys() and not experimentconfig['step_rule'] is None :
        step_rule = experimentconfig['step_rule'](learning_rate=experimentconfig['learning_rate'])
    else :
        step_rule=Scale(learning_rate=experimentconfig['learning_rate'])

    params = map(lasagne.utils.as_theano_expression,lasagne.layers.get_all_params(network, trainable=True))
    print("Initializing algorithm")
    algorithm = GradientDescent(
                cost=loss, gradients={var:T.grad(loss,var) for var in params},#parameters=cg.parameters, #params
                step_rule=step_rule)

    #algorithm.add_updates(extra_updates)


    grad_norm = aggregation.mean(algorithm.total_gradient_norm)
    grad_norm.name = "grad_norm"

    print("Initializing extensions...")
    plot = Plot(save_to, channels=[['train_loss','valid_loss'], 
['train_grad_norm'],
#['train_grad_norm','train_reg_penalty'],
['train_error_rate','valid_error_rate']], server_url='http://hades.calculquebec.ca:5042')    

    checkpoint = Checkpoint('models/best_'+save_to+'.tar')
  #  checkpoint.add_condition(['after_n_batches=25'],

    checkpoint.add_condition(['after_epoch'],
                         predicate=OnLogRecord('valid_error_rate_best_so_far'))

    #Defining extensions
    extensions = [Timing(),
                  FinishAfter(after_n_epochs=experimentconfig['num_epochs'],
                              after_n_batches=experimentconfig['num_batches']),
                  TrainingDataMonitoring([test_loss, error_rate, grad_norm], # reg_penalty],
                  prefix="train", after_epoch=True), #after_n_epochs=1
                  DataStreamMonitoring([test_loss, error_rate],valid_stream,prefix="valid", after_epoch=True), #after_n_epochs=1
                  plot,
                  #Checkpoint(save_to,after_n_epochs=5),
                  #ProgressBar(),
             #     Plot(save_to, channels=[['train_loss','valid_loss'], ['train_error_rate','valid_error_rate']], server_url='http://hades.calculquebec.ca:5042'), #'grad_norm'
                  #       after_batch=True),
                  Printing(after_epoch=True),
                  TrackTheBest('valid_error_rate',min), #Keep best
                  checkpoint,  #Save best
                  FinishIfNoImprovementAfter('valid_error_rate_best_so_far', epochs=5)] # Early-stopping

 #   model = Model(loss)
 #   print("Model",model)


    main_loop = MainLoop(
        algorithm,
        train_stream,
       # model=model,
        extensions=extensions)
    print("Starting main loop...")

    main_loop.run()