コード例 #1
0
def test_simple_perceptron():
    # Loading dataset
    trainset, validset, testset = load_mnist()

    # Creating model
    nb_classes = 10
    model = Perceptron(trainset.input_size, nb_classes)
    model.initialize()  # By default, uniform initialization.

    # Building optimizer
    loss = NLL(model, trainset)
    optimizer = SGD(loss=loss)
    optimizer.append_direction_modifier(ConstantLearningRate(0.1))

    # Use mini batches of 100 examples.
    batch_scheduler = MiniBatchScheduler(trainset, 100)

    # Build trainer and add some tasks.
    trainer = Trainer(optimizer, batch_scheduler)

    # Print time for one epoch
    trainer.append_task(tasks.PrintEpochDuration())
    trainer.append_task(tasks.PrintTrainingDuration())

    # Log training error
    loss_monitor = views.MonitorVariable(loss.loss)
    avg_loss = tasks.AveragePerEpoch(loss_monitor)
    accum = tasks.Accumulator(loss_monitor)
    logger = tasks.Logger(loss_monitor, avg_loss)
    trainer.append_task(logger, avg_loss, accum)

    # Print NLL mean/stderror.
    nll = views.LossView(loss=NLL(model, validset),
                         batch_scheduler=FullBatchScheduler(validset))
    trainer.append_task(
        tasks.Print("Validset - NLL          : {0:.1%} ± {1:.1%}", nll.mean,
                    nll.stderror))

    # Print mean/stderror of classification errors.
    classif_error = views.LossView(
        loss=ClassificationError(model, validset),
        batch_scheduler=FullBatchScheduler(validset))
    trainer.append_task(
        tasks.Print("Validset - Classif error: {0:.1%} ± {1:.1%}",
                    classif_error.mean, classif_error.stderror))

    # Train for 10 epochs (stopping criteria should be added at the end).
    trainer.append_task(stopping_criteria.MaxEpochStopping(10))
    trainer.train()
コード例 #2
0
    def _build_trainer(nb_epochs):
        print("Will train Convoluational Deep NADE for a total of {0} epochs.".
              format(nb_epochs))

        with Timer("Building model"):
            builder = DeepConvNADEBuilder(image_shape=image_shape,
                                          nb_channels=nb_channels,
                                          use_mask_as_input=use_mask_as_input)

            convnet_blueprint = "64@2x2(valid) -> 1@2x2(full)"
            fullnet_blueprint = "5 -> 16"
            print("Convnet:", convnet_blueprint)
            print("Fullnet:", fullnet_blueprint)
            builder.build_convnet_from_blueprint(convnet_blueprint)
            builder.build_fullnet_from_blueprint(fullnet_blueprint)

            model = builder.build()
            model.initialize(initer.UniformInitializer(random_seed=1234))

        with Timer("Building optimizer"):
            loss = BinaryCrossEntropyEstimateWithAutoRegressiveMask(
                model, trainset)

            optimizer = SGD(loss=loss)
            optimizer.append_direction_modifier(ConstantLearningRate(0.001))

        with Timer("Building trainer"):
            batch_scheduler = MiniBatchSchedulerWithAutoregressiveMask(
                trainset, batch_size)

            trainer = Trainer(optimizer, batch_scheduler)

            # Print time for one epoch
            trainer.append_task(tasks.PrintEpochDuration())
            trainer.append_task(tasks.PrintTrainingDuration())

            # Log training error
            loss_monitor = views.MonitorVariable(loss.loss)
            avg_loss = tasks.AveragePerEpoch(loss_monitor)
            accum = tasks.Accumulator(loss_monitor)
            logger = tasks.Logger(loss_monitor, avg_loss)
            trainer.append_task(logger, avg_loss, accum)

            # Print average training loss.
            trainer.append_task(
                tasks.Print("Avg. training loss:     : {}", avg_loss))

            # Print NLL mean/stderror.
            nll = views.LossView(
                loss=BinaryCrossEntropyEstimateWithAutoRegressiveMask(
                    model, validset),
                batch_scheduler=MiniBatchSchedulerWithAutoregressiveMask(
                    validset, batch_size=len(validset), keep_mask=True))
            trainer.append_task(
                tasks.Print("Validset - NLL          : {0:.2f} ± {1:.2f}",
                            nll.mean, nll.stderror))

            trainer.append_task(stopping_criteria.MaxEpochStopping(nb_epochs))

            return trainer, nll, logger
コード例 #3
0
def estimate_NLL(model, dataset, seed=1234, batch_size=None):
    if batch_size is None:
        batch_size = len(dataset)

    loss = BinaryCrossEntropyEstimateWithAutoRegressiveMask(model, dataset)
    status = Status()

    batch_scheduler = MiniBatchSchedulerWithAutoregressiveMask(
        dataset,
        batch_size=len(dataset),
        use_mask_as_input=model.nb_channels == 2,
        keep_mask=True,
        seed=seed)

    nll = views.LossView(loss=loss, batch_scheduler=batch_scheduler)

    # Try different size of batch size.
    while batch_size >= 1:
        print("Estimating NLL using batch size of {}".format(batch_size))
        try:
            batch_scheduler.batch_size = min(batch_size, len(dataset))
            return {
                "mean": float(nll.mean.view(status)),
                "stderror": float(nll.stderror.view(status))
            }

        except MemoryError as e:
            # Probably not enough memory on GPU
            #print("\n".join([l for l in str(e).split("\n") if "allocating" in l]))
            pass

        except RuntimeError as e:
            # Probably RuntimeError: BaseGpuCorrMM: Failed to allocate output of
            if "allocate" not in str(e):
                raise e

        print(
            "*An error occured while estimating NLL. Will try a smaller batch size."
        )
        batch_size = batch_size // 2

    raise RuntimeError(
        "Cannot find a suitable batch size to estimate NLL. Try using CPU instead or a GPU with more memory."
    )
コード例 #4
0
ファイル: track.py プロジェクト: szho42/learn2track
def compute_loss_errors(streamlines, model, hyperparams):
    # Create dummy dataset for these new streamlines.
    tracto_data = neurotools.TractographyData(None, None, None)
    tracto_data.add(streamlines, bundle_name="Generated")
    tracto_data.subject_id = 0
    dataset = datasets.TractographyDataset([tracto_data],
                                           "Generated",
                                           keep_on_cpu=True)

