예제 #1
0
def train_lstm(
        dim_proj=None,
        xdim=None,
        ydim=None,
        patience=10,  # Number of epoch to wait before early stop if no progress
        n_epochs=500,  # The maximum number of epoch to run
        decay_c=0.,  # Weight decay for the classifier applied to the U weights.
        lrate=0.001,  # Learning rate for sgd (not used for adadelta and rmsprop)
        # n_words=10000,  # Vocabulary size
    optimizer=adadelta,  # sgd, adadelta and rmsprop available, sgd very hard to use, not recommanded (probably need momentum and decaying learning rate).
        encoder='lstm',  # TODO: can be removed must be lstm.
        trainpath='../data/cv/',
        trainlist='../cvlist/JK-ch-1234-songwise.txt',
        validset='../data/cv/C-ch-songwise.mat',
        dumppath='../model/blstmrnn_model.npz',  # The best model will be saved there
        batch_size=100,  # The batch size during training.

        # Parameter for extra option
    noise_std=0.,
        earlystop=True,
        dropout=True,  # if False slightly faster, but worst test error
        # This frequently need a bigger model.
    reload_model=None,  # Path to a saved model we want to start from.
):

    # Model options
    model_options = locals().copy()
    print "model options", model_options

    print 'Loading data'
    # the dateset is organized as:
    # X - n_songs * n_timesteps * dim_proj (dim_proj = 24 for chromagram based dataset)
    # y - n_songs * n_timesteps * 1
    train, valid = load_data_song(trainpath=trainpath,
                                  trainlist=trainlist,
                                  validset=validset)

    print 'data loaded'

    model_options['xdim'] = xdim
    model_options['dim_proj'] = dim_proj
    model_options['ydim'] = ydim

    print 'Building model'
    # This create the initial parameters as numpy ndarrays.
    # Dict name (string) -> numpy ndarray
    params = init_params(model_options)

    if reload_model:
        load_params('lstm_model.npz', params)

    # This create Theano Shared Variable from the parameters.
    # Dict name (string) -> Theano Tensor Shared Variable
    # params and tparams have different copy of the weights.
    tparams = init_tparams(params)

    # use_noise is for dropout
    # the model takes input of:
    # x -- n_timesteps * dim_proj * n_samples (in a simpler case, n_samples = 1 in ctc)
    # y -- n_timesteps * 1 * n_samples (in a simpler case, n_samples = 1 in ctc)
    (use_noise, x, y, f_pred_prob, f_pred,
     cost) = build_model(tparams, model_options)

    if decay_c > 0.:
        decay_c = theano.shared(numpy_floatX(decay_c), name='decay_c')
        weight_decay = 0.
        weight_decay += (tparams['U']**2).sum()
        weight_decay *= decay_c
        cost += weight_decay

    f_cost = theano.function([x, y], cost, name='f_cost')

    grads = T.grad(cost, wrt=tparams.values())
    f_grad = theano.function([x, y], grads, name='f_grad')

    lr = T.scalar(name='lr')
    f_grad_shared, f_update = optimizer(lr, tparams, grads, x, y, cost)

    print 'Optimization'

    print "%d train examples" % len(train[0])
    print "%d valid examples" % len(valid[0])

    best_validation_loss = numpy.inf
    best_p = None
    # 6000 is a scaling factor assuming every track contains 5000 frames on average
    n_train_batches = len(
        train[0]) * 5000 / batch_size / 10  # 10 is a scaling factor
    patience = min(10 * n_train_batches,
                   15000)  # look as this many examples regardless
    patience_increase = 1.3  # wait this much longer when a new best is found
    done_looping = False
    improvement_threshold = 0.996  # a relative improvement of this much is
    validation_frequency = 100  # note here we manually set the validation freq
    training_history = []
    iter = 0
    best_iter = 0
    start_time = time.time()
    for epoch in xrange(n_epochs):
        if earlystop and done_looping:
            print 'early-stopping'
            break
        n_samples = 0

        # Get random sample a piece of length batch_size from a song
        idx0 = numpy.random.randint(0, len(train[0]))

        batch_size_ = batch_size
        while len(train[0][idx0]) <= batch_size_:
            batch_size_ = batch_size_ / 2

        idx1 = numpy.random.randint(0,
                                    len(train[0][idx0]) -
                                    batch_size_)  # 500 in our case

        iter += 1
        use_noise.set_value(1.)

