def pretrain_osm(lam_kld=0.0):
# Initialize a source of randomness
rng = np.random.RandomState(1234)
# Load some data to train/validate/test with
dataset = 'data/mnist.pkl.gz'
datasets = load_udm(dataset, zero_mean=False)
Xtr = datasets[0][0]
Xtr = Xtr.get_value(borrow=False)
Xva = datasets[2][0]
Xva = Xva.get_value(borrow=False)
print("Xtr.shape: {0:s}, Xva.shape: {1:s}".format(str(Xtr.shape),str(Xva.shape)))
# get and set some basic dataset information
Xtr_mean = np.mean(Xtr, axis=0)
tr_samples = Xtr.shape[0]
va_samples = Xva.shape[0]
batch_size = 100
batch_reps = 5
# setup some symbolic variables and stuff
Xd = T.matrix('Xd_base')
Xc = T.matrix('Xc_base')
Xm = T.matrix('Xm_base')
data_dim = Xtr.shape[1]
prior_sigma = 1.0
##########################
# NETWORK CONFIGURATIONS #
##########################
gn_params = {}
shared_config = [PRIOR_DIM, 1000, 1000]
top_config = [shared_config[-1], data_dim]
gn_params['shared_config'] = shared_config
gn_params['mu_config'] = top_config
gn_params['sigma_config'] = top_config
gn_params['activation'] = relu_actfun
gn_params['init_scale'] = 1.4
gn_params['lam_l2a'] = 0.0
gn_params['vis_drop'] = 0.0
gn_params['hid_drop'] = 0.0
gn_params['bias_noise'] = 0.0
gn_params['input_noise'] = 0.0
# choose some parameters for the continuous inferencer
in_params = {}
shared_config = [data_dim, 1000, 1000]
top_config = [shared_config[-1], PRIOR_DIM]
in_params['shared_config'] = shared_config
in_params['mu_config'] = top_config
in_params['sigma_config'] = top_config
in_params['activation'] = relu_actfun
in_params['init_scale'] = 1.4
in_params['lam_l2a'] = 0.0
in_params['vis_drop'] = 0.0
in_params['hid_drop'] = 0.0
in_params['bias_noise'] = 0.0
in_params['input_noise'] = 0.0
# Initialize the base networks for this OneStageModel
IN = InfNet(rng=rng, Xd=Xd, prior_sigma=prior_sigma, \
params=in_params, shared_param_dicts=None)
GN = InfNet(rng=rng, Xd=Xd, prior_sigma=prior_sigma, \
params=gn_params, shared_param_dicts=None)
# Initialize biases in IN and GN
IN.init_biases(0.2)
GN.init_biases(0.2)
#########################
# INITIALIZE THE GIPAIR #
#########################
osm_params = {}
osm_params['x_type'] = 'bernoulli'
osm_params['xt_transform'] = 'sigmoid'
osm_params['logvar_bound'] = LOGVAR_BOUND
OSM = OneStageModel(rng=rng, Xd=Xd, Xc=Xc, Xm=Xm, \
p_x_given_z=GN, q_z_given_x=IN, \
x_dim=data_dim, z_dim=PRIOR_DIM, params=osm_params)
OSM.set_lam_l2w(1e-5)
safe_mean = (0.9 * Xtr_mean) + 0.05
safe_mean_logit = np.log(safe_mean / (1.0 - safe_mean))
OSM.set_output_bias(safe_mean_logit)
OSM.set_input_bias(-Xtr_mean)
######################
# BASIC VAE TRAINING #
######################
out_file = open(RESULT_PATH+"pt_osm_results.txt", 'wb')
# Set initial learning rate and basic SGD hyper parameters
obs_costs = np.zeros((batch_size,))
costs = [0. for i in range(10)]
learn_rate = 0.0005
for i in range(150000):
scale = min(1.0, float(i) / 10000.0)
if ((i > 1) and ((i % 20000) == 0)):
learn_rate = learn_rate * 0.9
# do a minibatch update of the model, and compute some costs
tr_idx = npr.randint(low=0,high=tr_samples,size=(batch_size,))
Xd_batch = Xtr.take(tr_idx, axis=0)
Xc_batch = 0.0 * Xd_batch
Xm_batch = 0.0 * Xd_batch
# do a minibatch update of the model, and compute some costs
OSM.set_sgd_params(lr_1=(scale*learn_rate), mom_1=0.5, mom_2=0.98)
OSM.set_lam_nll(1.0)
OSM.set_lam_kld(lam_kld_1=(1.0 + (scale*(lam_kld-1.0))), lam_kld_2=0.0)
result = OSM.train_joint(Xd_batch, Xc_batch, Xm_batch, batch_reps)
costs = [(costs[j] + result[j]) for j in range(len(result))]
if ((i % 1000) == 0):
# record and then reset the cost trackers
costs = [(v / 1000.0) for v in costs]
str_1 = "-- batch {0:d} --".format(i)
str_2 = " joint_cost: {0:.4f}".format(costs[0])
str_3 = " nll_cost : {0:.4f}".format(costs[1])
str_4 = " kld_cost : {0:.4f}".format(costs[2])
str_5 = " reg_cost : {0:.4f}".format(costs[3])
costs = [0.0 for v in costs]
# print out some diagnostic information
joint_str = "\n".join([str_1, str_2, str_3, str_4, str_5])
print(joint_str)
out_file.write(joint_str+"\n")
out_file.flush()
if ((i % 2000) == 0):
Xva = row_shuffle(Xva)
model_samps = OSM.sample_from_prior(500)
file_name = RESULT_PATH+"pt_osm_samples_b{0:d}_XG.png".format(i)
utils.visualize_samples(model_samps, file_name, num_rows=20)
# compute information about free-energy on validation set
file_name = RESULT_PATH+"pt_osm_free_energy_b{0:d}.png".format(i)
fe_terms = OSM.compute_fe_terms(Xva[0:2500], 20)
fe_mean = np.mean(fe_terms[0]) + np.mean(fe_terms[1])
fe_str = " nll_bound : {0:.4f}".format(fe_mean)
print(fe_str)
out_file.write(fe_str+"\n")
utils.plot_scatter(fe_terms[1], fe_terms[0], file_name, \
x_label='Posterior KLd', y_label='Negative Log-likelihood')
# compute information about posterior KLds on validation set
file_name = RESULT_PATH+"pt_osm_post_klds_b{0:d}.png".format(i)
post_klds = OSM.compute_post_klds(Xva[0:2500])
post_dim_klds = np.mean(post_klds, axis=0)
utils.plot_stem(np.arange(post_dim_klds.shape[0]), post_dim_klds, \
file_name)
if ((i % 5000) == 0):
IN.save_to_file(f_name=RESULT_PATH+"pt_osm_params_b{0:d}_IN.pkl".format(i))
GN.save_to_file(f_name=RESULT_PATH+"pt_osm_params_b{0:d}_GN.pkl".format(i))
IN.save_to_file(f_name=RESULT_PATH+"pt_osm_params_IN.pkl")
GN.save_to_file(f_name=RESULT_PATH+"pt_osm_params_GN.pkl")
return
def pretrain_osm(lam_kld=0.0):
# Initialize a source of randomness
rng = np.random.RandomState(1234)
# Load some data to train/validate/test with
data_file = 'data/tfd_data_48x48.pkl'