    # Override K for gru_multistep
    if 'k' in hyperparams:
        hyperparams['k'] = 1
    batch_scheduler = batch_scheduler_factory(hyperparams,
                                              dataset,
                                              train_mode=False,
                                              batch_size_override=1000,
                                              use_data_augment=False)
    loss = loss_factory(hyperparams, model, dataset)
    loss_view = views.LossView(loss=loss, batch_scheduler=batch_scheduler)
    return loss_view.losses.view()
コード例 #5
0
    def _build_trainer(nb_epochs, optimizer_cls):
        print(
            "Will build a trainer is going to train a Perceptron for {0} epochs."
            .format(nb_epochs))

        print("Building model")
        model = Perceptron(trainset.input_size, nb_classes)
        model.initialize(initer.UniformInitializer(random_seed=1234))

        print("Building optimizer")
        loss = NLL(model, trainset)
        optimizer = optimizer_cls(loss=loss)
        print("Optimizer: {}".format(type(optimizer).__name__))
        #optimizer = SGD(loss=loss)
        #optimizer.append_direction_modifier(ConstantLearningRate(0.1))

        # Use mini batches of 100 examples.
        batch_scheduler = MiniBatchScheduler(trainset, 100)

        print("Building trainer")
        trainer = Trainer(optimizer, batch_scheduler)

        # Print time for one epoch
        trainer.append_task(tasks.PrintEpochDuration())
        trainer.append_task(tasks.PrintTrainingDuration())

        # Log training error
        loss_monitor = views.MonitorVariable(loss.loss)
        avg_loss = tasks.AveragePerEpoch(loss_monitor)

        # Print NLL mean/stderror.
        nll = views.LossView(loss=NLL(model, validset),
                             batch_scheduler=FullBatchScheduler(validset))
        logger = tasks.Logger(loss_monitor, avg_loss, nll.mean)
        trainer.append_task(logger, avg_loss)

        # Train for `nb_epochs` epochs (stopping criteria should be added at the end).
        trainer.append_task(stopping_criteria.MaxEpochStopping(nb_epochs))

        return trainer, nll, logger
コード例 #6
0
def test_simple_convnade():
    nb_kernels = 8
    kernel_shape = (2, 2)
    hidden_activation = "sigmoid"
    consider_mask_as_channel = True
    batch_size = 1024
    ordering_seed = 1234
    max_epoch = 3
    nb_orderings = 1

    print("Will train Convoluational Deep NADE for a total of {0} epochs.".
          format(max_epoch))

    with Timer("Loading/processing binarized MNIST"):
        trainset, validset, testset = load_binarized_mnist()

        # Extract the center patch (4x4 pixels) of each image.
        indices_to_keep = [
            348, 349, 350, 351, 376, 377, 378, 379, 404, 405, 406, 407, 432,
            433, 434, 435
        ]

        trainset = Dataset(trainset.inputs.get_value()[:, indices_to_keep],
                           trainset.inputs.get_value()[:, indices_to_keep],
                           name="trainset")
        validset = Dataset(validset.inputs.get_value()[:, indices_to_keep],
                           validset.inputs.get_value()[:, indices_to_keep],
                           name="validset")
        testset = Dataset(testset.inputs.get_value()[:, indices_to_keep],
                          testset.inputs.get_value()[:, indices_to_keep],
                          name="testset")

        image_shape = (4, 4)
        nb_channels = 1

    with Timer("Building model"):
        builder = DeepConvNADEBuilder(image_shape=image_shape,
                                      nb_channels=nb_channels,
                                      consider_mask_as_channel=True)

        convnet_blueprint = "64@2x2(valid) -> 1@2x2(full)"
        fullnet_blueprint = "5 -> 16"
        print("Convnet:", convnet_blueprint)
        print("Fullnet:", fullnet_blueprint)
        builder.build_convnet_from_blueprint(convnet_blueprint)
        builder.build_fullnet_from_blueprint(fullnet_blueprint)

        model = builder.build()
        model.initialize()  # By default, uniform initialization.

    with Timer("Building optimizer"):
        loss = BinaryCrossEntropyEstimateWithAutoRegressiveMask(
            model, trainset)

        optimizer = SGD(loss=loss)
        optimizer.append_direction_modifier(ConstantLearningRate(0.001))

    with Timer("Building trainer"):
        batch_scheduler = MiniBatchSchedulerWithAutoregressiveMask(
            trainset, batch_size)

        trainer = Trainer(optimizer, batch_scheduler)

        trainer.append_task(stopping_criteria.MaxEpochStopping(max_epoch))

        # Print time for one epoch
        trainer.append_task(tasks.PrintEpochDuration())
        trainer.append_task(tasks.PrintTrainingDuration())

        # Log training error
        loss_monitor = views.MonitorVariable(loss.loss)
        avg_loss = tasks.AveragePerEpoch(loss_monitor)
        accum = tasks.Accumulator(loss_monitor)
        logger = tasks.Logger(loss_monitor, avg_loss)
        trainer.append_task(logger, avg_loss, accum)

        # Print average training loss.
        trainer.append_task(
            tasks.Print("Avg. training loss:     : {}", avg_loss))

        # Print NLL mean/stderror.
        nll = views.LossView(
            loss=BinaryCrossEntropyEstimateWithAutoRegressiveMask(
                model, validset),
            batch_scheduler=MiniBatchSchedulerWithAutoregressiveMask(
                validset, batch_size=len(validset)))
        trainer.append_task(
            tasks.Print("Validset - NLL          : {0:.2f} ± {1:.2f}",
                        nll.mean, nll.stderror))

        trainer.build_theano_graph()

    with Timer("Training"):
        trainer.train()

    with Timer("Checking the probs for all possible inputs sum to 1"):
        # rng = np.random.RandomState(ordering_seed)
        D = np.prod(image_shape)

        batch_scheduler = BatchSchedulerWithAutoregressiveMasks(
            validset,
            batch_size=len(validset),
            batch_id=0,
            ordering_id=0,
            concatenate_mask=model.nb_channels == 2,
            seed=42)
        nll = views.LossView(
            loss=NllUsingBinaryCrossEntropyWithAutoRegressiveMask(
                model, validset, batch_scheduler.mod),
            batch_scheduler=batch_scheduler)
        nlls_xod_given_xoltd = nll.losses.view(Status())
        nlls = np.sum(nlls_xod_given_xoltd.reshape(-1, len(validset)), axis=0)
        nll_validset = np.mean(nlls)
        print("Sum of NLL for validset:", nll_validset)