        # Select the random examples for this minibatch
        x = train[0][idx0][idx1:idx1 + batch_size_]
        y = train[1][idx0][idx1:idx1 + batch_size_]

        # Get the data in numpy.ndarray format
        # This swap the axis!
        # Return something of shape (minibatch maxlen, n samples)
        n_samples += 1

        cost = f_grad_shared(x, y)
        f_update(lrate)

        if numpy.mod(iter, validation_frequency) == 0:
            use_noise.set_value(0.)

            this_validation_loss = pred_error(f_pred, valid)
            training_history.append([iter, this_validation_loss])
            print('epoch %i, validation error %f %%' %
                  (epoch, this_validation_loss * 100.))
            print('iter = %d' % iter)
            print('patience = %d' % patience)

            if this_validation_loss < best_validation_loss:
                #improve patience if loss improvement is good enough
                if (this_validation_loss <
                        best_validation_loss * improvement_threshold):
                    patience = max(patience, iter * patience_increase)

                params = unzip(tparams)
                numpy.savez(dumppath,
                            training_history=training_history,
                            best_validation_loss=best_validation_loss,
                            **params)

                # save best validation score and iteration number
                best_validation_loss = this_validation_loss
                best_iter = iter
                print('best_validation_loss %f' % best_validation_loss)

        if patience <= iter:
            done_looping = True
            if earlystop:
                break

    end_time = time.time()
    # final save
    numpy.savez(dumppath,
                training_history=training_history,
                best_validation_loss=best_validation_loss,
                **params)

    print(('Optimization complete with best validation score of %f %%, '
           'obtained at iteration %i, ') %
          (best_validation_loss * 100., best_iter + 1))
    print >> sys.stderr, ('The fine tuning code for file ' +
                          os.path.split(__file__)[1] + ' ran for %.2fm' %
                          ((end_time - start_time) / 60.))
예제 #2
0
def train_lstm(
    dim_proj=None,
    xdim=None,
    ydim=None,
    patience=10,  # Number of epoch to wait before early stop if no progress
    max_epochs=500,  # The maximum number of epoch to run
    dispFreq=10,  # Display to stdout the training progress every N updates
    decay_c=0.,  # Weight decay for the classifier applied to the U weights.
    lrate=0.001,  # Learning rate for sgd (not used for adadelta and rmsprop)
    # n_words=10000,  # Vocabulary size
    optimizer=adadelta,  # sgd, adadelta and rmsprop available, sgd very hard to use, not recommanded (probably need momentum and decaying learning rate).
    encoder='lstm',  # TODO: can be removed must be lstm.
    dumppath='ctc_model.npz',  # The best model will be saved there
    validFreq=400,  # Compute the validation error after this number of update.
    saveFreq=1000,  # Save the parameters after every saveFreq updates
    maxlen=None,  # Sequence longer then this get ignored
    batch_size=100,  # The batch size during training.
    valid_batch_size=100,  # The batch size used for validation/test set.
    dataset=None,

    # Parameter for extra option
    noise_std=0.,
    use_dropout=True,  # if False slightly faster, but worst test error
    # This frequently need a bigger model.
    reload_model=None,  # Path to a saved model we want to start from.
    test_size=-1,  # If >0, we keep only this number of test example.
    scaling=1,
):