dataset = load_tfd(tfd_pkl_name=data_file, which_set='unlabeled', fold='all')
Xtr_unlabeled = dataset[0]
dataset = load_tfd(tfd_pkl_name=data_file, which_set='train', fold='all')
Xtr_train = dataset[0]
Xtr = np.vstack([Xtr_unlabeled, Xtr_train])
dataset = load_tfd(tfd_pkl_name=data_file, which_set='valid', fold='all')
Xva = dataset[0]
tr_samples = Xtr.shape[0]
va_samples = Xva.shape[0]
batch_size = 400
batch_reps = 6
carry_frac = 0.25
carry_size = int(batch_size * carry_frac)
reset_prob = 0.04
# setup some symbolic variables and stuff
Xd = T.matrix('Xd_base')
Xc = T.matrix('Xc_base')
Xm = T.matrix('Xm_base')
data_dim = Xtr.shape[1]
prior_sigma = 1.0
Xtr_mean = np.mean(Xtr, axis=0)
##########################
# NETWORK CONFIGURATIONS #
##########################
gn_params = {}
shared_config = [PRIOR_DIM, 1500, 1500]
top_config = [shared_config[-1], data_dim]
gn_params['shared_config'] = shared_config
gn_params['mu_config'] = top_config
gn_params['sigma_config'] = top_config
gn_params['activation'] = relu_actfun
gn_params['init_scale'] = 1.4
gn_params['lam_l2a'] = 0.0
gn_params['vis_drop'] = 0.0
gn_params['hid_drop'] = 0.0
gn_params['bias_noise'] = 0.0
gn_params['input_noise'] = 0.0
# choose some parameters for the continuous inferencer
in_params = {}
shared_config = [data_dim, 1500, 1500]
top_config = [shared_config[-1], PRIOR_DIM]
in_params['shared_config'] = shared_config
in_params['mu_config'] = top_config
in_params['sigma_config'] = top_config
in_params['activation'] = relu_actfun
in_params['init_scale'] = 1.4
in_params['lam_l2a'] = 0.0
in_params['vis_drop'] = 0.0
in_params['hid_drop'] = 0.0
in_params['bias_noise'] = 0.0
in_params['input_noise'] = 0.0
# Initialize the base networks for this OneStageModel
IN = InfNet(rng=rng, Xd=Xd, prior_sigma=prior_sigma, \
params=in_params, shared_param_dicts=None)
GN = InfNet(rng=rng, Xd=Xd, prior_sigma=prior_sigma, \
params=gn_params, shared_param_dicts=None)
# Initialize biases in IN and GN
IN.init_biases(0.2)
GN.init_biases(0.2)
######################################
# LOAD AND RESTART FROM SAVED PARAMS #
######################################
# gn_fname = RESULT_PATH+"pt_osm_params_b110000_GN.pkl"
# in_fname = RESULT_PATH+"pt_osm_params_b110000_IN.pkl"
# IN = load_infnet_from_file(f_name=in_fname, rng=rng, Xd=Xd, \
# new_params=None)
# GN = load_infnet_from_file(f_name=gn_fname, rng=rng, Xd=Xd, \
# new_params=None)
# in_params = IN.params
# gn_params = GN.params
#########################
# INITIALIZE THE GIPAIR #
#########################
osm_params = {}
osm_params['x_type'] = 'bernoulli'
osm_params['xt_transform'] = 'sigmoid'
osm_params['logvar_bound'] = LOGVAR_BOUND
OSM = OneStageModel(rng=rng, Xd=Xd, Xc=Xc, Xm=Xm, \
p_x_given_z=GN, q_z_given_x=IN, \
x_dim=data_dim, z_dim=PRIOR_DIM, params=osm_params)
OSM.set_lam_l2w(1e-5)
safe_mean = (0.9 * Xtr_mean) + 0.05
safe_mean_logit = np.log(safe_mean / (1.0 - safe_mean))
OSM.set_output_bias(safe_mean_logit)
OSM.set_input_bias(-Xtr_mean)
######################
# BASIC VAE TRAINING #
######################
out_file = open(RESULT_PATH+"pt_osm_results.txt", 'wb')
# Set initial learning rate and basic SGD hyper parameters
obs_costs = np.zeros((batch_size,))
costs = [0. for i in range(10)]
learn_rate = 0.002
for i in range(200000):
scale = min(1.0, float(i) / 5000.0)
if ((i > 1) and ((i % 20000) == 0)):
learn_rate = learn_rate * 0.8
if (i < 50000):
momentum = 0.5
elif (i < 10000):
momentum = 0.7
else:
momentum = 0.9
if ((i == 0) or (npr.rand() < reset_prob)):
# sample a fully random batch
batch_idx = npr.randint(low=0,high=tr_samples,size=(batch_size,))
else:
# sample a partially random batch, which retains some portion of
# the worst scoring examples from the previous batch
fresh_idx = npr.randint(low=0,high=tr_samples,size=(batch_size-carry_size,))
batch_idx = np.concatenate((fresh_idx.ravel(), carry_idx.ravel()))
# do a minibatch update of the model, and compute some costs
tr_idx = npr.randint(low=0,high=tr_samples,size=(batch_size,))
Xd_batch = Xtr.take(tr_idx, axis=0)
Xc_batch = 0.0 * Xd_batch
Xm_batch = 0.0 * Xd_batch
# do a minibatch update of the model, and compute some costs
OSM.set_sgd_params(lr_1=(scale*learn_rate), \
mom_1=(scale*momentum), mom_2=0.98)
OSM.set_lam_nll(1.0)
OSM.set_lam_kld(lam_kld_1=scale*lam_kld, lam_kld_2=0.0, lam_kld_c=50.0)
result = OSM.train_joint(Xd_batch, Xc_batch, Xm_batch, batch_reps)
batch_costs = result[4] + result[5]
obs_costs = collect_obs_costs(batch_costs, batch_reps)
carry_idx = batch_idx[np.argsort(-obs_costs)[0:carry_size]]
costs = [(costs[j] + result[j]) for j in range(len(result))]
if ((i % 1000) == 0):
# record and then reset the cost trackers
costs = [(v / 1000.0) for v in costs]
str_1 = "-- batch {0:d} --".format(i)
str_2 = " joint_cost: {0:.4f}".format(costs[0])
str_3 = " nll_cost : {0:.4f}".format(costs[1])
str_4 = " kld_cost : {0:.4f}".format(costs[2])
str_5 = " reg_cost : {0:.4f}".format(costs[3])
costs = [0.0 for v in costs]
# print out some diagnostic information
joint_str = "\n".join([str_1, str_2, str_3, str_4, str_5])
print(joint_str)
out_file.write(joint_str+"\n")
out_file.flush()
if ((i % 2000) == 0):
Xva = row_shuffle(Xva)
model_samps = OSM.sample_from_prior(500)
file_name = RESULT_PATH+"pt_osm_samples_b{0:d}_XG.png".format(i)
utils.visualize_samples(model_samps, file_name, num_rows=20)
file_name = RESULT_PATH+"pt_osm_inf_weights_b{0:d}.png".format(i)
utils.visualize_samples(OSM.inf_weights.get_value(borrow=False).T, \
file_name, num_rows=30)
file_name = RESULT_PATH+"pt_osm_gen_weights_b{0:d}.png".format(i)