        inputs = cartesian([[0, 1]] * int(D), dtype=np.float32)
        dataset = ReconstructionDataset(inputs)
        batch_scheduler = BatchSchedulerWithAutoregressiveMasks(
            dataset,
            batch_size=len(dataset),
            batch_id=0,
            ordering_id=0,
            concatenate_mask=model.nb_channels == 2,
            seed=42)
        nll = views.LossView(
            loss=NllUsingBinaryCrossEntropyWithAutoRegressiveMask(
                model, dataset, batch_scheduler.mod),
            batch_scheduler=batch_scheduler)
        nlls_xod_given_xoltd = nll.losses.view(Status())
        nlls = np.sum(nlls_xod_given_xoltd.reshape(-1, len(dataset)), axis=0)
        p_x = np.exp(np.logaddexp.reduce(-nlls))
        print("Sum of p(x) for all x:", p_x)
        assert_almost_equal(p_x, 1., decimal=5)
コード例 #7
0
def main():
    parser = build_parser()
    args = parser.parse_args()
    print(args)

    if min(args.keep_top) < 0:
        parser.error("--keep-top must be between in [0, 1].")

    # Get experiment folder
    experiment_path = args.name
    if not os.path.isdir(experiment_path):
        # If not a directory, it must be the name of the experiment.
        experiment_path = pjoin(".", "experiments", args.name)

    if not os.path.isdir(experiment_path):
        parser.error('Cannot find experiment: {0}!'.format(args.name))

    # Load experiments hyperparameters
    try:
        hyperparams = smartutils.load_dict_from_json_file(
            pjoin(experiment_path, "hyperparams.json"))
    except FileNotFoundError:
        hyperparams = smartutils.load_dict_from_json_file(
            pjoin(experiment_path, "..", "hyperparams.json"))

    # Use this for hyperparams added in a new version, but nonexistent from older versions
    retrocompatibility_defaults = {
        'feed_previous_direction': False,
        'predict_offset': False,
        'normalize': False,
        'keep_step_size': False,
        'sort_streamlines': False
    }
    for new_hyperparams, default_value in retrocompatibility_defaults.items():
        if new_hyperparams not in hyperparams:
            hyperparams[new_hyperparams] = default_value

    with Timer("Loading signal data and tractogram", newline=True):
        volume_manager = VolumeManager()
        dataset = datasets.load_tractography_dataset_from_dwi_and_tractogram(
            args.signal,
            args.tractogram,
            volume_manager,
            use_sh_coeffs=hyperparams['use_sh_coeffs'],
            bvals=args.bvals,
            bvecs=args.bvecs,
            step_size=args.step_size)
        print("Dataset size:", len(dataset))

        if vizu_available and args.vizu:
            vizu.check_dataset_integrity(dataset, subset=0.2)

    with Timer("Loading model"):
        loss_type = args.loss_type
        model = None
        if hyperparams['model'] == 'gru_regression':
            from learn2track.models import GRU_Regression
            model = GRU_Regression.create(experiment_path,
                                          volume_manager=volume_manager)
        elif hyperparams['model'] == 'gru_mixture':
            from learn2track.models import GRU_Mixture
            model = GRU_Mixture.create(experiment_path,
                                       volume_manager=volume_manager)
        elif hyperparams['model'] == 'gru_multistep':
            from learn2track.models import GRU_Multistep_Gaussian
            model = GRU_Multistep_Gaussian.create(
                experiment_path, volume_manager=volume_manager)
            model.k = 1
            model.m = 1
        elif hyperparams['model'] == 'ffnn_regression':
            from learn2track.models import FFNN_Regression
            model = FFNN_Regression.create(experiment_path,
                                           volume_manager=volume_manager)

            if loss_type in ['l2_sum', 'l2_mean']:
                loss_type = "expected_value"

        else:
            raise NameError("Unknown model: {}".format(hyperparams['model']))

    with Timer("Building evaluation function"):
        # Override K for gru_multistep
        if 'k' in hyperparams:
            hyperparams['k'] = 1

        batch_scheduler = batch_scheduler_factory(
            hyperparams,
            dataset,
            use_data_augment=
            False,  # Otherwise it doubles the number of losses :-/
            train_mode=False,
            batch_size_override=args.batch_size)
        loss = loss_factory(hyperparams, model, dataset, loss_type=loss_type)
        l2_error = views.LossView(loss=loss, batch_scheduler=batch_scheduler)

    with Timer("Scoring...", newline=True):
        dummy_status = Status()  # Forces recomputing results
        losses = l2_error.losses.view(dummy_status)

        if hyperparams['model'] == 'ffnn_regression':
            _losses = dataset.streamlines.copy()
            _losses._data = losses.copy()
            _losses._lengths -= 1
            _losses._offsets -= np.arange(len(dataset.streamlines))

            if args.loss_type == 'l2_sum':
                losses = np.asarray([l.sum() for l in _losses])
            elif args.loss_type == 'l2_mean':
                losses = np.asarray([l.mean() for l in _losses])

        mean = float(l2_error.mean.view(dummy_status))
        stderror = float(l2_error.stderror.view(dummy_status))

        print("Loss: {:.4f} ± {:.4f}".format(mean, stderror))
        print("Min: {:.4f}".format(losses.min()))
        print("Max: {:.4f}".format(losses.max()))
        print("Percentiles: {}".format(
            np.percentile(losses, [0, 25, 50, 75, 100])))

    with Timer("Saving streamlines"):
        nii = dataset.subjects[0].signal
        tractogram = nib.streamlines.Tractogram(
            dataset.streamlines[batch_scheduler.indices],
            affine_to_rasmm=nii.affine)
        tractogram.data_per_streamline['loss'] = losses

        header = {}
        header[Field.VOXEL_TO_RASMM] = nii.affine.copy()
        header[Field.VOXEL_SIZES] = nii.header.get_zooms()[:3]
        header[Field.DIMENSIONS] = nii.shape[:3]
        header[Field.VOXEL_ORDER] = "".join(aff2axcodes(nii.affine))

        nib.streamlines.save(tractogram.copy(), args.out, header=header)

    if len(args.keep_top) > 0:
        for keep_top in args.keep_top:
            with Timer("Saving top {}% streamlines".format(keep_top)):
                idx = np.argsort(losses)
                idx = idx[:int(keep_top * len(losses))]
                print("Keeping {}/{} streamlines".format(
                    len(idx), len(losses)))
                sub_tractogram = tractogram[idx]
                out_filename = args.out[:-4] + "_top{}".format(
                    keep_top) + ".tck"
                nib.streamlines.save(sub_tractogram, out_filename)
コード例 #8
0
def main():
    parser = buildArgsParser()
    args = parser.parse_args()