    # Model options
    model_options = locals().copy()
    print "model options", model_options

    print 'Loading data'
    # the dateset is organized as:
    # X - n_songs * n_timesteps * dim_proj (dim_proj = 24 for chromagram based dataset)
    # y - n_songs * n_timesteps * 1
    train, valid, test = load_data_song(dataset=dataset,
                                        valid_portion=0.1,
                                        test_portion=0.1)

    print 'data loaded'

    model_options['xdim'] = xdim
    model_options['dim_proj'] = dim_proj
    model_options['ydim'] = ydim

    print 'Building model'
    # This create the initial parameters as numpy ndarrays.
    # Dict name (string) -> numpy ndarray
    params = init_params(model_options)

    if reload_model:
        load_params('lstm_model.npz', params)

    # This create Theano Shared Variable from the parameters.
    # Dict name (string) -> Theano T Shared Variable
    # params and tparams have different copy of the weights.
    tparams = init_tparams(params)

    # use_noise is for dropout
    # the model takes input of:
    # x -- n_timesteps * dim_proj * n_samples (in a simpler case, n_samples = 1 in ctc)
    # y -- n_timesteps * 1 * n_samples (in a simpler case, n_samples = 1 in ctc)
    (use_noise, x, y, f_pred_prob, f_pred,
     cost) = build_model(tparams, model_options)

    if decay_c > 0.:
        decay_c = theano.shared(numpy_floatX(decay_c), name='decay_c')
        weight_decay = 0.
        weight_decay += (tparams['U']**2).sum()
        weight_decay *= decay_c
        cost += weight_decay

    f_cost = theano.function([x, y], cost, name='f_cost')

    grads = T.grad(cost, wrt=tparams.values())
    f_grad = theano.function([x, y], grads, name='f_grad')

    lr = T.scalar(name='lr')
    f_grad_shared, f_update = optimizer(lr, tparams, grads, x, y, cost)

    print 'Optimization'

    print "%d train examples" % len(train[0])
    print "%d valid examples" % len(valid[0])
    print "%d test examples" % len(test[0])

    history_errs = []
    best_p = None
    bad_count = 0

    uidx = 0  # the number of update done
    estop = False  # early stop
    start_time = time.time()
    try:
        for eidx in xrange(max_epochs):
            n_samples = 0

            # Get random sample a piece of length batch_size from a song
            idx0 = numpy.random.randint(0, len(train[0]))

            batch_size_ = batch_size
            while len(train[0][idx0]) <= batch_size_:
                batch_size_ = batch_size_ / 2

            idx1 = numpy.random.randint(0,
                                        len(train[0][idx0]) -
                                        batch_size_)  # 500 in our case

            uidx += 1
            use_noise.set_value(1.)

            # Select the random examples for this minibatch
            x = train[0][idx0][idx1:idx1 + batch_size_]
            y = train[1][idx0][idx1:idx1 + batch_size_]

            # Get the data in numpy.ndarray format
            # This swap the axis!
            # Return something of shape (minibatch maxlen, n samples)
            n_samples += 1

            cost = f_grad_shared(x, y)
            f_update(lrate)

            if numpy.isnan(cost) or numpy.isinf(cost):
                print 'NaN detected'
                return 1., 1., 1.

            if numpy.mod(uidx, dispFreq) == 0:
                print 'Epoch ', eidx, 'Update ', uidx, 'Cost ', cost

            if dumppath and numpy.mod(uidx, saveFreq) == 0:
                print 'Saving...',

                # save the best param set to date (best_p)
                if best_p is not None:
                    params = best_p
                else:
                    params = unzip(tparams)
                numpy.savez(dumppath, history_errs=history_errs, **params)
                # pkl.dump(model_options, open('%s.pkl' % dumppath, 'wb'), -1)
                print 'Done'

            if numpy.mod(uidx, validFreq) == 0:
                use_noise.set_value(0.)
                # train_err = pred_error(f_pred, train)
                valid_err = pred_error(f_pred, valid)
                # test_err = pred_error(f_pred, test)

                # history_errs.append([valid_err, test_err])
                history_errs.append([valid_err, 1])

                # save param only if the validation error is less than the history minimum
                if (uidx == 0
                        or valid_err <= numpy.array(history_errs)[:, 0].min()):

                    best_p = unzip(tparams)
                    bad_counter = 0

                # print ('Train ', train_err, 'Valid ', valid_err,
                # 'Test ', test_err)
                print('Valid ', valid_err)

