def load_train_data(dataset='mnist'):
if dataset == 'mnist':
train_data, _, _ = mnistio.load_data()
elif dataset == 'tfd':
train_data, _, _ = tfd.load_proper_fold(0, 'unlabeled', scale=True)
train_data = train_data.reshape(train_data.shape[0],
np.prod(train_data.shape[1:]))
return train_data
def mnist_mmd_input_space(n_hids=[10, 64, 256, 256, 1024],
sigma=[2, 5, 10, 20, 40, 80],
learn_rate=2,
momentum=0.9):
"""
n_hids: number of hidden units on all layers (top-down) in the generative network.
sigma: a list of scales used for the kernel
learn_rate, momentum: parameters for the learning process
return: KDE log_likelihood on validation set.
"""
gnp.seed_rand(8)
x_train, x_val, x_test = mnistio.load_data()
print ''
print 'Training data: %d x %d' % x_train.shape
in_dim = n_hids[0]
out_dim = x_train.shape[1]
net = gen.StochasticGenerativeNet(in_dim, out_dim)
for i in range(1, len(n_hids)):
net.add_layer(n_hids[i], nonlin_type=ly.NONLIN_NAME_RELU, dropout=0)
net.add_layer(0, nonlin_type=ly.NONLIN_NAME_SIGMOID, dropout=0)
# place holder loss
net.set_loss(ls.LOSS_NAME_MMDGEN,
loss_after_nonlin=True,
sigma=80,
loss_weight=1000)
print ''
print '========'
print 'Training'
print '========'
print ''
print net
print ''
mmd_learner = gen.StochasticGenerativeNetLearner(net)
mmd_learner.load_data(x_train)
output_base = OUTPUT_BASE_DIR + '/mnist/input_space'
#sigma = [2,5,10,20,40,80]
sigma_weights = [1, 1, 1, 1, 1, 1]
#learn_rate = 1
#momentum = 0.9
minibatch_size = 1000
n_sample_update_iters = 1
max_iters = 40000
i_checkpoint = 2000
output_dir = output_base + '/nhids_%s_sigma_%s_lr_%s_m_%s' % ('_'.join([
str(nh) for nh in n_hids
]), '_'.join([str(s) for s in sigma]), str(learn_rate), str(momentum))
print ''
print '>>>> output_dir = %s' % output_dir
print ''
mmd_learner.set_output_dir(output_dir)
#net.set_loss(ls.LOSS_NAME_MMDGEN_MULTISCALE, loss_after_nonlin=True, sigma=sigma, scale_weight=sigma_weights, loss_weight=1000)
net.set_loss(ls.LOSS_NAME_MMDGEN_SQRT_GAUSSIAN,
loss_after_nonlin=True,
sigma=sigma,
scale_weight=sigma_weights,
loss_weight=1000)
print '**********************************'
print net.loss
print '**********************************'
print ''
def f_checkpoint(i_iter, w):
mmd_learner.save_checkpoint('%d' % i_iter)
mmd_learner.train_sgd(minibatch_size=minibatch_size,
n_samples_per_update=minibatch_size,
n_sample_update_iters=n_sample_update_iters,
learn_rate=learn_rate,
momentum=momentum,
weight_decay=0,
learn_rate_schedule={10000: learn_rate / 10.0},
momentum_schedule={10000: 1 - (1 - momentum) / 10.0},
learn_rate_drop_iters=0,
decrease_type='linear',
adagrad_start_iter=0,
max_iters=max_iters,
iprint=100,
i_exe=i_checkpoint,
f_exe=f_checkpoint)
mmd_learner.save_model()
print ''
print '===================='
print 'Evaluating the model'
print '===================='
print ''
log_prob, std, sigma = ev.kde_eval_mnist(net, x_val, verbose=False)
test_log_prob, test_std, _ = ev.kde_eval_mnist(net,