    # Extract experiments hyperparameters
    hyperparams = dict(vars(args))

    # Remove hyperparams that should not be part of the hash
    del hyperparams['max_epoch']
    del hyperparams['keep']
    del hyperparams['force']
    del hyperparams['name']

    # Get/generate experiment name
    experiment_name = args.name
    if experiment_name is None:
        experiment_name = utils.generate_uid_from_string(repr(hyperparams))

    # Create experiment folder
    experiment_path = pjoin(".", "experiments", experiment_name)
    resuming = False
    if os.path.isdir(experiment_path) and not args.force:
        resuming = True
        print("### Resuming experiment ({0}). ###\n".format(experiment_name))
        # Check if provided hyperparams match those in the experiment folder
        hyperparams_loaded = utils.load_dict_from_json_file(pjoin(experiment_path, "hyperparams.json"))
        if hyperparams != hyperparams_loaded:
            print("{\n" + "\n".join(["{}: {}".format(k, hyperparams[k]) for k in sorted(hyperparams.keys())]) + "\n}")
            print("{\n" + "\n".join(["{}: {}".format(k, hyperparams_loaded[k]) for k in sorted(hyperparams_loaded.keys())]) + "\n}")
            print("The arguments provided are different than the one saved. Use --force if you are certain.\nQuitting.")
            sys.exit(1)
    else:
        if os.path.isdir(experiment_path):
            shutil.rmtree(experiment_path)

        os.makedirs(experiment_path)
        utils.save_dict_to_json_file(pjoin(experiment_path, "hyperparams.json"), hyperparams)

    with Timer("Loading dataset"):
        trainset, validset, testset = datasets.load(args.dataset)

        image_shape = (28, 28)
        nb_channels = 1 + (args.use_mask_as_input is True)

        batch_scheduler = MiniBatchSchedulerWithAutoregressiveMask(trainset, args.batch_size,
                                                                   use_mask_as_input=args.use_mask_as_input,
                                                                   seed=args.ordering_seed)
        print("{} updates per epoch.".format(len(batch_scheduler)))

    with Timer("Building model"):
        if args.use_lasagne:
            if args.with_residual:
                model = DeepConvNadeWithResidualUsingLasagne(image_shape=image_shape,
                                                             nb_channels=nb_channels,
                                                             convnet_blueprint=args.convnet_blueprint,
                                                             fullnet_blueprint=args.fullnet_blueprint,
                                                             hidden_activation=args.hidden_activation,
                                                             use_mask_as_input=args.use_mask_as_input)
            else:
                model = DeepConvNadeUsingLasagne(image_shape=image_shape,
                                                 nb_channels=nb_channels,
                                                 convnet_blueprint=args.convnet_blueprint,
                                                 fullnet_blueprint=args.fullnet_blueprint,
                                                 hidden_activation=args.hidden_activation,
                                                 use_mask_as_input=args.use_mask_as_input,
                                                 use_batch_norm=args.batch_norm)

        elif args.with_residual:
            model = DeepConvNADEWithResidual(image_shape=image_shape,
                                             nb_channels=nb_channels,
                                             convnet_blueprint=args.convnet_blueprint,
                                             fullnet_blueprint=args.fullnet_blueprint,
                                             hidden_activation=args.hidden_activation,
                                             use_mask_as_input=args.use_mask_as_input)

        else:
            builder = DeepConvNADEBuilder(image_shape=image_shape,
                                          nb_channels=nb_channels,
                                          hidden_activation=args.hidden_activation,
                                          use_mask_as_input=args.use_mask_as_input)

            if args.blueprints_seed is not None:
                convnet_blueprint, fullnet_blueprint = generate_blueprints(args.blueprint_seed, image_shape[0])
                builder.build_convnet_from_blueprint(convnet_blueprint)
                builder.build_fullnet_from_blueprint(fullnet_blueprint)
            else:
                if args.convnet_blueprint is not None:
                    builder.build_convnet_from_blueprint(args.convnet_blueprint)

                if args.fullnet_blueprint is not None:
                    builder.build_fullnet_from_blueprint(args.fullnet_blueprint)

            model = builder.build()
            # print(str(model.convnet))
            # print(str(model.fullnet))

        model.initialize(weigths_initializer_factory(args.weights_initialization,
                                                     seed=args.initialization_seed))
        print(str(model))

    with Timer("Building optimizer"):
        loss = BinaryCrossEntropyEstimateWithAutoRegressiveMask(model, trainset)
        optimizer = optimizer_factory(hyperparams, loss)

    with Timer("Building trainer"):
        trainer = Trainer(optimizer, batch_scheduler)

        if args.max_epoch is not None:
            trainer.append_task(stopping_criteria.MaxEpochStopping(args.max_epoch))

        # Print time for one epoch
        trainer.append_task(tasks.PrintEpochDuration())
        trainer.append_task(tasks.PrintTrainingDuration())

        # Log training error
        loss_monitor = views.MonitorVariable(loss.loss)
        avg_loss = tasks.AveragePerEpoch(loss_monitor)
        accum = tasks.Accumulator(loss_monitor)
        logger = tasks.Logger(loss_monitor, avg_loss)
        trainer.append_task(logger, avg_loss, accum)

        # Print average training loss.
        trainer.append_task(tasks.Print("Avg. training loss:     : {}", avg_loss))

        # Print NLL mean/stderror.
        model.deterministic = True  # For batch normalization, see https://github.com/Lasagne/Lasagne/blob/master/lasagne/layers/normalization.py#L198
        nll = views.LossView(loss=BinaryCrossEntropyEstimateWithAutoRegressiveMask(model, validset),
                             batch_scheduler=MiniBatchSchedulerWithAutoregressiveMask(validset, batch_size=0.1*len(validset),
                                                                                      use_mask_as_input=args.use_mask_as_input,
                                                                                      keep_mask=True,
                                                                                      seed=args.ordering_seed+1))
        # trainer.append_task(tasks.Print("Validset - NLL          : {0:.2f} ± {1:.2f}", nll.mean, nll.stderror, each_k_update=100))
        trainer.append_task(tasks.Print("Validset - NLL          : {0:.2f} ± {1:.2f}", nll.mean, nll.stderror))