utils.visualize_samples(OSM.gen_weights.get_value(borrow=False), \
file_name, num_rows=30)
# compute information about free-energy on validation set
file_name = RESULT_PATH+"pt_osm_free_energy_b{0:d}.png".format(i)
fe_terms = OSM.compute_fe_terms(Xva[0:2500], 20)
fe_mean = np.mean(fe_terms[0]) + np.mean(fe_terms[1])
fe_str = " nll_bound : {0:.4f}".format(fe_mean)
print(fe_str)
out_file.write(fe_str+"\n")
utils.plot_scatter(fe_terms[1], fe_terms[0], file_name, \
x_label='Posterior KLd', y_label='Negative Log-likelihood')
# compute information about posterior KLds on validation set
file_name = RESULT_PATH+"pt_osm_post_klds_b{0:d}.png".format(i)
post_klds = OSM.compute_post_klds(Xva[0:2500])
post_dim_klds = np.mean(post_klds, axis=0)
utils.plot_stem(np.arange(post_dim_klds.shape[0]), post_dim_klds, \
file_name)
if ((i % 5000) == 0):
IN.save_to_file(f_name=RESULT_PATH+"pt_osm_params_b{0:d}_IN.pkl".format(i))
GN.save_to_file(f_name=RESULT_PATH+"pt_osm_params_b{0:d}_GN.pkl".format(i))
IN.save_to_file(f_name=RESULT_PATH+"pt_osm_params_IN.pkl")
GN.save_to_file(f_name=RESULT_PATH+"pt_osm_params_GN.pkl")
return
def pretrain_osm(lam_kld=0.0):
# Initialize a source of randomness
rng = np.random.RandomState(1234)
# Load some data to train/validate/test with
data_file = 'data/tfd_data_48x48.pkl'
dataset = load_tfd(tfd_pkl_name=data_file,
which_set='unlabeled',
fold='all')
Xtr_unlabeled = dataset[0]
dataset = load_tfd(tfd_pkl_name=data_file, which_set='train', fold='all')
Xtr_train = dataset[0]
Xtr = np.vstack([Xtr_unlabeled, Xtr_train])
dataset = load_tfd(tfd_pkl_name=data_file, which_set='valid', fold='all')
Xva = dataset[0]
tr_samples = Xtr.shape[0]
va_samples = Xva.shape[0]
batch_size = 400
batch_reps = 6
carry_frac = 0.25
carry_size = int(batch_size * carry_frac)
reset_prob = 0.04
# setup some symbolic variables and stuff
Xd = T.matrix('Xd_base')
Xc = T.matrix('Xc_base')
Xm = T.matrix('Xm_base')
data_dim = Xtr.shape[1]
prior_sigma = 1.0
Xtr_mean = np.mean(Xtr, axis=0)
##########################
# NETWORK CONFIGURATIONS #
##########################
gn_params = {}
shared_config = [PRIOR_DIM, 1500, 1500]
top_config = [shared_config[-1], data_dim]
gn_params['shared_config'] = shared_config
gn_params['mu_config'] = top_config
gn_params['sigma_config'] = top_config
gn_params['activation'] = relu_actfun
gn_params['init_scale'] = 1.4
gn_params['lam_l2a'] = 0.0
gn_params['vis_drop'] = 0.0
gn_params['hid_drop'] = 0.0
gn_params['bias_noise'] = 0.0
gn_params['input_noise'] = 0.0
# choose some parameters for the continuous inferencer
in_params = {}
shared_config = [data_dim, 1500, 1500]
top_config = [shared_config[-1], PRIOR_DIM]
in_params['shared_config'] = shared_config
in_params['mu_config'] = top_config
in_params['sigma_config'] = top_config
in_params['activation'] = relu_actfun
in_params['init_scale'] = 1.4
in_params['lam_l2a'] = 0.0
in_params['vis_drop'] = 0.0
in_params['hid_drop'] = 0.0
in_params['bias_noise'] = 0.0
in_params['input_noise'] = 0.0
# Initialize the base networks for this OneStageModel
IN = InfNet(rng=rng, Xd=Xd, prior_sigma=prior_sigma, \
params=in_params, shared_param_dicts=None)
GN = InfNet(rng=rng, Xd=Xd, prior_sigma=prior_sigma, \
params=gn_params, shared_param_dicts=None)
# Initialize biases in IN and GN
IN.init_biases(0.2)
GN.init_biases(0.2)
######################################
# LOAD AND RESTART FROM SAVED PARAMS #
######################################
# gn_fname = RESULT_PATH+"pt_osm_params_b110000_GN.pkl"
# in_fname = RESULT_PATH+"pt_osm_params_b110000_IN.pkl"
# IN = load_infnet_from_file(f_name=in_fname, rng=rng, Xd=Xd, \
# new_params=None)
# GN = load_infnet_from_file(f_name=gn_fname, rng=rng, Xd=Xd, \
# new_params=None)
# in_params = IN.params
# gn_params = GN.params
#########################
# INITIALIZE THE GIPAIR #
#########################
osm_params = {}
osm_params['x_type'] = 'bernoulli'
osm_params['xt_transform'] = 'sigmoid'
osm_params['logvar_bound'] = LOGVAR_BOUND
OSM = OneStageModel(rng=rng, Xd=Xd, Xc=Xc, Xm=Xm, \
p_x_given_z=GN, q_z_given_x=IN, \
x_dim=data_dim, z_dim=PRIOR_DIM, params=osm_params)
OSM.set_lam_l2w(1e-5)
safe_mean = (0.9 * Xtr_mean) + 0.05
safe_mean_logit = np.log(safe_mean / (1.0 - safe_mean))
OSM.set_output_bias(safe_mean_logit)
OSM.set_input_bias(-Xtr_mean)
######################
# BASIC VAE TRAINING #
######################
out_file = open(RESULT_PATH + "pt_osm_results.txt", 'wb')
# Set initial learning rate and basic SGD hyper parameters
obs_costs = np.zeros((batch_size, ))
costs = [0. for i in range(10)]
learn_rate = 0.002
for i in range(200000):
scale = min(1.0, float(i) / 5000.0)
if ((i > 1) and ((i % 20000) == 0)):
learn_rate = learn_rate * 0.8
if (i < 50000):
momentum = 0.5
elif (i < 10000):
momentum = 0.7
else:
momentum = 0.9
if ((i == 0) or (npr.rand() < reset_prob)):
# sample a fully random batch
batch_idx = npr.randint(low=0,
high=tr_samples,
size=(batch_size, ))
else:
# sample a partially random batch, which retains some portion of
# the worst scoring examples from the previous batch
fresh_idx = npr.randint(low=0,
high=tr_samples,
size=(batch_size - carry_size, ))
batch_idx = np.concatenate((fresh_idx.ravel(), carry_idx.ravel()))
# do a minibatch update of the model, and compute some costs
tr_idx = npr.randint(low=0, high=tr_samples, size=(batch_size, ))
Xd_batch = Xtr.take(tr_idx, axis=0)
Xc_batch = 0.0 * Xd_batch
Xm_batch = 0.0 * Xd_batch
# do a minibatch update of the model, and compute some costs
OSM.set_sgd_params(lr_1=(scale*learn_rate), \
mom_1=(scale*momentum), mom_2=0.98)