                # early stopping
                if (len(history_errs) > patience and valid_err >=
                        numpy.array(history_errs)[:-patience, 0].min()):
                    bad_counter += 1
                    if bad_counter > patience:
                        print 'Early Stop!'
                        estop = True
                        break

            # print 'Seen %d samples' % n_samples

            if estop:
                break

    except KeyboardInterrupt:
        print "Training interupted"

    end_time = time.time()
    if best_p is not None:
        zipp(best_p, tparams)
    else:
        best_p = unzip(tparams)

    use_noise.set_value(0.)
    train_err = pred_error(f_pred, train)
    valid_err = pred_error(f_pred, valid)
    test_err = pred_error(f_pred, test)

    print 'Train ', train_err, 'Valid ', valid_err, 'Test ', test_err
    if dumppath:
        numpy.savez(dumppath,
                    train_err=train_err,
                    valid_err=valid_err,
                    test_err=test_err,
                    history_errs=history_errs,
                    **best_p)
    print 'The code run for %d epochs, with %f sec/epochs' % (
        (eidx + 1), (end_time - start_time) / (1. * (eidx + 1)))
    print >> sys.stderr, ('Training took %.1fs' % (end_time - start_time))
    return train_err, valid_err, test_err
예제 #3
0
def train_lstm(
    dim_proj=None,
    xdim=None,
    ydim=None,
    patience=10,  # Number of epoch to wait before early stop if no progress
    max_epochs=500,  # The maximum number of epoch to run
    dispFreq=10,  # Display to stdout the training progress every N updates
    decay_c=0.,  # Weight decay for the classifier applied to the U weights.
    lrate=0.001,  # Learning rate for sgd (not used for adadelta and rmsprop)
    # n_words=10000,  # Vocabulary size
    optimizer=adadelta,  # sgd, adadelta and rmsprop available, sgd very hard to use, not recommanded (probably need momentum and decaying learning rate).
    encoder='lstm',  # TODO: can be removed must be lstm.
    dumppath='bctc_model.npz',  # The best model will be saved there
    validFreq=5000,  # Compute the validation error after this number of update.
    saveFreq=10000,  # Save the parameters after every saveFreq updates
    maxlen=None,  # Sequence longer then this get ignored
    batch_size=100,  # The batch size during training.
    valid_batch_size=100,  # The batch size used for validation/test set.
    dataset=None,

    # Parameter for extra option
    noise_std=0.,
    use_dropout=True,  # if False slightly faster, but worst test error
                       # This frequently need a bigger model.
    reload_model=None,  # Path to a saved model we want to start from.
    test_size=-1,  # If >0, we keep only this number of test example.
    scaling=1,
):

    # Model options
    model_options = locals().copy()
    print "model options", model_options
    
    print 'Loading data'
    # the dateset is organized as:
    # X - n_songs * n_timesteps * dim_proj (dim_proj = 24 for chromagram based dataset)
    # y - n_songs * n_timesteps * 1
    train, valid, test = load_data_song(dataset=dataset, valid_portion=0.1, test_portion=0.1)
                                   
    print 'data loaded'
    
    model_options['xdim'] = xdim
    model_options['dim_proj'] = dim_proj
    model_options['ydim'] = ydim
    
    print 'Building model'
    # This create the initial parameters as numpy ndarrays.
    # Dict name (string) -> numpy ndarray
    params = init_params(model_options)

    if reload_model:
        load_params('lstm_model.npz', params)

    # This create Theano Shared Variable from the parameters.
    # Dict name (string) -> Theano Tensor Shared Variable
    # params and tparams have different copy of the weights.
    tparams = init_tparams(params)

