class EncoderDecoder(object):
def __init__(self, rng, **kwargs):
self.n_in_src = kwargs.pop('nembed_src')
self.n_in_trg = kwargs.pop('nembed_trg')
self.n_hids_src = kwargs.pop('nhids_src')
self.n_hids_trg = kwargs.pop('nhids_trg')
self.src_vocab_size = kwargs.pop('src_vocab_size')
self.trg_vocab_size = kwargs.pop('trg_vocab_size')
self.method = kwargs.pop('method')
self.dropout = kwargs.pop('dropout')
self.maxout_part = kwargs.pop('maxout_part')
self.path = kwargs.pop('saveto')
self.clip_c = kwargs.pop('clip_c')
self.rng = rng
self.trng = RandomStreams(rng.randint(1e5))
# added by Zhaopeng Tu, 2016-06-09
self.with_attention = kwargs.pop('with_attention')
# added by Zhaopeng Tu, 2016-04-29
self.with_coverage = kwargs.pop('with_coverage')
self.coverage_dim = kwargs.pop('coverage_dim')
self.coverage_type = kwargs.pop('coverage_type')
self.max_fertility = kwargs.pop('max_fertility')
if self.coverage_type is 'linguistic':
# make sure the dimension of linguistic coverage is always 1
self.coverage_dim = 1
# added by Zhaopeng Tu, 2016-05-30
self.with_context_gate = kwargs.pop('with_context_gate')
self.params = []
self.layers = []
self.table_src = LookupTable(self.rng,
self.src_vocab_size,
self.n_in_src,
name='table_src')
self.layers.append(self.table_src)
self.encoder = BidirectionalEncoder(self.rng,
self.n_in_src,
self.n_hids_src,
self.table_src,
name='birnn_encoder')
self.layers.append(self.encoder)
# added by Longyue
self.encoder_hist_1 = Encoder(self.rng,
self.n_in_src,
self.n_hids_src,
self.table_src,
name='rnn_encoder_hist_1')
self.layers.append(self.encoder_hist_1)
self.encoder_hist_2 = Encoder(self.rng,
self.n_hids_src,
self.n_hids_src,
self.table_src,
name='rnn_encoder_hist_2')
self.layers.append(self.encoder_hist_2)
self.table_trg = LookupTable(self.rng,
self.trg_vocab_size,
self.n_in_trg,
name='table_trg')
self.layers.append(self.table_trg)
self.decoder = Decoder(self.rng, self.n_in_trg, self.n_hids_trg, 2*self.n_hids_src, self.n_hids_src, \
# added by Zhaopeng Tu, 2016-06-09
with_attention=self.with_attention, \
# added by Zhaopeng Tu, 2016-04-29
with_coverage=self.with_coverage, coverage_dim=self.coverage_dim, coverage_type=self.coverage_type, max_fertility=self.max_fertility, \
# added by Zhaopeng Tu, 2016-05-30
with_context_gate=self.with_context_gate, \
maxout_part=self.maxout_part, name='rnn_decoder')
self.layers.append(self.decoder)
self.logistic_layer = LogisticRegression(self.rng, self.n_in_trg,
self.trg_vocab_size)
self.layers.append(self.logistic_layer)
# added by Zhaopeng Tu, 2016-07-12
# for reconstruction
self.with_reconstruction = kwargs.pop('with_reconstruction')
if self.with_reconstruction:
# added by Zhaopeng Tu, 2016-07-27
self.reconstruction_weight = kwargs.pop('reconstruction_weight')
# note the source and target sides are reversed
self.inverse_decoder = InverseDecoder(self.rng, self.n_in_src, 2*self.n_hids_src, self.n_hids_trg, \
# added by Zhaopeng Tu, 2016-06-09
with_attention=self.with_attention, \
maxout_part=self.maxout_part, name='rnn_inverse_decoder')
self.layers.append(self.inverse_decoder)
self.srng = RandomStreams(rng.randint(1e5))
self.inverse_logistic_layer = LogisticRegression(
self.rng,
self.n_in_src,
self.src_vocab_size,
name='inverse_LR')
self.layers.append(self.inverse_logistic_layer)
for layer in self.layers:
self.params.extend(layer.params)