OSM.set_lam_nll(1.0)
OSM.set_lam_kld(lam_kld_1=scale * lam_kld,
lam_kld_2=0.0,
lam_kld_c=50.0)
result = OSM.train_joint(Xd_batch, Xc_batch, Xm_batch, batch_reps)
batch_costs = result[4] + result[5]
obs_costs = collect_obs_costs(batch_costs, batch_reps)
carry_idx = batch_idx[np.argsort(-obs_costs)[0:carry_size]]
costs = [(costs[j] + result[j]) for j in range(len(result))]
if ((i % 1000) == 0):
# record and then reset the cost trackers
costs = [(v / 1000.0) for v in costs]
str_1 = "-- batch {0:d} --".format(i)
str_2 = " joint_cost: {0:.4f}".format(costs[0])
str_3 = " nll_cost : {0:.4f}".format(costs[1])
str_4 = " kld_cost : {0:.4f}".format(costs[2])
str_5 = " reg_cost : {0:.4f}".format(costs[3])
costs = [0.0 for v in costs]
# print out some diagnostic information
joint_str = "\n".join([str_1, str_2, str_3, str_4, str_5])
print(joint_str)
out_file.write(joint_str + "\n")
out_file.flush()
if ((i % 2000) == 0):
Xva = row_shuffle(Xva)
model_samps = OSM.sample_from_prior(500)
file_name = RESULT_PATH + "pt_osm_samples_b{0:d}_XG.png".format(i)
utils.visualize_samples(model_samps, file_name, num_rows=20)
file_name = RESULT_PATH + "pt_osm_inf_weights_b{0:d}.png".format(i)
utils.visualize_samples(OSM.inf_weights.get_value(borrow=False).T, \
file_name, num_rows=30)
file_name = RESULT_PATH + "pt_osm_gen_weights_b{0:d}.png".format(i)
utils.visualize_samples(OSM.gen_weights.get_value(borrow=False), \
file_name, num_rows=30)
# compute information about free-energy on validation set
file_name = RESULT_PATH + "pt_osm_free_energy_b{0:d}.png".format(i)
fe_terms = OSM.compute_fe_terms(Xva[0:2500], 20)
fe_mean = np.mean(fe_terms[0]) + np.mean(fe_terms[1])
fe_str = " nll_bound : {0:.4f}".format(fe_mean)
print(fe_str)
out_file.write(fe_str + "\n")
utils.plot_scatter(fe_terms[1], fe_terms[0], file_name, \
x_label='Posterior KLd', y_label='Negative Log-likelihood')
# compute information about posterior KLds on validation set
file_name = RESULT_PATH + "pt_osm_post_klds_b{0:d}.png".format(i)
post_klds = OSM.compute_post_klds(Xva[0:2500])
post_dim_klds = np.mean(post_klds, axis=0)
utils.plot_stem(np.arange(post_dim_klds.shape[0]), post_dim_klds, \
file_name)
if ((i % 5000) == 0):
IN.save_to_file(f_name=RESULT_PATH +
"pt_osm_params_b{0:d}_IN.pkl".format(i))
GN.save_to_file(f_name=RESULT_PATH +
"pt_osm_params_b{0:d}_GN.pkl".format(i))
IN.save_to_file(f_name=RESULT_PATH + "pt_osm_params_IN.pkl")
GN.save_to_file(f_name=RESULT_PATH + "pt_osm_params_GN.pkl")
return
def pretrain_osm(lam_kld=0.0):
# Initialize a source of randomness
rng = np.random.RandomState(1234)
# Load some data to train/validate/test with
dataset = 'data/mnist.pkl.gz'
datasets = load_udm(dataset, zero_mean=False)
Xtr = datasets[0][0]
Xtr = Xtr.get_value(borrow=False)
Xva = datasets[2][0]
Xva = Xva.get_value(borrow=False)
print("Xtr.shape: {0:s}, Xva.shape: {1:s}".format(str(Xtr.shape),
str(Xva.shape)))
# get and set some basic dataset information
Xtr_mean = np.mean(Xtr, axis=0)
tr_samples = Xtr.shape[0]
va_samples = Xva.shape[0]
batch_size = 100
batch_reps = 5
# setup some symbolic variables and stuff
Xd = T.matrix('Xd_base')
Xc = T.matrix('Xc_base')
Xm = T.matrix('Xm_base')
data_dim = Xtr.shape[1]
prior_sigma = 1.0
##########################
# NETWORK CONFIGURATIONS #
##########################
gn_params = {}
shared_config = [PRIOR_DIM, 1000, 1000]
top_config = [shared_config[-1], data_dim]
gn_params['shared_config'] = shared_config
gn_params['mu_config'] = top_config
gn_params['sigma_config'] = top_config
gn_params['activation'] = relu_actfun
gn_params['init_scale'] = 1.4
gn_params['lam_l2a'] = 0.0
gn_params['vis_drop'] = 0.0
gn_params['hid_drop'] = 0.0
gn_params['bias_noise'] = 0.0
gn_params['input_noise'] = 0.0
# choose some parameters for the continuous inferencer
in_params = {}
shared_config = [data_dim, 1000, 1000]
top_config = [shared_config[-1], PRIOR_DIM]
in_params['shared_config'] = shared_config
in_params['mu_config'] = top_config
in_params['sigma_config'] = top_config
in_params['activation'] = relu_actfun
in_params['init_scale'] = 1.4
in_params['lam_l2a'] = 0.0
in_params['vis_drop'] = 0.0
in_params['hid_drop'] = 0.0
in_params['bias_noise'] = 0.0
in_params['input_noise'] = 0.0
# Initialize the base networks for this OneStageModel
IN = InfNet(rng=rng, Xd=Xd, prior_sigma=prior_sigma, \
params=in_params, shared_param_dicts=None)
GN = InfNet(rng=rng, Xd=Xd, prior_sigma=prior_sigma, \
params=gn_params, shared_param_dicts=None)
# Initialize biases in IN and GN
IN.init_biases(0.2)
GN.init_biases(0.2)
#########################
# INITIALIZE THE GIPAIR #
#########################
osm_params = {}
osm_params['x_type'] = 'bernoulli'
osm_params['xt_transform'] = 'sigmoid'
osm_params['logvar_bound'] = LOGVAR_BOUND
OSM = OneStageModel(rng=rng, Xd=Xd, Xc=Xc, Xm=Xm, \
p_x_given_z=GN, q_z_given_x=IN, \
x_dim=data_dim, z_dim=PRIOR_DIM, params=osm_params)
OSM.set_lam_l2w(1e-5)
safe_mean = (0.9 * Xtr_mean) + 0.05
safe_mean_logit = np.log(safe_mean / (1.0 - safe_mean))
OSM.set_output_bias(safe_mean_logit)
OSM.set_input_bias(-Xtr_mean)
######################
# BASIC VAE TRAINING #
######################
out_file = open(RESULT_PATH + "pt_osm_results.txt", 'wb')
# Set initial learning rate and basic SGD hyper parameters
obs_costs = np.zeros((batch_size, ))
costs = [0. for i in range(10)]
learn_rate = 0.0005
for i in range(150000):
scale = min(1.0, float(i) / 10000.0)
if ((i > 1) and ((i % 20000) == 0)):
learn_rate = learn_rate * 0.9
