Exemple #1
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def run(train, test):
    init = Gaussian(scale=0.01)
    layers = [
        Conv((3, 3, 128),
             init=init,
             activation=Rectlin(),
             strides=dict(str_h=1, str_w=2)),
        Conv((3, 3, 256), init=init, batch_norm=True, activation=Rectlin()),
        Pooling(2, strides=2),
        Conv((2, 2, 512), init=init, batch_norm=True, activation=Rectlin()),
        DeepBiRNN(256,
                  init=init,
                  activation=Rectlin(),
                  reset_cells=True,
                  depth=3),
        RecurrentLast(),
        Affine(32, init=init, batch_norm=True, activation=Rectlin()),
        Affine(nout=common['nclasses'], init=init, activation=Softmax())
    ]

    model = Model(layers=layers)
    opt = Adadelta()
    metric = Misclassification()
    callbacks = Callbacks(model,
                          eval_set=test,
                          metric=metric,
                          **args.callback_args)
    cost = GeneralizedCost(costfunc=CrossEntropyBinary())

    model.fit(train,
              optimizer=opt,
              num_epochs=args.epochs,
              cost=cost,
              callbacks=callbacks)
    return model
Exemple #2
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def create_network():
    init = GlorotUniform()
    layers = [
        Conv((3, 3, 128),
             init=init,
             activation=Rectlin(),
             strides=dict(str_h=1, str_w=2)),
        Conv((3, 3, 256), init=init, batch_norm=True, activation=Rectlin()),
        Pooling(2, strides=2),
        Conv((2, 2, 512), init=init, batch_norm=True, activation=Rectlin()),
        DeepBiRNN(256,
                  init=init,
                  activation=Rectlin(),
                  reset_cells=True,
                  depth=3),
        RecurrentLast(),
        Affine(32, init=init, batch_norm=True, activation=Rectlin()),
        Affine(nout=2, init=init, activation=Softmax())
    ]

    return Model(layers=layers), GeneralizedCost(costfunc=CrossEntropyBinary())
Exemple #3
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        layers = [
            LSTM(hidden,
                 init,
                 activation=Logistic(),
                 gate_activation=Tanh(),
                 reset_cells=False),
            Affine(train_set.nfeatures, init, bias=init, activation=Identity())
        ]
    else:
        layers = [
            LSTM(hidden,
                 init,
                 activation=Logistic(),
                 gate_activation=Tanh(),
                 reset_cells=True),
            RecurrentLast(),
            Affine(train_set.nfeatures, init, bias=init, activation=Identity())
        ]

    model = Model(layers=layers)
    cost = GeneralizedCost(MeanSquared())
    optimizer = RMSProp(stochastic_round=args.rounding)

    callbacks = Callbacks(model, eval_set=valid_set, **args.callback_args)

    # fit model
    model.fit(train_set,
              optimizer=optimizer,
              num_epochs=args.epochs,
              cost=cost,
              callbacks=callbacks)
Exemple #4
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def load_sent_encoder(model_dict, expand_vocab=False, orig_vocab=None,
                      w2v_vocab=None, w2v_path=None, use_recur_last=False):
    """
    Custom function to load the model saved from skip-thought vector training
    and reconstruct another model just using the LUT and encoding layer for
    transfering sentence representations.

    Arguments:
        model_dict: saved s2v model dict
        expand_vocab: Bool to indicate if w2v vocab expansion should be attempted
        orig_vocab: If using expand_vocab, original vocabulary dict is needed for expansion
        w2v_vocab: If using expand_vocab, w2v vocab dict
        w2v_path: Path to trained w2v binary (GoogleNews)
        use_recur_last: If True a RecurrentLast layer is used as the final layer, if False
                        a RecurrentSum layer is used as the last layer of the returned model.
    """

    embed_dim = model_dict['model']['config']['embed_dim']
    model_train = Model(model_dict)

    # RecurrentLast should be used for semantic similarity evaluation
    if use_recur_last:
        last_layer = RecurrentLast()
    else:
        last_layer = RecurrentSum()

    if expand_vocab:
        assert orig_vocab and w2v_vocab, ("All vocabs and w2v_path " +
                                          "need to be specified when using expand_vocab")

        neon_logger.display("Computing vocab expansion regression...")
        # Build inverse word dictionary (word -> index)
        word_idict = dict()
        for kk, vv in orig_vocab.items():
            # Add 2 to the index to allow for padding and oov tokens as 0 and 1
            word_idict[vv + 2] = kk
        word_idict[0] = ''
        word_idict[1] = 'UNK'

        # Create dictionary of word -> vec
        orig_word_vecs = get_embeddings(model_train.layers.layer_dict['lookupTable'], word_idict)

        # Load GooleNews w2v weights
        w2v_W, w2v_dim, _ = get_google_word2vec_W(w2v_path, w2v_vocab)

        # Compute the expanded vocab lookup table from a linear mapping of
        # words2vec into RNN word space
        init_embed = compute_vocab_expansion(orig_word_vecs, w2v_W, w2v_vocab, word_idict)

        init_embed_dev = model_train.be.array(init_embed)
        w2v_vocab_size = len(w2v_vocab)

        table = LookupTable(vocab_size=w2v_vocab_size, embedding_dim=embed_dim,
                            init=init_embed_dev, pad_idx=0)

        model = Model(layers=[table,
                              model_train.layers.layer_dict['encoder'],
                              last_layer])

    else:
        model = Model(layers=[model_train.layers.layer_dict['lookupTable'],
                              model_train.layers.layer_dict['encoder'],
                              last_layer])
    return model
Exemple #5
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def main():
    parser = NeonArgparser(__doc__)
    args = parser.parse_args(gen_be=False)