def build_trainer(self, src, src_mask, src_hist, src_hist_mask, trg,
trg_mask, ite):
# added by Longyue
# checked by Zhaopeng: sentence dim = n_steps, hist_len, batch_size (4, 3, 25)
# hist = (bath_size, sent_num, sent_len) --.T-->
# hist = (sent_len, sent_num, bath_size) --lookup table-->
# (sent_len, sent_num, bath_size, word_emb) --reshape-->
# (sent_len, sent_num*bath_size, word_emb) --word-level rnn-->
# (sent_len, sent_num*bath_size, hidden_size) --reshape-->
# (sent_len, sent_num, bath_size, hidden_size) --[-1]-->
# (sent_num, bath_size, hidden_size) --sent-level rnn-->
# (sent_num, bath_size, hidden_size) --[-1]-->
# (bath_size, hidden_size) = cross-sent context vector
annotations_1 = self.encoder_hist_1.apply_1(src_hist, src_hist_mask)
annotations_1 = annotations_1[-1] # get last hidden states
annotations_2 = self.encoder_hist_2.apply_2(annotations_1)
annotations_3 = annotations_2[-1] # get last hidden states
#modified by Longyue
annotations = self.encoder.apply(src, src_mask, annotations_3)
# init_context = annotations[0, :, -self.n_hids_src:]
# modification #1
# mean pooling
init_context = (annotations *
src_mask[:, :, None]).sum(0) / src_mask.sum(0)[:, None]
#added by Longyue
init_context = concatenate([init_context, annotations_3],
axis=annotations_3.ndim - 1)
trg_emb = self.table_trg.apply(trg)
trg_emb_shifted = T.zeros_like(trg_emb)
trg_emb_shifted = T.set_subtensor(trg_emb_shifted[1:], trg_emb[:-1])
# modified by Longyue
hiddens, readout, alignment = self.decoder.run_pipeline(
state_below=trg_emb_shifted,
mask_below=trg_mask,
init_context=init_context,
c=annotations,
c_mask=src_mask,
hist=annotations_3)
# apply dropout
if self.dropout < 1.0:
logger.info('Apply dropout with p = {}'.format(self.dropout))
readout = Dropout(self.trng, readout, 1, self.dropout)
p_y_given_x = self.logistic_layer.get_probs(readout)
self.cost = self.logistic_layer.cost(p_y_given_x, trg,
trg_mask) / trg.shape[1]
# self.cost = theano.printing.Print('likilihood cost:')(self.cost)
# added by Zhaopeng Tu, 2016-07-12
# for reconstruction
if self.with_reconstruction:
# now hiddens is the annotations
inverse_init_context = (hiddens * trg_mask[:, :, None]
).sum(0) / trg_mask.sum(0)[:, None]
src_emb = self.table_src.apply(src)
src_emb_shifted = T.zeros_like(src_emb)
src_emb_shifted = T.set_subtensor(src_emb_shifted[1:],
src_emb[:-1])
inverse_hiddens, inverse_readout, inverse_alignment = self.inverse_decoder.run_pipeline(
state_below=src_emb_shifted,
mask_below=src_mask,
init_context=inverse_init_context,
c=hiddens,
c_mask=trg_mask)
# apply dropout
if self.dropout < 1.0:
# logger.info('Apply dropout with p = {}'.format(self.dropout))
inverse_readout = Dropout(self.srng, inverse_readout, 1,
self.dropout)
p_x_given_y = self.inverse_logistic_layer.get_probs(
inverse_readout)
self.reconstruction_cost = self.inverse_logistic_layer.cost(
p_x_given_y, src, src_mask) / src.shape[1]
# self.reconstruction_cost = theano.printing.Print('reconstructed cost:')(self.reconstruction_cost)
self.cost += self.reconstruction_cost * self.reconstruction_weight
self.L1 = sum(T.sum(abs(param)) for param in self.params)
self.L2 = sum(T.sum(param**2) for param in self.params)
params_regular = self.L1 * 1e-6 + self.L2 * 1e-6
# params_regular = theano.printing.Print('params_regular:')(params_regular)
# train cost
train_cost = self.cost + params_regular