        # direction_norm = views.MonitorVariable(T.sqrt(sum(map(lambda d: T.sqr(d).sum(), loss.gradients.values()))))
        # trainer.append_task(tasks.Print("||d|| : {0:.4f}", direction_norm, each_k_update=50))

        # Save training progression
        def save_model(*args):
            trainer.save(experiment_path)

        trainer.append_task(stopping_criteria.EarlyStopping(nll.mean, lookahead=args.lookahead, eps=args.lookahead_eps, callback=save_model))

        trainer.build_theano_graph()

    if resuming:
        with Timer("Loading"):
            trainer.load(experiment_path)

    with Timer("Training"):
        trainer.train()

    trainer.save(experiment_path)
    model.save(experiment_path)
コード例 #9
0
def main():
    parser = build_argparser()
    args = parser.parse_args()
    print(args)
    print("Using Theano v.{}".format(theano.version.short_version))

    hyperparams_to_exclude = ['max_epoch', 'force', 'name', 'view', 'shuffle_streamlines']
    # Use this for hyperparams added in a new version, but nonexistent from older versions
    retrocompatibility_defaults = {'feed_previous_direction': False,
                                   'predict_offset': False,
                                   'normalize': False,
                                   'sort_streamlines': False,
                                   'keep_step_size': False,
                                   'use_layer_normalization': False,
                                   'drop_prob': 0.,
                                   'use_zoneout': False,
                                   'skip_connections': False}
    experiment_path, hyperparams, resuming = utils.maybe_create_experiment_folder(args, exclude=hyperparams_to_exclude,
                                                                                  retrocompatibility_defaults=retrocompatibility_defaults)

    # Log the command currently running.
    with open(pjoin(experiment_path, 'cmd.txt'), 'a') as f:
        f.write(" ".join(sys.argv) + "\n")

    print("Resuming:" if resuming else "Creating:", experiment_path)

    with Timer("Loading dataset", newline=True):
        trainset_volume_manager = VolumeManager()
        validset_volume_manager = VolumeManager()
        trainset = datasets.load_tractography_dataset(args.train_subjects, trainset_volume_manager, name="trainset",
                                                      use_sh_coeffs=args.use_sh_coeffs)
        validset = datasets.load_tractography_dataset(args.valid_subjects, validset_volume_manager, name="validset",
                                                      use_sh_coeffs=args.use_sh_coeffs)
        print("Dataset sizes:", len(trainset), " |", len(validset))

        batch_scheduler = batch_scheduler_factory(hyperparams, dataset=trainset, train_mode=True)
        print("An epoch will be composed of {} updates.".format(batch_scheduler.nb_updates_per_epoch))
        print(trainset_volume_manager.data_dimension, args.hidden_sizes, batch_scheduler.target_size)

    with Timer("Creating model"):
        input_size = trainset_volume_manager.data_dimension
        if hyperparams['feed_previous_direction']:
            input_size += 3

        model = model_factory(hyperparams,
                              input_size=input_size,
                              output_size=batch_scheduler.target_size,
                              volume_manager=trainset_volume_manager)
        model.initialize(weigths_initializer_factory(args.weights_initialization,
                                                     seed=args.initialization_seed))

    with Timer("Building optimizer"):
        loss = loss_factory(hyperparams, model, trainset)

        if args.clip_gradient is not None:
            loss.append_gradient_modifier(DirectionClipping(threshold=args.clip_gradient))

        optimizer = optimizer_factory(hyperparams, loss)

    with Timer("Building trainer"):
        trainer = Trainer(optimizer, batch_scheduler)

        # Log training error
        loss_monitor = views.MonitorVariable(loss.loss)
        avg_loss = tasks.AveragePerEpoch(loss_monitor)
        trainer.append_task(avg_loss)

        # Print average training loss.
        trainer.append_task(tasks.Print("Avg. training loss:         : {}", avg_loss))

        # if args.learn_to_stop:
        #     l2err_monitor = views.MonitorVariable(T.mean(loss.mean_sqr_error))
        #     avg_l2err = tasks.AveragePerEpoch(l2err_monitor)
        #     trainer.append_task(avg_l2err)
        #
        #     crossentropy_monitor = views.MonitorVariable(T.mean(loss.cross_entropy))
        #     avg_crossentropy = tasks.AveragePerEpoch(crossentropy_monitor)
        #     trainer.append_task(avg_crossentropy)
        #
        #     trainer.append_task(tasks.Print("Avg. training L2 err:       : {}", avg_l2err))
        #     trainer.append_task(tasks.Print("Avg. training stopping:     : {}", avg_crossentropy))
        #     trainer.append_task(tasks.Print("L2 err : {0:.4f}", l2err_monitor, each_k_update=100))
        #     trainer.append_task(tasks.Print("stopping : {0:.4f}", crossentropy_monitor, each_k_update=100))

        # Print NLL mean/stderror.
        # train_loss = L2DistanceForSequences(model, trainset)
        # train_batch_scheduler = StreamlinesBatchScheduler(trainset, batch_size=1000,
        #                                                   noisy_streamlines_sigma=None,
        #                                                   nb_updates_per_epoch=None,
        #                                                   seed=1234)

        # train_error = views.LossView(loss=train_loss, batch_scheduler=train_batch_scheduler)
        # trainer.append_task(tasks.Print("Trainset - Error        : {0:.2f} | {1:.2f}", train_error.sum, train_error.mean))

        # HACK: To make sure all subjects in the volume_manager are used in a batch, we have to split the trainset/validset in 2 volume managers
        model.volume_manager = validset_volume_manager
        model.drop_prob = 0.  # Do not use dropout/zoneout for evaluation
        valid_loss = loss_factory(hyperparams, model, validset)
        valid_batch_scheduler = batch_scheduler_factory(hyperparams,
                                                        dataset=validset,
                                                        train_mode=False)

        valid_error = views.LossView(loss=valid_loss, batch_scheduler=valid_batch_scheduler)
        trainer.append_task(tasks.Print("Validset - Error        : {0:.2f} | {1:.2f}", valid_error.sum, valid_error.mean))

        if hyperparams['model'] == 'ffnn_regression':
            valid_batch_scheduler2 = batch_scheduler_factory(hyperparams,
                                                             dataset=validset,
                                                             train_mode=False)

            valid_l2 = loss_factory(hyperparams, model, validset, loss_type="expected_value")
            valid_l2_error = views.LossView(loss=valid_l2, batch_scheduler=valid_batch_scheduler2)
            trainer.append_task(tasks.Print("Validset - {}".format(valid_l2.__class__.__name__) + "\t: {0:.2f} | {1:.2f}", valid_l2_error.sum, valid_l2_error.mean))