# do a minibatch update of the model, and compute some costs
tr_idx = npr.randint(low=0, high=tr_samples, size=(batch_size, ))
Xd_batch = Xtr.take(tr_idx, axis=0)
Xc_batch = 0.0 * Xd_batch
Xm_batch = 0.0 * Xd_batch
# do a minibatch update of the model, and compute some costs
OSM.set_sgd_params(lr_1=(scale * learn_rate), mom_1=0.5, mom_2=0.98)
OSM.set_lam_nll(1.0)
OSM.set_lam_kld(lam_kld_1=(1.0 + (scale * (lam_kld - 1.0))),
lam_kld_2=0.0)
result = OSM.train_joint(Xd_batch, Xc_batch, Xm_batch, batch_reps)
costs = [(costs[j] + result[j]) for j in range(len(result))]
if ((i % 1000) == 0):
# record and then reset the cost trackers
costs = [(v / 1000.0) for v in costs]
str_1 = "-- batch {0:d} --".format(i)
str_2 = " joint_cost: {0:.4f}".format(costs[0])
str_3 = " nll_cost : {0:.4f}".format(costs[1])
str_4 = " kld_cost : {0:.4f}".format(costs[2])
str_5 = " reg_cost : {0:.4f}".format(costs[3])
costs = [0.0 for v in costs]
# print out some diagnostic information
joint_str = "\n".join([str_1, str_2, str_3, str_4, str_5])
print(joint_str)
out_file.write(joint_str + "\n")
out_file.flush()
if ((i % 2000) == 0):
Xva = row_shuffle(Xva)
model_samps = OSM.sample_from_prior(500)
file_name = RESULT_PATH + "pt_osm_samples_b{0:d}_XG.png".format(i)
utils.visualize_samples(model_samps, file_name, num_rows=20)
# compute information about free-energy on validation set
file_name = RESULT_PATH + "pt_osm_free_energy_b{0:d}.png".format(i)
fe_terms = OSM.compute_fe_terms(Xva[0:2500], 20)
fe_mean = np.mean(fe_terms[0]) + np.mean(fe_terms[1])
fe_str = " nll_bound : {0:.4f}".format(fe_mean)
print(fe_str)
out_file.write(fe_str + "\n")
utils.plot_scatter(fe_terms[1], fe_terms[0], file_name, \
x_label='Posterior KLd', y_label='Negative Log-likelihood')
# compute information about posterior KLds on validation set
file_name = RESULT_PATH + "pt_osm_post_klds_b{0:d}.png".format(i)
post_klds = OSM.compute_post_klds(Xva[0:2500])
post_dim_klds = np.mean(post_klds, axis=0)
utils.plot_stem(np.arange(post_dim_klds.shape[0]), post_dim_klds, \
file_name)
if ((i % 5000) == 0):
IN.save_to_file(f_name=RESULT_PATH +
"pt_osm_params_b{0:d}_IN.pkl".format(i))
GN.save_to_file(f_name=RESULT_PATH +
"pt_osm_params_b{0:d}_GN.pkl".format(i))
IN.save_to_file(f_name=RESULT_PATH + "pt_osm_params_IN.pkl")
GN.save_to_file(f_name=RESULT_PATH + "pt_osm_params_GN.pkl")
return
def test_one_stage_model():
##########################
# Get some training data #
##########################
rng = np.random.RandomState(1234)
Xtr, Xva, Xte = load_binarized_mnist(data_path='./data/')
Xtr = np.vstack((Xtr, Xva))
Xva = Xte
#del Xte
tr_samples = Xtr.shape[0]
va_samples = Xva.shape[0]
batch_size = 128
batch_reps = 1
###############################################
# Setup some parameters for the OneStageModel #
###############################################
x_dim = Xtr.shape[1]
z_dim = 64
x_type = 'bernoulli'
xin_sym = T.matrix('xin_sym')
###############
# p_x_given_z #
###############
params = {}
shared_config = \
[ {'layer_type': 'fc',
'in_chans': z_dim,
'out_chans': 256,
'activation': relu_actfun,
'apply_bn': True}, \
{'layer_type': 'fc',
'in_chans': 256,
'out_chans': 7*7*128,
'activation': relu_actfun,
'apply_bn': True,
'shape_func_out': lambda x: T.reshape(x, (-1, 128, 7, 7))}, \
{'layer_type': 'conv',
'in_chans': 128, # in shape: (batch, 128, 7, 7)
'out_chans': 64, # out shape: (batch, 64, 14, 14)
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'half',
'apply_bn': True} ]
output_config = \
[ {'layer_type': 'conv',
'in_chans': 64, # in shape: (batch, 64, 14, 14)
'out_chans': 1, # out shape: (batch, 1, 28, 28)
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'half',
'apply_bn': False,
'shape_func_out': lambda x: T.flatten(x, 2)}, \
{'layer_type': 'conv',
'in_chans': 64,
'out_chans': 1,
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'half',
'apply_bn': False,
'shape_func_out': lambda x: T.flatten(x, 2)} ]
params['shared_config'] = shared_config
params['output_config'] = output_config
params['init_scale'] = 1.0
params['build_theano_funcs'] = False
p_x_given_z = HydraNet(rng=rng, Xd=xin_sym, \
params=params, shared_param_dicts=None)
p_x_given_z.init_biases(0.0)
###############
# q_z_given_x #
###############
params = {}
shared_config = \
[ {'layer_type': 'conv',
'in_chans': 1, # in shape: (batch, 784)
'out_chans': 64, # out shape: (batch, 64, 14, 14)
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'double',
'apply_bn': True,
'shape_func_in': lambda x: T.reshape(x, (-1, 1, 28, 28))}, \
{'layer_type': 'conv',
'in_chans': 64, # in shape: (batch, 64, 14, 14)
'out_chans': 128, # out shape: (batch, 128, 7, 7)
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'double',
'apply_bn': True,
'shape_func_out': lambda x: T.flatten(x, 2)}, \
{'layer_type': 'fc',
'in_chans': 128*7*7,
'out_chans': 256,
'activation': relu_actfun,
'apply_bn': True} ]
output_config = \
[ {'layer_type': 'fc',
'in_chans': 256,
'out_chans': z_dim,
'activation': relu_actfun,
'apply_bn': False}, \
{'layer_type': 'fc',
'in_chans': 256,
'out_chans': z_dim,
'activation': relu_actfun,
'apply_bn': False} ]
params['shared_config'] = shared_config
params['output_config'] = output_config
params['init_scale'] = 1.0
params['build_theano_funcs'] = False
q_z_given_x = HydraNet(rng=rng, Xd=xin_sym, \
params=params, shared_param_dicts=None)
q_z_given_x.init_biases(0.0)
##############################################################
# Define parameters for the TwoStageModel, and initialize it #
##############################################################
print("Building the OneStageModel...")