    # use_noise is for dropout
    # the model takes input of:
    # x -- n_timesteps * dim_proj * n_samples (in a simpler case, n_samples = 1 in ctc)
    # y -- n_timesteps * 1 * n_samples (in a simpler case, n_samples = 1 in ctc)
    (use_noise, x,
     y, f_pred_prob, f_pred, cost) = build_model(tparams, model_options)

    if decay_c > 0.:
        decay_c = theano.shared(numpy_floatX(decay_c), name='decay_c')
        weight_decay = 0.
        weight_decay += (tparams['U'] ** 2).sum()
        weight_decay *= decay_c
        cost += weight_decay

    f_cost = theano.function([x, y], cost, name='f_cost')

    grads = T.grad(cost, wrt=tparams.values())
    f_grad = theano.function([x, y], grads, name='f_grad')

    lr = T.scalar(name='lr')
    f_grad_shared, f_update = optimizer(lr, tparams, grads,
                                        x, y, cost)

    print 'Optimization'

    print "%d train examples" % len(train[0])
    print "%d valid examples" % len(valid[0])
    print "%d test examples" % len(test[0])

    history_errs = []
    best_p = None
    bad_count = 0

    uidx = 0  # the number of update done
    estop = False  # early stop
    start_time = time.time()
    try:
        for eidx in xrange(max_epochs):
            n_samples = 0

            # Get random sample a piece of length batch_size from a song
            idx0 = numpy.random.randint(0,len(train[0]))
            
            batch_size_ = batch_size
            while len(train[0][idx0]) <= batch_size_:
                batch_size_ = batch_size_ / 2
                
            idx1 = numpy.random.randint(0,len(train[0][idx0])-batch_size_) # 500 in our case
            
            uidx += 1
            use_noise.set_value(1.)
            
            # Select the random examples for this minibatch
            x = train[0][idx0][idx1:idx1+batch_size_]
            y = train[1][idx0][idx1:idx1+batch_size_]
            
            # Get the data in numpy.ndarray format
            # This swap the axis!
            # Return something of shape (minibatch maxlen, n samples)
            n_samples += 1

            cost = f_grad_shared(x, y)
            f_update(lrate)

            # if numpy.isnan(cost) or numpy.isinf(cost):
                # print 'NaN detected'
                # return 1., 1., 1.

            if numpy.mod(uidx, dispFreq) == 0:
                print 'Epoch ', eidx, 'Update ', uidx, 'Cost ', cost

            if dumppath and numpy.mod(uidx, saveFreq) == 0:
                print 'Saving...',
                
                # save the best param set to date (best_p)
                if best_p is not None:
                    params = best_p
                else:
                    params = unzip(tparams)
                numpy.savez(dumppath, history_errs=history_errs, **params)
                # pkl.dump(model_options, open('%s.pkl' % dumppath, 'wb'), -1)
                print 'Done'

            if numpy.mod(uidx, validFreq) == 0:
                use_noise.set_value(0.)
                # train_err = pred_error(f_pred, train)
                valid_err = pred_error(f_pred, valid)
                # test_err = pred_error(f_pred, test)

                # history_errs.append([valid_err, test_err])
                history_errs.append([valid_err, 1])
                
                # save param only if the validation error is less than the history minimum
                if (uidx == 0 or
                    valid_err <= numpy.array(history_errs)[:,
                                                           0].min()):

                    best_p = unzip(tparams)
                    bad_counter = 0

                # print ('Train ', train_err, 'Valid ', valid_err,
                       # 'Test ', test_err)
                print ('Valid', valid_err)
                
                # early stopping
                if (len(history_errs) > patience and
                    valid_err >= numpy.array(history_errs)[:-patience,
                                                           0].min()):
                    bad_counter += 1
                    if bad_counter > patience:
                        print 'Early Stop!'
                        estop = True
                        break

