Exemple #1
0
def main_train(epochs, batchsize, solution="", sparse_penalty=0, sparsityTarget=0, sparsityTargetPenalty=0):

    # Experiment specific arguments
    conf_dataset = {
        "dataset": "avicenna",
        "expname": "dummy",  # Used to create the submission file
        "transfer": True,
        "normalize": True,  # (Default = True)
        "normalize_on_the_fly": False,  # (Default = False)
        "randomize_valid": True,  # (Default = True)
        "randomize_test": True,  # (Default = True)
        "saving_rate": 0,  # (Default = 0)
        "savedir": "./outputs",
    }

    # First layer = PCA-75 whiten
    pca_layer = {
        "name": "1st-PCA",
        "num_components": 75,
        "min_variance": -50,
        "whiten": True,
        "pca_class": "CovEigPCA",
        # Training properties
        "proba": [1, 0, 0],
        "savedir": "./outputs",
    }

    # Load the dataset
    data = utils.load_data(conf_dataset)

    if conf_dataset["transfer"]:
        # Data for the ALC proxy
        label = data[3]
        data = data[:3]

    # First layer : train or load a PCA
    pca = create_pca(conf_dataset, pca_layer, data, model=pca_layer["name"])
    data = [utils.sharedX(pca.function()(set.get_value(borrow=True)), borrow=True) for set in data]
    """
    if conf_dataset['transfer']:
        data_train, label_train = utils.filter_labels(data[0], label)
      
        alc = embed.score(data_train, label_train)
        print '... resulting ALC on train (for PCA) is', alc
    """

    nvis = utils.get_constant(data[0].shape[1]).item()

    conf = {
        "corruption_level": 0.1,
        "nhid": 200,
        "nvis": nvis,
        "anneal_start": 100,
        "base_lr": 0.001,
        "tied_weights": True,
        "act_enc": "sigmoid",
        "act_dec": None,
        #'lr_hb': 0.10,
        #'lr_vb': 0.10,
        "tied_weights": True,
        "solution": solution,
        "sparse_penalty": sparse_penalty,
        "sparsityTarget": sparsityTarget,
        "sparsityTargetPenalty": sparsityTargetPenalty,
        "irange": 0,
    }

    # A symbolic input representing your minibatch.
    minibatch = tensor.matrix()

    # Allocate a denoising autoencoder with binomial noise corruption.
    corruptor = GaussianCorruptor(conf["corruption_level"])
    da = DenoisingAutoencoder(
        corruptor,
        conf["nvis"],
        conf["nhid"],
        conf["act_enc"],
        conf["act_dec"],
        conf["tied_weights"],
        conf["solution"],
        conf["sparse_penalty"],
        conf["sparsityTarget"],
        conf["sparsityTargetPenalty"],
    )

    # Allocate an optimizer, which tells us how to update our model.
    # TODO: build the cost another way
    cost = SquaredError(da)(minibatch, da.reconstruct(minibatch)).mean()
    trainer = SGDOptimizer(da, conf["base_lr"], conf["anneal_start"])
    updates = trainer.cost_updates(cost)

    # Finally, build a Theano function out of all this.
    train_fn = theano.function([minibatch], cost, updates=updates)

    # Suppose we want minibatches of size 10
    proba = utils.getboth(conf, pca_layer, "proba")
    iterator = BatchIterator(data, proba, batchsize)

    # Here's a manual training loop. I hope to have some classes that
    # automate this a litle bit.
    final_cost = 0
    for epoch in xrange(epochs):
        c = []
        for minibatch_data in iterator:
            minibatch_err = train_fn(minibatch_data)
            c.append(minibatch_err)
        final_cost = numpy.mean(c)
        print "epoch %d, cost : %f" % (epoch, final_cost)

    print "############################## Fin de l'experience ############################"
    print "Calcul de l'ALC : "
    if conf_dataset["transfer"]:
        data_train, label_train = utils.filter_labels(data[0], label)
        alc = embed.score(data_train, label_train)

        print "Solution : ", solution
        print "sparse_penalty = ", sparse_penalty
        print "sparsityTarget = ", sparsityTarget
        print "sparsityTargetPenalty = ", sparsityTargetPenalty
        print "Final denoising error is : ", final_cost
        print "... resulting ALC on train is", alc
        return (alc, final_cost)
Exemple #2
0
            proxy_cost,
            updates=updates,
            name='train_fn')

    # Manual training loop,
    # copy/pasted from create_ae
    print '... training layer:', clsname
    start_time = time.clock()
    proba = utils.getboth(layer, conf, 'proba')
    iterator = BatchIterator(data, proba, layer['batch_size'])
    saving_counter = 0
    saving_rate = utils.getboth(layer, conf, 'saving_rate', 0)

    # For ALC
    if label is not None:
        data_train, label_train = utils.filter_labels(data[0], label)

    for epoch in xrange(layer['epochs']):
        c = []
        batch_time = time.clock()
        for minibatch_data in iterator:
            c.append(train_fn(minibatch_data))

        # Print time & cost
        train_time = time.clock() - batch_time
        print '... training epoch %d, time spent (min) %f, cost' % (
                epoch, train_time / 60.), numpy.mean(c)

        # Saving intermediate models
        if saving_rate != 0:
            saving_counter += 1