osm_params = {}
osm_params['x_type'] = x_type
osm_params['obs_transform'] = 'sigmoid'
OSM = OneStageModel(rng=rng, x_in=xin_sym,
x_dim=x_dim, z_dim=z_dim,
p_x_given_z=p_x_given_z,
q_z_given_x=q_z_given_x,
params=osm_params)
################################################################
# Apply some updates, to check that they aren't totally broken #
################################################################
log_name = "{}_RESULTS.txt".format("OSM_TEST")
out_file = open(log_name, 'wb')
costs = [0. for i in range(10)]
learn_rate = 0.0005
momentum = 0.9
batch_idx = np.arange(batch_size) + tr_samples
for i in range(500000):
scale = min(0.5, ((i+1) / 5000.0))
if (((i + 1) % 10000) == 0):
learn_rate = learn_rate * 0.95
# get the indices of training samples for this batch update
batch_idx += batch_size
if (np.max(batch_idx) >= tr_samples):
# we finished an "epoch", so we rejumble the training set
Xtr = row_shuffle(Xtr)
batch_idx = np.arange(batch_size)
Xb = to_fX( Xtr.take(batch_idx, axis=0) )
#Xb = binarize_data(Xtr.take(batch_idx, axis=0))
# set sgd and objective function hyperparams for this update
OSM.set_sgd_params(lr=scale*learn_rate, \
mom_1=(scale*momentum), mom_2=0.98)
OSM.set_lam_nll(lam_nll=1.0)
OSM.set_lam_kld(lam_kld=1.0)
OSM.set_lam_l2w(1e-5)
# perform a minibatch update and record the cost for this batch
result = OSM.train_joint(Xb, batch_reps)
costs = [(costs[j] + result[j]) for j in range(len(result))]
if ((i % 500) == 0):
costs = [(v / 500.0) for v in costs]
str1 = "-- batch {0:d} --".format(i)
str2 = " joint_cost: {0:.4f}".format(costs[0])
str3 = " nll_cost : {0:.4f}".format(costs[1])
str4 = " kld_cost : {0:.4f}".format(costs[2])
str5 = " reg_cost : {0:.4f}".format(costs[3])
joint_str = "\n".join([str1, str2, str3, str4, str5])
print(joint_str)
out_file.write(joint_str+"\n")
out_file.flush()
costs = [0.0 for v in costs]
if (((i % 5000) == 0) or ((i < 10000) and ((i % 1000) == 0))):
# draw some independent random samples from the model
samp_count = 300
model_samps = OSM.sample_from_prior(samp_count)
file_name = "OSM_SAMPLES_b{0:d}.png".format(i)
utils.visualize_samples(model_samps, file_name, num_rows=15)
# compute free energy estimate for validation samples
Xva = row_shuffle(Xva)
fe_terms = OSM.compute_fe_terms(Xva[0:5000], 20)
fe_mean = np.mean(fe_terms[0]) + np.mean(fe_terms[1])
out_str = " nll_bound : {0:.4f}".format(fe_mean)
print(out_str)
out_file.write(out_str+"\n")
out_file.flush()
return
def test_svhn(occ_dim=15, drop_prob=0.0):
RESULT_PATH = "IMP_SVHN_VAE/"
#########################################
# Format the result tag more thoroughly #
#########################################
dp_int = int(100.0 * drop_prob)
result_tag = "{}VAE_OD{}_DP{}".format(RESULT_PATH, occ_dim, dp_int)
##########################
# Get some training data #
##########################
tr_file = 'data/svhn_train_gray.pkl'
te_file = 'data/svhn_test_gray.pkl'
ex_file = 'data/svhn_extra_gray.pkl'
data = load_svhn_gray(tr_file, te_file, ex_file=ex_file, ex_count=200000)
Xtr = to_fX( shift_and_scale_into_01(np.vstack([data['Xtr'], data['Xex']])) )
Xva = to_fX( shift_and_scale_into_01(data['Xte']) )
tr_samples = Xtr.shape[0]
va_samples = Xva.shape[0]
batch_size = 250
all_pix_mean = np.mean(np.mean(Xtr, axis=1))
data_mean = to_fX( all_pix_mean * np.ones((Xtr.shape[1],)) )
############################################################
# Setup some parameters for the Iterative Refinement Model #
############################################################
obs_dim = Xtr.shape[1]
z_dim = 100
imp_steps = 15 # we'll check for the best step count (found oracularly)
init_scale = 1.0
x_in_sym = T.matrix('x_in_sym')
x_out_sym = T.matrix('x_out_sym')
x_mask_sym = T.matrix('x_mask_sym')
#################
# p_zi_given_xi #
#################
params = {}
shared_config = [obs_dim, 1000, 1000]
top_config = [shared_config[-1], z_dim]
params['shared_config'] = shared_config
params['mu_config'] = top_config
params['sigma_config'] = top_config
params['activation'] = relu_actfun
params['init_scale'] = init_scale
params['lam_l2a'] = 0.0
params['vis_drop'] = 0.0
params['hid_drop'] = 0.0
params['bias_noise'] = 0.0
params['input_noise'] = 0.0
params['build_theano_funcs'] = False
p_zi_given_xi = InfNet(rng=rng, Xd=x_in_sym, \
params=params, shared_param_dicts=None)
p_zi_given_xi.init_biases(0.2)
###################
# p_xip1_given_zi #
###################
params = {}
shared_config = [z_dim, 1000, 1000]
output_config = [obs_dim, obs_dim]
params['shared_config'] = shared_config
params['output_config'] = output_config
params['activation'] = relu_actfun
params['init_scale'] = init_scale
params['lam_l2a'] = 0.0
params['vis_drop'] = 0.0
params['hid_drop'] = 0.0
params['bias_noise'] = 0.0
params['input_noise'] = 0.0
params['build_theano_funcs'] = False
p_xip1_given_zi = HydraNet(rng=rng, Xd=x_in_sym, \
params=params, shared_param_dicts=None)
p_xip1_given_zi.init_biases(0.2)
###################
# q_zi_given_x_xi #
###################
params = {}
shared_config = [(obs_dim + obs_dim), 1000, 1000]
top_config = [shared_config[-1], z_dim]
params['shared_config'] = shared_config
params['mu_config'] = top_config
params['sigma_config'] = top_config
params['activation'] = relu_actfun
params['init_scale'] = init_scale
params['lam_l2a'] = 0.0
params['vis_drop'] = 0.0
params['hid_drop'] = 0.0
params['bias_noise'] = 0.0
params['input_noise'] = 0.0
params['build_theano_funcs'] = False
q_zi_given_x_xi = InfNet(rng=rng, Xd=x_in_sym, \
params=params, shared_param_dicts=None)
q_zi_given_x_xi.init_biases(0.2)
###########################################################
# Define parameters for the GPSImputer, and initialize it #
###########################################################
print("Building the GPSImputer...")