            # print 'Seen %d samples' % n_samples

            if estop:
                break

    except KeyboardInterrupt:
        print "Training interupted"

    end_time = time.time()
    if best_p is not None:
        zipp(best_p, tparams)
    else:
        best_p = unzip(tparams)

    use_noise.set_value(0.)
    train_err = pred_error(f_pred, train)
    valid_err = pred_error(f_pred, valid)
    test_err = pred_error(f_pred, test)

    print 'Train ', train_err, 'Valid ', valid_err, 'Test ', test_err
    if dumppath:
        numpy.savez(dumppath, train_err=train_err,
                    valid_err=valid_err, test_err=test_err,
                    history_errs=history_errs, **best_p)
    print 'The code run for %d epochs, with %f sec/epochs' % (
        (eidx + 1), (end_time - start_time) / (1. * (eidx + 1)))
    print >> sys.stderr, ('Training took %.1fs' %
                          (end_time - start_time))
    return train_err, valid_err, test_err
예제 #4
0
def train_lstm(
    dim_proj=None,
    xdim=None,
    ydim=None,
    patience=10,  # Number of epoch to wait before early stop if no progress
    n_epochs=500,  # The maximum number of epoch to run
    decay_c=0.,  # Weight decay for the classifier applied to the U weights.
    lrate=0.001,  # Learning rate for sgd (not used for adadelta and rmsprop)
    # n_words=10000,  # Vocabulary size
    optimizer=adadelta,  # sgd, adadelta and rmsprop available, sgd very hard to use, not recommanded (probably need momentum and decaying learning rate).
    encoder='lstm',  # TODO: can be removed must be lstm.
    trainpath='../data/cv/',
    trainlist='../cvlist/JK-ch-1234-songwise.txt',
    validset='../data/cv/C-ch-songwise.mat',
    dumppath='../model/blstmrnn_model.npz',  # The best model will be saved there
    batch_size=100,  # The batch size during training.

    # Parameter for extra option
    noise_std=0.,
    earlystop=True,
    dropout=True,  # if False slightly faster, but worst test error
                       # This frequently need a bigger model.
    reload_model=None,  # Path to a saved model we want to start from.
):

    # Model options
    model_options = locals().copy()
    print "model options", model_options
    
    print 'Loading data'
    # the dateset is organized as:
    # X - n_songs * n_timesteps * dim_proj (dim_proj = 24 for chromagram based dataset)
    # y - n_songs * n_timesteps * 1
    train, valid = load_data_song(trainpath=trainpath,trainlist=trainlist,validset=validset)
                                   
    print 'data loaded'
    
    model_options['xdim'] = xdim
    model_options['dim_proj'] = dim_proj
    model_options['ydim'] = ydim
    
    print 'Building model'
    # This create the initial parameters as numpy ndarrays.
    # Dict name (string) -> numpy ndarray
    params = init_params(model_options)

    if reload_model:
        load_params('lstm_model.npz', params)

    # This create Theano Shared Variable from the parameters.
    # Dict name (string) -> Theano Tensor Shared Variable
    # params and tparams have different copy of the weights.
    tparams = init_tparams(params)

    # use_noise is for dropout
    # the model takes input of:
    # x -- n_timesteps * dim_proj * n_samples (in a simpler case, n_samples = 1 in ctc)
    # y -- n_timesteps * 1 * n_samples (in a simpler case, n_samples = 1 in ctc)
    (use_noise, x,
     y, f_pred_prob, f_pred, cost) = build_model(tparams, model_options)

    if decay_c > 0.:
        decay_c = theano.shared(numpy_floatX(decay_c), name='decay_c')
        weight_decay = 0.
        weight_decay += (tparams['U'] ** 2).sum()
        weight_decay *= decay_c
        cost += weight_decay

    f_cost = theano.function([x, y], cost, name='f_cost')

    grads = T.grad(cost, wrt=tparams.values())
    f_grad = theano.function([x, y], grads, name='f_grad')

    lr = T.scalar(name='lr')
    f_grad_shared, f_update = optimizer(lr, tparams, grads,
                                        x, y, cost)

    print 'Optimization'

    print "%d train examples" % len(train[0])
    print "%d valid examples" % len(valid[0])