# gradients
grads = T.grad(train_cost, self.params)
# apply gradient clipping here
grads = grad_clip(grads, self.clip_c)
# updates
updates = adadelta(self.params, grads)
# train function
# modified by Longyue
inps = [src, src_mask, src_hist, src_hist_mask, trg, trg_mask]
self.train_fn = theano.function(inps, [train_cost],
updates=updates,
name='train_function')
# self.train_fn = theano.function(inps, [train_cost], updates=updates, name='train_function', mode=NanGuardMode(nan_is_error=True, inf_is_error=True, big_is_error=True))
def build_sampler(self):
# added by Longyue
x_hist = T.ltensor3()
x_hist_mask = T.tensor3()
annotations_1 = self.encoder_hist_1.apply_1(x_hist, x_hist_mask)
annotations_1 = annotations_1[-1]
annotations_2 = self.encoder_hist_2.apply_2(annotations_1)
annotations_3 = annotations_2[-1]
x = T.lmatrix()
# Build Networks
# src_mask is None
c = self.encoder.apply(x, None, annotations_3)
#init_context = ctx[0, :, -self.n_hids_src:]
# mean pooling
init_context = c.mean(0)
# added by Longyue
init_context = concatenate([init_context, annotations_3],
axis=annotations_3.ndim - 1)
init_state = self.decoder.create_init_state(init_context)
outs = [init_state, c, annotations_3]
if not self.with_attention:
outs.append(init_context)
# compile function
print 'Building compile_init_state_and_context function ...'
self.compile_init_and_context = theano.function(
[x, x_hist, x_hist_mask], outs, name='compile_init_and_context')
print 'Done'
y = T.lvector()
cur_state = T.matrix()
# if it is the first word, emb should be all zero, and it is indicated by -1
trg_emb = T.switch(y[:, None] < 0, T.alloc(0., 1, self.n_in_trg),
self.table_trg.apply(y))
# added by Zhaopeng Tu, 2016-06-09
# for with_attention=False
if self.with_attention and self.with_coverage:
cov_before = T.tensor3()
if self.coverage_type is 'linguistic':
print 'Building compile_fertility ...'
fertility = self.decoder._get_fertility(c)
fertility = T.addbroadcast(fertility, 1)
self.compile_fertility = theano.function(
[c], [fertility], name='compile_fertility')
print 'Done'
else:
fertility = None
else:
cov_before = None
fertility = None
# apply one step
# modified by Zhaopeng Tu, 2016-04-29
# [next_state, ctxs] = self.decoder.apply(state_below=trg_emb,
results = self.decoder.apply(
state_below=trg_emb,
init_state=cur_state,
# added by Zhaopeng Tu, 2016-06-09
init_context=None if self.with_attention else init_context,
c=c if self.with_attention else None,
hist=annotations_3, # added by Longyue
one_step=True,
# added by Zhaopeng Tu, 2016-04-27
cov_before=cov_before,
fertility=fertility)
next_state = results[0]
if self.with_attention:
ctxs, alignment = results[1], results[2]
if self.with_coverage:
cov = results[3]
else:
# if with_attention=False, we always use init_context as the source representation
ctxs = init_context
readout = self.decoder.readout(next_state, ctxs, trg_emb)
# maxout
if self.maxout_part > 1:
readout = self.decoder.one_step_maxout(readout)
# apply dropout
if self.dropout < 1.0:
readout = Dropout(self.trng, readout, 0, self.dropout)
# compute the softmax probability
next_probs = self.logistic_layer.get_probs(readout)
# sample from softmax distribution to get the sample
next_sample = self.trng.multinomial(pvals=next_probs).argmax(1)
# compile function
print 'Building compile_next_state_and_probs function ...'