        # HACK: Restore trainset volume manager
        model.volume_manager = trainset_volume_manager
        model.drop_prob = hyperparams['drop_prob']  # Restore dropout

        lookahead_loss = valid_error.sum

        direction_norm = views.MonitorVariable(T.sqrt(sum(map(lambda d: T.sqr(d).sum(), loss.gradients.values()))))
        # trainer.append_task(tasks.Print("||d|| : {0:.4f}", direction_norm))

        # logger = tasks.Logger(train_error.mean, valid_error.mean, valid_error.sum, direction_norm)
        logger = tasks.Logger(valid_error.mean, valid_error.sum, direction_norm)
        trainer.append_task(logger)

        if args.view:
            import pylab as plt

            def _plot(*args, **kwargs):
                plt.figure(1)
                plt.clf()
                plt.show(False)
                plt.subplot(121)
                plt.plot(np.array(logger.get_variable_history(0)).flatten(), label="Train")
                plt.plot(np.array(logger.get_variable_history(1)).flatten(), label="Valid")
                plt.legend()

                plt.subplot(122)
                plt.plot(np.array(logger.get_variable_history(3)).flatten(), label="||d'||")
                plt.draw()

            trainer.append_task(tasks.Callback(_plot))

        # Callback function to stop training if NaN is detected.
        def detect_nan(obj, status):
            if np.isnan(model.parameters[0].get_value().sum()):
                print("NaN detected! Stopping training now.")
                sys.exit()

        trainer.append_task(tasks.Callback(detect_nan, each_k_update=1))

        # Callback function to save training progression.
        def save_training(obj, status):
            trainer.save(experiment_path)

        trainer.append_task(tasks.Callback(save_training))

        # Early stopping with a callback for saving every time model improves.
        def save_improvement(obj, status):
            """ Save best model and training progression. """
            if np.isnan(model.parameters[0].get_value().sum()):
                print("NaN detected! Not saving the model. Crashing now.")
                sys.exit()

            print("*** Best epoch: {0} ***\n".format(obj.best_epoch))
            model.save(experiment_path)

        # Print time for one epoch
        trainer.append_task(tasks.PrintEpochDuration())
        trainer.append_task(tasks.PrintTrainingDuration())
        trainer.append_task(tasks.PrintTime(each_k_update=100))  # Profiling

        # Add stopping criteria
        trainer.append_task(stopping_criteria.MaxEpochStopping(args.max_epoch))
        early_stopping = stopping_criteria.EarlyStopping(lookahead_loss, lookahead=args.lookahead, eps=args.lookahead_eps, callback=save_improvement)
        trainer.append_task(early_stopping)

    with Timer("Compiling Theano graph"):
        trainer.build_theano_graph()

    if resuming:
        if not os.path.isdir(pjoin(experiment_path, 'training')):
            print("No 'training/' folder. Assuming it failed before"
                  " the end of the first epoch. Starting a new training.")
        else:
            with Timer("Loading"):
                trainer.load(experiment_path)

    with Timer("Training"):
        trainer.train()
コード例 #10
0
def test_simple_convnade():
    nb_kernels = 8
    kernel_shape = (2, 2)
    hidden_activation = "sigmoid"
    use_mask_as_input = True
    batch_size = 1024
    ordering_seed = 1234
    max_epoch = 3
    nb_orderings = 1

    print("Will train Convoluational Deep NADE for a total of {0} epochs.".
          format(max_epoch))

    with Timer("Loading/processing binarized MNIST"):
        trainset, validset, testset = load_binarized_mnist()

        # Extract the center patch (4x4 pixels) of each image.
        indices_to_keep = [
            348, 349, 350, 351, 376, 377, 378, 379, 404, 405, 406, 407, 432,
            433, 434, 435
        ]

        trainset = Dataset(trainset.inputs.get_value()[:, indices_to_keep],
                           trainset.inputs.get_value()[:, indices_to_keep],
                           name="trainset")
        validset = Dataset(validset.inputs.get_value()[:, indices_to_keep],
                           validset.inputs.get_value()[:, indices_to_keep],
                           name="validset")
        testset = Dataset(testset.inputs.get_value()[:, indices_to_keep],
                          testset.inputs.get_value()[:, indices_to_keep],
                          name="testset")

        image_shape = (4, 4)
        nb_channels = 1

    with Timer("Building model"):
        builder = DeepConvNADEBuilder(image_shape=image_shape,
                                      nb_channels=nb_channels,
                                      use_mask_as_input=use_mask_as_input)

        convnet_blueprint = "64@2x2(valid) -> 1@2x2(full)"
        fullnet_blueprint = "5 -> 16"
        print("Convnet:", convnet_blueprint)
        print("Fullnet:", fullnet_blueprint)
        builder.build_convnet_from_blueprint(convnet_blueprint)
        builder.build_fullnet_from_blueprint(fullnet_blueprint)

        model = builder.build()
        model.initialize()  # By default, uniform initialization.

    with Timer("Building optimizer"):
        loss = BinaryCrossEntropyEstimateWithAutoRegressiveMask(
            model, trainset)

        optimizer = SGD(loss=loss)
        optimizer.append_direction_modifier(ConstantLearningRate(0.001))

    with Timer("Building trainer"):
        batch_scheduler = MiniBatchSchedulerWithAutoregressiveMask(
            trainset, batch_size)

        trainer = Trainer(optimizer, batch_scheduler)

        trainer.append_task(stopping_criteria.MaxEpochStopping(max_epoch))

        # Print time for one epoch
        trainer.append_task(tasks.PrintEpochDuration())
        trainer.append_task(tasks.PrintTrainingDuration())