    best_validation_loss = numpy.inf
    best_p = None    
    # 6000 is a scaling factor assuming every track contains 5000 frames on average
    n_train_batches = len(train[0]) * 5000 / batch_size / 10 # 10 is a scaling factor
    patience = min(10 * n_train_batches,15000)  # look as this many examples regardless
    patience_increase = 1.3    # wait this much longer when a new best is found
    done_looping = False
    improvement_threshold = 0.996  # a relative improvement of this much is  
    validation_frequency = 100 # note here we manually set the validation freq
    training_history = []
    iter = 0
    best_iter = 0
    start_time = time.time()
    # SP is a (songidx, pos) dictionary ordered by class label. It has ydim entries
    SP = balanced(ydim,train[1])
    
    classorder = numpy.random.permutation(ydim)
    for epoch in xrange(n_epochs):
        if earlystop and done_looping:
            print 'early-stopping'
            break
        # generate a random order of a balanced class distribution
        #print 'epoch',epoch
        classidx = epoch % ydim
        #print 'classidx', classidx
        if classidx == 0:
            # reshuffle the class order
            classorder = numpy.random.permutation(ydim)
            #print 'class order', classorder
        
        classorderidx = classorder[classidx]
        #print 'classorderidx',classorderidx
        
        # check the SP[classidx] not empty
        if not SP[classorderidx]:
            #print 'SP[classidx] empty'
            continue
        
        ranidx = numpy.random.randint(len(SP[classorderidx]))
        #print 'randix',ranidx
        (idx0,idx1) = SP[classorderidx][ranidx]
        #print 'idx0,idx1',idx0,idx1
    
        n_samples = 0

        # Get random sample a piece of length batch_size from a song
        # idx0 = numpy.random.randint(0,len(train[0]))
        
        # batch_size_ = batch_size
        # while len(train[0][idx0]) <= batch_size_:
            # batch_size_ = batch_size_ / 2
            
        # idx1 = numpy.random.randint(0,len(train[0][idx0])-batch_size_) # 500 in our case
        
        iter += 1
        use_noise.set_value(1.)
        
        # Select the random examples for this minibatch
        endbound = min(idx1+batch_size,len(train[1][idx0]))
        x = train[0][idx0][idx1:idx1+batch_size]
        y = train[1][idx0][idx1:idx1+batch_size]
        
        # Get the data in numpy.ndarray format
        # This swap the axis!
        # Return something of shape (minibatch maxlen, n samples)
        n_samples += 1

        cost = f_grad_shared(x, y)
        f_update(lrate)

        # if numpy.isnan(cost) or numpy.isinf(cost):
            # print 'NaN detected'
            # return 1., 1., 1.

        if numpy.mod(iter, validation_frequency) == 0:
            use_noise.set_value(0.)
            
            this_validation_loss = pred_error(f_pred, valid)
            training_history.append([iter,this_validation_loss])
            print('epoch %i, validation error %f %%' %
                  (epoch, this_validation_loss * 100.))
            print('iter = %d' % iter)
            print('patience = %d' % patience)
            
            if this_validation_loss < best_validation_loss:
                    #improve patience if loss improvement is good enough
                    if (
                        this_validation_loss < best_validation_loss *
                        improvement_threshold
                    ):
                        patience = max(patience, iter * patience_increase)
                    
                    params = unzip(tparams)
                    numpy.savez(dumppath, training_history=training_history,
                                best_validation_loss=best_validation_loss,**params)
                        
                    # save best validation score and iteration number
                    best_validation_loss = this_validation_loss
                    best_iter = iter
                    print('best_validation_loss %f' % best_validation_loss)

        if patience <= iter:
                done_looping = True
                if earlystop:
                    break


    end_time = time.time()
    # final save
    numpy.savez(dumppath, training_history=training_history, best_validation_loss=best_validation_loss, **params)

    print(
        (
            'Optimization complete with best validation score of %f %%, '
            'obtained at iteration %i, '
        ) % (best_validation_loss * 100., best_iter + 1)
    )
    print >> sys.stderr, ('The fine tuning code for file ' +
                          os.path.split(__file__)[1] +
                          ' ran for %.2fm' % ((end_time - start_time)
                                              / 60.))