inps = [y, cur_state]
if self.with_attention:
inps.append(c)
else:
inps.append(init_context)
# added by Longyue
inps.append(annotations_3)
outs = [next_probs, next_state, next_sample]
# added by Zhaopeng Tu, 2016-06-09
if self.with_attention:
outs.append(alignment)
# added by Zhaopeng Tu, 2016-04-29
if self.with_coverage:
inps.append(cov_before)
if self.coverage_type is 'linguistic':
inps.append(fertility)
outs.append(cov)
self.compile_next_state_and_probs = theano.function(
inps, outs, name='compile_next_state_and_probs')
print 'Done'
# added by Zhaopeng Tu, 2016-07-18
# for reconstruction
if self.with_reconstruction:
# Build Networks
# trg_mask is None
inverse_c = T.tensor3()
# mean pooling
inverse_init_context = inverse_c.mean(0)
inverse_init_state = self.inverse_decoder.create_init_state(
inverse_init_context)
outs = [inverse_init_state]
if not self.with_attention:
outs.append(inverse_init_context)
# compile function
print 'Building compile_inverse_init_state_and_context function ...'
self.compile_inverse_init_and_context = theano.function(
[inverse_c], outs, name='compile_inverse_init_and_context')
print 'Done'
src = T.lvector()
inverse_cur_state = T.matrix()
trg_mask = T.matrix()
# if it is the first word, emb should be all zero, and it is indicated by -1
src_emb = T.switch(src[:, None] < 0, T.alloc(0., 1, self.n_in_src),
self.table_src.apply(src))
# apply one step
# modified by Zhaopeng Tu, 2016-04-29
inverse_results = self.inverse_decoder.apply(
state_below=src_emb,
init_state=inverse_cur_state,
# added by Zhaopeng Tu, 2016-06-09
init_context=None
if self.with_attention else inverse_init_context,
c=inverse_c if self.with_attention else None,
c_mask=trg_mask,
one_step=True)
inverse_next_state = inverse_results[0]
if self.with_attention:
inverse_ctxs, inverse_alignment = inverse_results[
1], inverse_results[2]
else:
# if with_attention=False, we always use init_context as the source representation
inverse_ctxs = init_context
inverse_readout = self.inverse_decoder.readout(
inverse_next_state, inverse_ctxs, src_emb)
# maxout
if self.maxout_part > 1:
inverse_readout = self.inverse_decoder.one_step_maxout(
inverse_readout)
# apply dropout
if self.dropout < 1.0:
inverse_readout = Dropout(self.srng, inverse_readout, 0,
self.dropout)
# compute the softmax probability
inverse_next_probs = self.inverse_logistic_layer.get_probs(
inverse_readout)
# sample from softmax distribution to get the sample
inverse_next_sample = self.srng.multinomial(
pvals=inverse_next_probs).argmax(1)
# compile function
print 'Building compile_inverse_next_state_and_probs function ...'