        # Log training error
        loss_monitor = views.MonitorVariable(loss.loss)
        avg_loss = tasks.AveragePerEpoch(loss_monitor)
        accum = tasks.Accumulator(loss_monitor)
        logger = tasks.Logger(loss_monitor, avg_loss)
        trainer.append_task(logger, avg_loss, accum)

        # Print average training loss.
        trainer.append_task(
            tasks.Print("Avg. training loss:     : {}", avg_loss))

        # Print NLL mean/stderror.
        nll = views.LossView(
            loss=BinaryCrossEntropyEstimateWithAutoRegressiveMask(
                model, validset),
            batch_scheduler=MiniBatchSchedulerWithAutoregressiveMask(
                validset, batch_size=len(validset)))
        trainer.append_task(
            tasks.Print("Validset - NLL          : {0:.2f} ± {1:.2f}",
                        nll.mean, nll.stderror))

        trainer.build_theano_graph()

    with Timer("Training"):
        trainer.train()

    with Timer("Checking the probs for all possible inputs sum to 1"):
        rng = np.random.RandomState(ordering_seed)
        D = np.prod(image_shape)
        inputs = cartesian([[0, 1]] * int(D), dtype=np.float32)
        ordering = np.arange(D, dtype=np.int32)
        rng.shuffle(ordering)

        symb_input = T.vector("input")
        symb_input.tag.test_value = inputs[-len(inputs) // 4]
        symb_ordering = T.ivector("ordering")
        symb_ordering.tag.test_value = ordering
        nll_of_x_given_o = theano.function([symb_input, symb_ordering],
                                           model.nll_of_x_given_o(
                                               symb_input, symb_ordering),
                                           name="nll_of_x_given_o")
        #theano.printing.pydotprint(nll_of_x_given_o, '{0}_nll_of_x_given_o_{1}'.format(model.__class__.__name__, theano.config.device), with_ids=True)

        for i in range(nb_orderings):
            print("Ordering:", ordering)
            ordering = np.arange(D, dtype=np.int32)
            rng.shuffle(ordering)

            nlls = []
            for no, input in enumerate(inputs):
                print("{}/{}".format(no, len(inputs)), end='\r')
                nlls.append(nll_of_x_given_o(input, ordering))

            print("{}/{} Done".format(len(inputs), len(inputs)))

            p_x = np.exp(np.logaddexp.reduce(-np.array(nlls)))
            print("Sum of p(x) for all x:", p_x)
            assert_almost_equal(p_x, 1., decimal=5)
コード例 #11
0
def main():
    parser = build_parser()
    args = parser.parse_args()
    print(args)

    # Get experiment folder
    experiment_path = args.name
    if not os.path.isdir(experiment_path):
        # If not a directory, it must be the name of the experiment.
        experiment_path = pjoin(".", "experiments", args.name)

    if not os.path.isdir(experiment_path):
        parser.error('Cannot find experiment: {0}!'.format(args.name))

    # Load experiments hyperparameters
    try:
        hyperparams = smartutils.load_dict_from_json_file(
            pjoin(experiment_path, "hyperparams.json"))
    except FileNotFoundError:
        hyperparams = smartutils.load_dict_from_json_file(
            pjoin(experiment_path, "..", "hyperparams.json"))

    # Use this for hyperparams added in a new version, but nonexistent from older versions
    retrocompatibility_defaults = {
        'feed_previous_direction': False,
        'predict_offset': False,
        'normalize': False,
        'keep_step_size': False,
        'sort_streamlines': False,
        'use_layer_normalization': False,
        'drop_prob': 0.,
        'use_zoneout': False
    }
    for new_hyperparams, default_value in retrocompatibility_defaults.items():
        if new_hyperparams not in hyperparams:
            hyperparams[new_hyperparams] = default_value

    with Timer("Loading dataset", newline=True):
        volume_manager = VolumeManager()
        dataset = datasets.load_tractography_dataset(
            args.subjects,
            volume_manager,
            name="dataset",
            use_sh_coeffs=hyperparams['use_sh_coeffs'])
        print("Dataset size:", len(dataset))

    with Timer("Loading model"):
        model = None
        if hyperparams['model'] == 'gru_regression':
            from learn2track.models import GRU_Regression
            model = GRU_Regression.create(experiment_path,
                                          volume_manager=volume_manager)
        elif hyperparams['model'] == 'gru_gaussian':
            from learn2track.models import GRU_Gaussian
            model = GRU_Gaussian.create(experiment_path,
                                        volume_manager=volume_manager)
        elif hyperparams['model'] == 'gru_mixture':
            from learn2track.models import GRU_Mixture
            model = GRU_Mixture.create(experiment_path,
                                       volume_manager=volume_manager)
        elif hyperparams['model'] == 'gru_multistep':
            from learn2track.models import GRU_Multistep_Gaussian
            model = GRU_Multistep_Gaussian.create(
                experiment_path, volume_manager=volume_manager)
            model.k = 1
            model.m = 1
        elif hyperparams['model'] == 'ffnn_regression':
            from learn2track.models import FFNN_Regression
            model = FFNN_Regression.create(experiment_path,
                                           volume_manager=volume_manager)
        else:
            raise NameError("Unknown model: {}".format(hyperparams['model']))
        model.drop_prob = 0.  # Make sure dropout/zoneout is not used when testing

    with Timer("Building evaluation function"):
        # Override K for gru_multistep
        if 'k' in hyperparams:
            hyperparams['k'] = 1

        batch_scheduler = batch_scheduler_factory(
            hyperparams,
            dataset,
            train_mode=False,
            batch_size_override=args.batch_size)
        loss = loss_factory(hyperparams,
                            model,
                            dataset,
                            loss_type=args.loss_type)
        l2_error = views.LossView(loss=loss, batch_scheduler=batch_scheduler)

    with Timer("Evaluating...", newline=True):
        results_file = pjoin(experiment_path, "results.json")
        results = {}
        if os.path.isfile(results_file) and not args.force:
            print(
                "Loading saved results... (use --force to re-run evaluation)")
            results = smartutils.load_dict_from_json_file(results_file)

        tag = ""
        if args.loss_type == 'expected_value' or hyperparams[
                'model'] == 'gru_regression':
            tag = "_EV_L2_error"
        elif args.loss_type == 'maximum_component':
            tag = "_MC_L2_error"
        elif hyperparams['model'] in [
                'gru_gaussian', 'gru_mixture', 'gru_multistep'
        ]:
            tag = "_NLL"

        entry = args.dataset_name + tag

        if entry not in results or args.force:
            with Timer("Evaluating {}".format(entry)):
                dummy_status = Status()  # Forces recomputing results
                results[entry] = {
                    'mean': float(l2_error.mean.view(dummy_status)),
                    'stderror': float(l2_error.stderror.view(dummy_status))
                }
                smartutils.save_dict_to_json_file(
                    results_file, results)  # Update results file.