gpsi_params = {}
gpsi_params['obs_dim'] = obs_dim
gpsi_params['z_dim'] = z_dim
gpsi_params['imp_steps'] = imp_steps
gpsi_params['step_type'] = 'jump'
gpsi_params['x_type'] = 'bernoulli'
gpsi_params['obs_transform'] = 'sigmoid'
gpsi_params['use_osm_mode'] = True
GPSI = GPSImputer(rng=rng,
x_in=x_in_sym, x_out=x_out_sym, x_mask=x_mask_sym, \
p_zi_given_xi=p_zi_given_xi, \
p_xip1_given_zi=p_xip1_given_zi, \
q_zi_given_x_xi=q_zi_given_x_xi, \
params=gpsi_params, \
shared_param_dicts=None)
#########################################################################
# Define parameters for the underlying OneStageModel, and initialize it #
#########################################################################
print("Building the OneStageModel...")
osm_params = {}
osm_params['x_type'] = 'bernoulli'
osm_params['xt_transform'] = 'sigmoid'
OSM = OneStageModel(rng=rng, \
x_in=x_in_sym, \
p_x_given_z=p_xip1_given_zi, \
q_z_given_x=p_zi_given_xi, \
x_dim=obs_dim, z_dim=z_dim, \
params=osm_params)
################################################################
# Apply some updates, to check that they aren't totally broken #
################################################################
log_name = "{}_RESULTS.txt".format(result_tag)
out_file = open(log_name, 'wb')
costs = [0. for i in range(10)]
learn_rate = 0.0002
momentum = 0.5
batch_idx = np.arange(batch_size) + tr_samples
for i in range(200005):
scale = min(1.0, ((i+1) / 5000.0))
if (((i + 1) % 15000) == 0):
learn_rate = learn_rate * 0.92
if (i > 10000):
momentum = 0.90
else:
momentum = 0.50
# get the indices of training samples for this batch update
batch_idx += batch_size
if (np.max(batch_idx) >= tr_samples):
# we finished an "epoch", so we rejumble the training set
Xtr = row_shuffle(Xtr)
batch_idx = np.arange(batch_size)
# set sgd and objective function hyperparams for this update
OSM.set_sgd_params(lr=scale*learn_rate, \
mom_1=scale*momentum, mom_2=0.99)
OSM.set_lam_nll(lam_nll=1.0)
OSM.set_lam_kld(lam_kld_1=1.0, lam_kld_2=0.0)
OSM.set_lam_l2w(1e-4)
# perform a minibatch update and record the cost for this batch
xb = to_fX( Xtr.take(batch_idx, axis=0) )
result = OSM.train_joint(xb, batch_reps)
costs = [(costs[j] + result[j]) for j in range(len(result)-1)]
if ((i % 250) == 0):
costs = [(v / 250.0) for v in costs]
str1 = "-- batch {0:d} --".format(i)
str2 = " joint_cost: {0:.4f}".format(costs[0])
str3 = " nll_cost : {0:.4f}".format(costs[1])
str4 = " kld_cost : {0:.4f}".format(costs[2])
str5 = " reg_cost : {0:.4f}".format(costs[3])
joint_str = "\n".join([str1, str2, str3, str4, str5])
print(joint_str)
out_file.write(joint_str+"\n")
out_file.flush()
costs = [0.0 for v in costs]
if ((i % 1000) == 0):
Xva = row_shuffle(Xva)
# record an estimate of performance on the test set
xi, xo, xm = construct_masked_data(Xva[0:5000], drop_prob=drop_prob, \
occ_dim=occ_dim, data_mean=data_mean)
step_nll, step_kld = GPSI.compute_per_step_cost(xi, xo, xm, sample_count=10)
min_nll = np.min(step_nll)
str1 = " va_nll_bound : {}".format(min_nll)
str2 = " va_nll_min : {}".format(min_nll)
str3 = " va_nll_final : {}".format(step_nll[-1])
joint_str = "\n".join([str1, str2, str3])
print(joint_str)
out_file.write(joint_str+"\n")
out_file.flush()
if ((i % 10000) == 0):
# Get some validation samples for evaluating model performance
xb = to_fX( Xva[0:100] )
xi, xo, xm = construct_masked_data(xb, drop_prob=drop_prob, \
occ_dim=occ_dim, data_mean=data_mean)
xi = np.repeat(xi, 2, axis=0)
xo = np.repeat(xo, 2, axis=0)
xm = np.repeat(xm, 2, axis=0)
# draw some sample imputations from the model
samp_count = xi.shape[0]
_, model_samps = GPSI.sample_imputer(xi, xo, xm, use_guide_policy=False)
seq_len = len(model_samps)
seq_samps = np.zeros((seq_len*samp_count, model_samps[0].shape[1]))
idx = 0
for s1 in range(samp_count):
for s2 in range(seq_len):
seq_samps[idx] = model_samps[s2][s1]
idx += 1
file_name = "{}_samples_ng_b{}.png".format(result_tag, i)
utils.visualize_samples(seq_samps, file_name, num_rows=20)
# get visualizations of policy parameters
file_name = "{}_gen_gen_weights_b{}.png".format(result_tag, i)
W = GPSI.gen_gen_weights.get_value(borrow=False)
utils.visualize_samples(W[:,:obs_dim], file_name, num_rows=20)
file_name = "{}_gen_inf_weights_b{}.png".format(result_tag, i)
W = GPSI.gen_inf_weights.get_value(borrow=False).T
utils.visualize_samples(W[:,:obs_dim], file_name, num_rows=20)
def test_one_stage_model():
##########################
# Get some training data #
##########################
rng = np.random.RandomState(1234)
Xtr, Xva, Xte = load_binarized_mnist(data_path='./data/')
Xtr = np.vstack((Xtr, Xva))
Xva = Xte
#del Xte
tr_samples = Xtr.shape[0]
va_samples = Xva.shape[0]
batch_size = 128
batch_reps = 1
###############################################
# Setup some parameters for the OneStageModel #
###############################################
x_dim = Xtr.shape[1]
z_dim = 64
x_type = 'bernoulli'
xin_sym = T.matrix('xin_sym')
###############
# p_x_given_z #
###############
params = {}
shared_config = \
[ {'layer_type': 'fc',