inps = [src, trg_mask, inverse_cur_state]
if self.with_attention:
inps.append(inverse_c)
else:
inps.append(inverse_init_context)
outs = [
inverse_next_probs, inverse_next_state, inverse_next_sample
]
# added by Zhaopeng Tu, 2016-06-09
if self.with_attention:
outs.append(inverse_alignment)
self.compile_inverse_next_state_and_probs = theano.function(
inps, outs, name='compile_inverse_next_state_and_probs')
print 'Done'
def save(self, path=None):
if path is None:
path = self.path
filenpz = open(path, "w")
val = dict([(value.name, value.get_value())
for index, value in enumerate(self.params)])
logger.info("save the model {}".format(path))
numpy.savez(path, **val)
filenpz.close()
def load(self, path=None):
if path is None:
path = self.path
if os.path.isfile(path):
logger.info("load params {}".format(path))
val = numpy.load(path)
for index, param in enumerate(self.params):
logger.info('Loading {} with shape {}'.format(
param.name,
param.get_value(borrow=True).shape))
if param.name not in val.keys():
logger.info('Adding new param {} with shape {}'.format(
param.name,
param.get_value(borrow=True).shape))
continue
if param.get_value().shape != val[param.name].shape:
logger.info("Error: model param != load param shape {} != {}".format(\
param.get_value().shape, val[param.name].shape))
raise Exception("loading params shape mismatch")
else:
param.set_value(val[param.name], borrow=True)
else:
logger.error("file {} does not exist".format(path))
self.save()
class EncoderDecoder(object):
def __init__(self, rng, **kwargs):
self.n_in_src = kwargs.get('nembed_src')
self.n_in_trg = kwargs.get('nembed_trg')
self.n_hids_src = kwargs.get('nhids_src')
self.n_hids_trg = kwargs.get('nhids_trg')
self.src_vocab_size = kwargs.get('src_vocab_size')
self.trg_vocab_size = kwargs.get('trg_vocab_size')
self.method = kwargs.get('method')
self.dropout = kwargs.get('dropout')
self.maxout_part = kwargs.get('maxout_part')
self.path = kwargs.get('saveto')
self.clip_c = kwargs.get('clip_c')
self.rng = rng
self.trng = RandomStreams(rng.randint(1e5))
# added by Zhaopeng Tu, 2016-04-29
self.with_coverage = kwargs.get('with_coverage')
self.coverage_dim = kwargs.get('coverage_dim')
self.coverage_type = kwargs.get('coverage_type')
self.max_fertility = kwargs.get('max_fertility')
if self.coverage_type is 'linguistic':
# make sure the dimension of linguistic coverage is always 1
self.coverage_dim = 1
# added by Zhaopeng Tu, 2016-05-30
self.with_context_gate = kwargs.get('with_context_gate')
# added by Zhaopeng Tu, 2017-11-29
self.with_layernorm = kwargs.get('with_layernorm', False)
self.params = []
self.layers = []
self.table_src = LookupTable(self.rng,
self.src_vocab_size,
self.n_in_src,
name='table_src')
self.layers.append(self.table_src)
self.encoder = BidirectionalEncoder(self.rng,
self.n_in_src,
self.n_hids_src,
self.table_src,
name='birnn_encoder')
self.layers.append(self.encoder)
self.table_trg = LookupTable(self.rng,
self.trg_vocab_size,
self.n_in_trg,
name='table_trg')
self.layers.append(self.table_trg)
self.decoder = Decoder(self.rng, self.n_in_trg, self.n_hids_trg, 2*self.n_hids_src, \
maxout_part=self.maxout_part, name='rnn_decoder', \
# added by Zhaopeng Tu, 2016-04-29
with_coverage=self.with_coverage, coverage_dim=self.coverage_dim, coverage_type=self.coverage_type, max_fertility=self.max_fertility, \
# added by Zhaopeng Tu, 2016-05-30
with_context_gate=self.with_context_gate, \
with_layernorm=self.with_layernorm)
self.layers.append(self.decoder)
self.logistic_layer = LogisticRegression(self.rng, self.n_in_trg,
self.trg_vocab_size)
self.layers.append(self.logistic_layer)