x_test,
sigma_range=[sigma],
verbose=False)
print 'Validation: %.2f (%.2f)' % (log_prob, std)
print 'Test : %.2f (%.2f)' % (test_log_prob, test_std)
print ''
write_config(
output_dir + '/params_and_results.cfg', {
'n_hids': n_hids,
'sigma': sigma,
'sigma_weights': sigma_weights,
'learn_rate': learn_rate,
'momentum': momentum,
'minibatch_size': minibatch_size,
'n_sample_update_iters': n_sample_update_iters,
'max_iters': max_iters,
'i_checkpoint': i_checkpoint,
'val_log_prob': log_prob,
'val_std': std,
'test_log_prob': test_log_prob,
'test_std': test_std
})
print '>>>> output_dir = %s' % output_dir
print ''
return log_prob
def mnist_mmd_code_space(ae_n_hids=[1024, 32],
ae_dropout=[0.2, 0.5],
ae_learn_rate=1e-1,
ae_momentum=0.9,
mmd_n_hids=[10, 64, 256, 256, 1024],
mmd_sigma=1,
mmd_learn_rate=2,
mmd_momentum=0.9):
"""
ae_n_hids: #hid for the encoder, bottom-up
ae_dropout: the amount of dropout for each layer in the encoder, same order
ae_learn_rate, ae_momentum: .
mmd_n_hids: #hid for the generative net, top-down
mmd_sigma: scale of the kernel
mmd_learn_rate, mmd_momentum: .
Return KDE log_likelihood on the validation set.
"""
gnp.seed_rand(8)
x_train, x_val, x_test = mnistio.load_data()
common_output_base = OUTPUT_BASE_DIR + '/mnist/code_space'
output_base = common_output_base + '/aeh_%s_dr_%s_aelr_%s_aem_%s_nh_%s_s_%s_lr_%s_m_%s' % (
cat_list(ae_n_hids), cat_list(ae_dropout), str(ae_learn_rate),
str(ae_momentum), cat_list(mmd_n_hids), str(mmd_sigma),
str(mmd_learn_rate), str(mmd_momentum))
#######################
# Auto-encoder training
#######################
n_dims = x_train.shape[1]
h_dim = ae_n_hids[-1]
encoder = nn.NeuralNet(n_dims, h_dim)
for i in range(len(ae_n_hids) - 1):
encoder.add_layer(ae_n_hids[i],
nonlin_type=ly.NONLIN_NAME_SIGMOID,
dropout=ae_dropout[i])
encoder.add_layer(0,
nonlin_type=ly.NONLIN_NAME_SIGMOID,
dropout=ae_dropout[-1])
decoder = nn.NeuralNet(h_dim, n_dims)
for i in range(len(ae_n_hids) - 1)[::-1]:
decoder.add_layer(ae_n_hids[i],
nonlin_type=ly.NONLIN_NAME_SIGMOID,
dropout=0)
decoder.add_layer(0, nonlin_type=ly.NONLIN_NAME_SIGMOID, dropout=0)
decoder.set_loss(ls.LOSS_NAME_BINARY_CROSSENTROPY, loss_weight=1)
autoenc = nn.AutoEncoder(encoder=encoder, decoder=decoder)
print ''
print autoenc
print ''
learn_rate = ae_learn_rate
final_momentum = ae_momentum
max_iters = 3000
nn_pretrainer = learner.AutoEncoderPretrainer(autoenc)
nn_pretrainer.load_data(x_train)
nn_pretrainer.pretrain_network(learn_rate=1e-1,
momentum=0.5,
weight_decay=0,
minibatch_size=100,
max_grad_norm=10,
max_iters=max_iters,
iprint=100)
nn_learner = learner.Learner(autoenc)
nn_learner.set_output_dir(output_base + '/ae')
nn_learner.load_data(x_train, x_train)
def f_checkpoint(i_iter, w):
nn_learner.save_checkpoint('%d' % i_iter)
nn_learner.train_sgd(learn_rate=learn_rate,
momentum=0,
weight_decay=0,
minibatch_size=100,
learn_rate_schedule=None,
momentum_schedule={