'in_chans': z_dim,
'out_chans': 256,
'activation': relu_actfun,
'apply_bn': True}, \
{'layer_type': 'fc',
'in_chans': 256,
'out_chans': 7*7*128,
'activation': relu_actfun,
'apply_bn': True,
'shape_func_out': lambda x: T.reshape(x, (-1, 128, 7, 7))}, \
{'layer_type': 'conv',
'in_chans': 128, # in shape: (batch, 128, 7, 7)
'out_chans': 64, # out shape: (batch, 64, 14, 14)
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'half',
'apply_bn': True} ]
output_config = \
[ {'layer_type': 'conv',
'in_chans': 64, # in shape: (batch, 64, 14, 14)
'out_chans': 1, # out shape: (batch, 1, 28, 28)
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'half',
'apply_bn': False,
'shape_func_out': lambda x: T.flatten(x, 2)}, \
{'layer_type': 'conv',
'in_chans': 64,
'out_chans': 1,
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'half',
'apply_bn': False,
'shape_func_out': lambda x: T.flatten(x, 2)} ]
params['shared_config'] = shared_config
params['output_config'] = output_config
params['init_scale'] = 1.0
params['build_theano_funcs'] = False
p_x_given_z = HydraNet(rng=rng, Xd=xin_sym, \
params=params, shared_param_dicts=None)
p_x_given_z.init_biases(0.0)
###############
# q_z_given_x #
###############
params = {}
shared_config = \
[ {'layer_type': 'conv',
'in_chans': 1, # in shape: (batch, 784)
'out_chans': 64, # out shape: (batch, 64, 14, 14)
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'double',
'apply_bn': True,
'shape_func_in': lambda x: T.reshape(x, (-1, 1, 28, 28))}, \
{'layer_type': 'conv',
'in_chans': 64, # in shape: (batch, 64, 14, 14)
'out_chans': 128, # out shape: (batch, 128, 7, 7)
'activation': relu_actfun,
'filt_dim': 5,
'conv_stride': 'double',
'apply_bn': True,
'shape_func_out': lambda x: T.flatten(x, 2)}, \
{'layer_type': 'fc',
'in_chans': 128*7*7,
'out_chans': 256,
'activation': relu_actfun,
'apply_bn': True} ]
output_config = \
[ {'layer_type': 'fc',
'in_chans': 256,
'out_chans': z_dim,
'activation': relu_actfun,
'apply_bn': False}, \
{'layer_type': 'fc',
'in_chans': 256,
'out_chans': z_dim,
'activation': relu_actfun,
'apply_bn': False} ]
params['shared_config'] = shared_config
params['output_config'] = output_config
params['init_scale'] = 1.0
params['build_theano_funcs'] = False
q_z_given_x = HydraNet(rng=rng, Xd=xin_sym, \
params=params, shared_param_dicts=None)
q_z_given_x.init_biases(0.0)
##############################################################
# Define parameters for the TwoStageModel, and initialize it #
##############################################################
print("Building the OneStageModel...")
osm_params = {}
osm_params['x_type'] = x_type
osm_params['obs_transform'] = 'sigmoid'
OSM = OneStageModel(rng=rng,
x_in=xin_sym,
x_dim=x_dim,
z_dim=z_dim,
p_x_given_z=p_x_given_z,
q_z_given_x=q_z_given_x,
params=osm_params)
################################################################
# Apply some updates, to check that they aren't totally broken #
################################################################
log_name = "{}_RESULTS.txt".format("OSM_TEST")
out_file = open(log_name, 'wb')
costs = [0. for i in range(10)]
learn_rate = 0.0005
momentum = 0.9
batch_idx = np.arange(batch_size) + tr_samples
for i in range(500000):
scale = min(0.5, ((i + 1) / 5000.0))
if (((i + 1) % 10000) == 0):
learn_rate = learn_rate * 0.95
# get the indices of training samples for this batch update
batch_idx += batch_size
if (np.max(batch_idx) >= tr_samples):
# we finished an "epoch", so we rejumble the training set
Xtr = row_shuffle(Xtr)
batch_idx = np.arange(batch_size)
Xb = to_fX(Xtr.take(batch_idx, axis=0))
#Xb = binarize_data(Xtr.take(batch_idx, axis=0))
# set sgd and objective function hyperparams for this update
OSM.set_sgd_params(lr=scale*learn_rate, \
mom_1=(scale*momentum), mom_2=0.98)
OSM.set_lam_nll(lam_nll=1.0)
OSM.set_lam_kld(lam_kld=1.0)
OSM.set_lam_l2w(1e-5)
# perform a minibatch update and record the cost for this batch
result = OSM.train_joint(Xb, batch_reps)
costs = [(costs[j] + result[j]) for j in range(len(result))]
if ((i % 500) == 0):
costs = [(v / 500.0) for v in costs]
str1 = "-- batch {0:d} --".format(i)
str2 = " joint_cost: {0:.4f}".format(costs[0])
str3 = " nll_cost : {0:.4f}".format(costs[1])
str4 = " kld_cost : {0:.4f}".format(costs[2])
str5 = " reg_cost : {0:.4f}".format(costs[3])
joint_str = "\n".join([str1, str2, str3, str4, str5])
print(joint_str)
out_file.write(joint_str + "\n")
out_file.flush()
costs = [0.0 for v in costs]
if (((i % 5000) == 0) or ((i < 10000) and ((i % 1000) == 0))):
# draw some independent random samples from the model
samp_count = 300
model_samps = OSM.sample_from_prior(samp_count)
file_name = "OSM_SAMPLES_b{0:d}.png".format(i)
utils.visualize_samples(model_samps, file_name, num_rows=15)
# compute free energy estimate for validation samples
Xva = row_shuffle(Xva)
fe_terms = OSM.compute_fe_terms(Xva[0:5000], 20)
fe_mean = np.mean(fe_terms[0]) + np.mean(fe_terms[1])
out_str = " nll_bound : {0:.4f}".format(fe_mean)
print(out_str)
out_file.write(out_str + "\n")
out_file.flush()
return