    #mat_data = sio.loadmat('../data/timeseries/02_timeseries.mat')

    #ts = V1TimeSeries(mat_data['timeseries'], mat_data['stim'], binning=10)

    seq_len = 30
    hidden = 20

    be = gen_backend(**extract_valid_args(args, gen_backend))

    kohn = KohnV1Dataset(path='../tmp/')
    kohn.gen_iterators(seq_len)
    import pdb; pdb.set_trace()
    train_spike_set = V1IteratorSequence(ts.train, seq_len, return_sequences=False)
    valid_spike_set = V1IteratorSequence(ts.test, seq_len, return_sequences=False)

    init = GlorotUniform()

    # dataset = MNIST(path=args.data_dir)
    # (X_train, y_train), (X_test, y_test), nclass = dataset.load_data()
    # train_set = ArrayIterator([X_train, X_train], y_train, nclass=nclass, lshape=(1, 28, 28))
    # valid_set = ArrayIterator([X_test, X_test], y_test, nclass=nclass, lshape=(1, 28, 28))

    # # weight initialization
    # init_norm = Gaussian(loc=0.0, scale=0.01)

    # # initialize model
    # path1 = Sequential(layers=[Affine(nout=100, init=init_norm, activation=Rectlin()),
    #                            Affine(nout=100, init=init_norm, activation=Rectlin())])

    # path2 = Sequential(layers=[Affine(nout=100, init=init_norm, activation=Rectlin()),
    #                            Affine(nout=100, init=init_norm, activation=Rectlin())])

    # layers = [MergeMultistream(layers=[path1, path2], merge="stack"),
    #           Affine(nout=10, init=init_norm, activation=Logistic(shortcut=True))]

    spike_rnn_path = Sequential( layers = [

        LSTM(hidden, init, activation=Logistic(),
            gate_activation=Logistic(), reset_cells=False),

        Dropout(keep=0.5),

         LSTM(hidden, init, activation=Logistic(),
             gate_activation=Logistic(), reset_cells=False),

        #Dropout(keep=0.85),

        RecurrentLast(),

        Affine(train_set.nfeatures, init, bias=init, activation=Identity(), name='spike_in')])

    stim_rnn_path = Sequential( layers = [

        LSTM(hidden, init, activation=Logistic(),
            gate_activation=Logistic(), reset_cells=False),

        Dropout(keep=0.5),

        RecurrentLast(),
        Affine(1, init, bias=init, activation=Identity(), name='stim')])

    layers = [
            MergeMultiStream(
                layers = [
                    spike_rnn_path,
                    stim_rnn_path],
                merge="stack"),

            Affine(train_set.nfeatures, init, bias=init, activation=Identity(), name='spike_out'),

            Round()
            ]

    model = Model(layers=layers)

    sched = ExpSchedule(decay=0.7)

    # cost = GeneralizedCost(SumSquared())
    cost = GeneralizedCost(MeanSquared())

    optimizer_two = RMSProp(stochastic_round=args.rounding)
    optimizer_one = GradientDescentMomentum(learning_rate=0.1, momentum_coef=0.9, schedule=sched)

    opt = MultiOptimizer({'default': optimizer_one,
                          'Bias': optimizer_two,
                          'special_linear': optimizer_two})

    callbacks = Callbacks(model, eval_set=valid_set, **args.callback_args)
    callbacks.add_hist_callback(filter_key = ['W'])
    #callbacks.add_callback(MetricCallback(eval_set=valid_set, metric=FractionExplainedVariance(), epoch_freq=args.eval_freq))
    #callbacks.add_callback(MetricCallback(eval_set=valid_set,metric=Accuracy(),  epoch_freq=args.eval_freq))

    model.fit(train_set,
              optimizer=opt,
              num_epochs=args.epochs,
              cost=cost,
              callbacks=callbacks)

    train_output = model.get_outputs(
    train_set).reshape(-1, train_set.nfeatures)
    valid_output = model.get_outputs(
    valid_set).reshape(-1, valid_set.nfeatures)
    train_target = train_set.y_series
    valid_target = valid_set.y_series

    tfev = fev(train_output, train_target, train_set.mean)
    vfev = fev(valid_output, valid_target, valid_set.mean)

    neon_logger.display('Train FEV: %g, Valid FEV:  %g' % (tfev, vfev))
    # neon_logger.display('Train Mean: %g, Valid Mean:  %g' % (train_set.mean, valid_set.mean))

    plt.figure()
    plt.plot(train_output[:, 0], train_output[
        :, 1], 'bo', label='prediction')
    plt.plot(train_target[:, 0], train_target[:, 1], 'r.', label='target')
    plt.legend()
    plt.title('Neon on training set')
    plt.savefig('neon_series_training_output.png')

    plt.figure()
    plt.plot(valid_output[:, 0], valid_output[
        :, 1], 'bo', label='prediction')
    plt.plot(valid_target[:, 0], valid_target[:, 1], 'r.', label='target')
    plt.legend()
    plt.title('Neon on validation set')
    plt.savefig('neon_series_validation_output.png')