        print("{}: {:.4f} ± {:.4f}".format(entry, results[entry]['mean'],
                                           results[entry]['stderror']))
コード例 #12
0
def main():
    parser = build_argparser()
    args = parser.parse_args()
    print(args)
    print("Using Theano v.{}".format(theano.version.short_version))

    hyperparams_to_exclude = ['max_epoch', 'force', 'name', 'view']
    # Use this for hyperparams added in a new version, but nonexistent from older versions
    retrocompatibility_defaults = {'use_layer_normalization': False}
    experiment_path, hyperparams, resuming = utils.maybe_create_experiment_folder(
        args,
        exclude=hyperparams_to_exclude,
        retrocompatibility_defaults=retrocompatibility_defaults)

    # Log the command currently running.
    with open(pjoin(experiment_path, 'cmd.txt'), 'a') as f:
        f.write(" ".join(sys.argv) + "\n")

    print("Resuming:" if resuming else "Creating:", experiment_path)

    with Timer("Loading dataset", newline=True):
        trainset_volume_manager = VolumeManager()
        validset_volume_manager = VolumeManager()
        trainset = datasets.load_mask_classifier_dataset(
            args.train_subjects,
            trainset_volume_manager,
            name="trainset",
            use_sh_coeffs=args.use_sh_coeffs)
        validset = datasets.load_mask_classifier_dataset(
            args.valid_subjects,
            validset_volume_manager,
            name="validset",
            use_sh_coeffs=args.use_sh_coeffs)
        print("Dataset sizes:", len(trainset), " |", len(validset))

        batch_scheduler = MaskClassifierBatchScheduler(
            trainset, hyperparams['batch_size'], seed=hyperparams['seed'])
        print("An epoch will be composed of {} updates.".format(
            batch_scheduler.nb_updates_per_epoch))
        print(trainset_volume_manager.data_dimension, args.hidden_sizes,
              batch_scheduler.target_size)

    with Timer("Creating model"):
        input_size = trainset_volume_manager.data_dimension

        model = FFNN_Classification(trainset_volume_manager, input_size,
                                    hyperparams['hidden_sizes'])
        model.initialize(
            weigths_initializer_factory(args.weights_initialization,
                                        seed=args.initialization_seed))

    with Timer("Building optimizer"):
        loss = BinaryCrossEntropy(model, trainset)

        if args.clip_gradient is not None:
            loss.append_gradient_modifier(
                DirectionClipping(threshold=args.clip_gradient))

        optimizer = optimizer_factory(hyperparams, loss)

    with Timer("Building trainer"):
        trainer = Trainer(optimizer, batch_scheduler)

        # Log training error
        loss_monitor = views.MonitorVariable(loss.loss)
        avg_loss = tasks.AveragePerEpoch(loss_monitor)
        trainer.append_task(avg_loss)

        # Print average training loss.
        trainer.append_task(
            tasks.Print("Avg. training loss:         : {}", avg_loss))

        # HACK: To make sure all subjects in the volume_manager are used in a batch, we have to split the trainset/validset in 2 volume managers
        model.volume_manager = validset_volume_manager
        valid_loss = BinaryCrossEntropy(model, validset)
        valid_batch_scheduler = MaskClassifierBatchScheduler(
            validset, hyperparams['batch_size'], seed=hyperparams['seed'])

        valid_error = views.LossView(loss=valid_loss,
                                     batch_scheduler=valid_batch_scheduler)
        trainer.append_task(
            tasks.Print("Validset - Error        : {0:.2f} | {1:.2f}",
                        valid_error.sum, valid_error.mean))

        # HACK: Restore trainset volume manager
        model.volume_manager = trainset_volume_manager

        lookahead_loss = valid_error.sum

        direction_norm = views.MonitorVariable(
            T.sqrt(sum(map(lambda d: T.sqr(d).sum(),
                           loss.gradients.values()))))
        # trainer.append_task(tasks.Print("||d|| : {0:.4f}", direction_norm))

        # logger = tasks.Logger(train_error.mean, valid_error.mean, valid_error.sum, direction_norm)
        logger = tasks.Logger(valid_error.mean, valid_error.sum,
                              direction_norm)
        trainer.append_task(logger)

        # Callback function to stop training if NaN is detected.
        def detect_nan(obj, status):
            if np.isnan(model.parameters[0].get_value().sum()):
                print("NaN detected! Stopping training now.")
                sys.exit()

        trainer.append_task(tasks.Callback(detect_nan, each_k_update=1))

        # Callback function to save training progression.
        def save_training(obj, status):
            trainer.save(experiment_path)

        trainer.append_task(tasks.Callback(save_training))

        # Early stopping with a callback for saving every time model improves.
        def save_improvement(obj, status):
            """ Save best model and training progression. """
            if np.isnan(model.parameters[0].get_value().sum()):
                print("NaN detected! Not saving the model. Crashing now.")
                sys.exit()

            print("*** Best epoch: {0} ***\n".format(obj.best_epoch))
            model.save(experiment_path)

        # Print time for one epoch
        trainer.append_task(tasks.PrintEpochDuration())
        trainer.append_task(tasks.PrintTrainingDuration())
        trainer.append_task(tasks.PrintTime(each_k_update=100))  # Profiling

        # Add stopping criteria
        trainer.append_task(stopping_criteria.MaxEpochStopping(args.max_epoch))
        early_stopping = stopping_criteria.EarlyStopping(
            lookahead_loss,
            lookahead=args.lookahead,
            eps=args.lookahead_eps,
            callback=save_improvement)
        trainer.append_task(early_stopping)

    with Timer("Compiling Theano graph"):
        trainer.build_theano_graph()

    if resuming:
        if not os.path.isdir(pjoin(experiment_path, 'training')):
            print("No 'training/' folder. Assuming it failed before"
                  " the end of the first epoch. Starting a new training.")
        else:
            with Timer("Loading"):
                trainer.load(experiment_path)

    with Timer("Training"):
        trainer.train()