50: 0.5,
200: final_momentum
},
max_grad_norm=10,
learn_rate_drop_iters=0,
decrease_type='linear',
adagrad_start_iter=0,
max_iters=max_iters,
iprint=100,
i_exe=2000,
f_exe=f_checkpoint)
nn_learner.save_checkpoint('best')
##################
# Training MMD net
##################
n_hids = mmd_n_hids
in_dim = n_hids[0]
out_dim = autoenc.encoder.out_dim
net = gen.StochasticGenerativeNetWithAutoencoder(in_dim, out_dim, autoenc)
for i in range(1, len(n_hids)):
net.add_layer(n_hids[i], nonlin_type=ly.NONLIN_NAME_RELU, dropout=0)
net.add_layer(0, nonlin_type=ly.NONLIN_NAME_SIGMOID, dropout=0)
print ''
print '========'
print 'Training'
print '========'
print ''
print net
print ''
mmd_learner = gen.StochasticGenerativeNetLearner(net)
mmd_learner.load_data(x_train)
sigma = [mmd_sigma]
sigma_weights = [1]
learn_rate = mmd_learn_rate
momentum = mmd_momentum
minibatch_size = 1000
n_sample_update_iters = 1
max_iters = 40000
i_checkpoint = 2000
mmd_learner.set_output_dir(output_base + '/mmd')
#net.set_loss(ls.LOSS_NAME_MMDGEN_MULTISCALE, loss_after_nonlin=True, sigma=sigma, scale_weight=sigma_weights, loss_weight=1000)
net.set_loss(ls.LOSS_NAME_MMDGEN_SQRT_GAUSSIAN,
loss_after_nonlin=True,
sigma=sigma,
scale_weight=sigma_weights,
loss_weight=1000)
print '**********************************'
print net.loss
print '**********************************'
print ''
def f_checkpoint(i_iter, w):
mmd_learner.save_checkpoint('%d' % i_iter)
mmd_learner.train_sgd(minibatch_size=minibatch_size,
n_samples_per_update=minibatch_size,
n_sample_update_iters=n_sample_update_iters,
learn_rate=learn_rate,
momentum=momentum,
weight_decay=0,
learn_rate_schedule={10000: learn_rate / 10.0},
momentum_schedule={10000: 1 - (1 - momentum) / 10.0},
learn_rate_drop_iters=0,
decrease_type='linear',
adagrad_start_iter=0,
max_iters=max_iters,
iprint=100,
i_exe=i_checkpoint,
f_exe=f_checkpoint)
mmd_learner.save_model()
# Evaluation
print ''
print '===================='
print 'Evaluating the model'
print '===================='
print ''
log_prob, std, sigma = ev.kde_eval_mnist(net, x_val, verbose=False)
test_log_prob, test_std, _ = ev.kde_eval_mnist(net,
x_test,
sigma_range=[sigma],
verbose=False)
print 'Validation: %.2f (%.2f)' % (log_prob, std)
print 'Test : %.2f (%.2f)' % (test_log_prob, test_std)
print ''
write_config(
output_base + '/params_and_results.cfg', {
'ae_n_hids': ae_n_hids,
'ae_dropout': ae_dropout,
'ae_learn_rate': ae_learn_rate,
'ae_momentum': ae_momentum,
'mmd_n_hids': mmd_n_hids,
'mmd_sigma': mmd_sigma,
'mmd_sigma_weights': sigma_weights,
'mmd_learn_rate': mmd_learn_rate,
'mmd_momentum': mmd_momentum,
'mmd_minibatch_size': minibatch_size,
'mmd_n_sample_update_iters': n_sample_update_iters,
'mmd_max_iters': max_iters,
'mmd_i_checkpoint': i_checkpoint,
'val_log_prob': log_prob,
'val_std': std,
'test_log_prob': test_log_prob,
'test_std': test_std
})
print '>>>> output_dir = %s' % output_base
print ''
return log_prob