# added by Zhaopeng Tu, 2016-07-12
# for reconstruction
self.with_reconstruction = kwargs.get('with_reconstruction')
if self.with_reconstruction:
# added by Zhaopeng Tu, 2016-07-27
self.reconstruction_weight = kwargs.get('reconstruction_weight')
# note the source and target sides are reversed
self.inverse_decoder = Decoder(self.rng, self.n_in_src, 2*self.n_hids_src, self.n_hids_trg, \
maxout_part=self.maxout_part, name='rnn_inverse_decoder', \
with_layernorm=self.with_layernorm)
self.layers.append(self.inverse_decoder)
self.srng = RandomStreams(rng.randint(1e5))
self.inverse_logistic_layer = LogisticRegression(
self.rng,
self.n_in_src,
self.src_vocab_size,
name='inverse_LR')
self.layers.append(self.inverse_logistic_layer)
for layer in self.layers:
self.params.extend(layer.params)
def build_trainer(self, src, src_mask, trg, trg_mask):
annotations = self.encoder.apply(src, src_mask)
# init_context = annotations[0, :, -self.n_hids_src:]
# modification #1
# mean pooling
init_context = (annotations *
src_mask[:, :, None]).sum(0) / src_mask.sum(0)[:, None]
trg_emb = self.table_trg.apply(trg)
trg_emb_shifted = T.zeros_like(trg_emb)
trg_emb_shifted = T.set_subtensor(trg_emb_shifted[1:], trg_emb[:-1])
results = self.decoder.run_pipeline(state_below=trg_emb_shifted,
mask_below=trg_mask,
init_context=init_context,
c=annotations,
c_mask=src_mask)
hiddens, ctxs, readout, alignment = results[:4]
# apply dropout
if self.dropout < 1.0:
logger.info('Apply dropout with p = {}'.format(self.dropout))
readout = Dropout(self.trng, readout, 1, self.dropout)
p_y_given_x = self.logistic_layer.get_probs(readout)
self.cost = self.logistic_layer.cost(p_y_given_x, trg,
trg_mask) / trg.shape[1]
# self.cost = theano.printing.Print('likilihood cost:')(self.cost)
# added by Zhaopeng Tu, 2016-07-12
# for reconstruction
if self.with_reconstruction:
# now hiddens is the annotations
inverse_init_context = (hiddens * trg_mask[:, :, None]
).sum(0) / trg_mask.sum(0)[:, None]
src_emb = self.table_src.apply(src)
src_emb_shifted = T.zeros_like(src_emb)
src_emb_shifted = T.set_subtensor(src_emb_shifted[1:],
src_emb[:-1])
inverse_results = self.inverse_decoder.run_pipeline(
state_below=src_emb_shifted,
mask_below=src_mask,
init_context=inverse_init_context,
c=hiddens,
c_mask=trg_mask)
inverse_hiddens, inverse_ctxs, inverse_readout, inverse_alignment = inverse_results[:
4]
# apply dropout
if self.dropout < 1.0:
# logger.info('Apply dropout with p = {}'.format(self.dropout))
inverse_readout = Dropout(self.srng, inverse_readout, 1,
self.dropout)
p_x_given_y = self.inverse_logistic_layer.get_probs(
inverse_readout)
self.reconstruction_cost = self.inverse_logistic_layer.cost(
p_x_given_y, src, src_mask) / src.shape[1]
# self.reconstruction_cost = theano.printing.Print('reconstructed cost:')(self.reconstruction_cost)
self.cost += self.reconstruction_cost * self.reconstruction_weight
self.L1 = sum(T.sum(abs(param)) for param in self.params)
self.L2 = sum(T.sum(param**2) for param in self.params)
params_regular = self.L1 * 1e-6 + self.L2 * 1e-6
# params_regular = theano.printing.Print('params_regular:')(params_regular)
# train cost
train_cost = self.cost + params_regular
# gradients
grads = T.grad(train_cost, self.params)
# apply gradient clipping here
grads = grad_clip(grads, self.clip_c)
# train function
inps = [src, src_mask, trg, trg_mask]
outs = [train_cost]
if self.with_layernorm:
inps = [src, src_mask, trg, trg_mask]
lr = T.scalar(name='lr')
print 'Building optimizers...',
self.train_fn, self.update_fn = adam(lr, self.params, grads, inps,
outs)
else:
# updates
updates = adadelta(self.params, grads)
# mode=theano.Mode(linker='vm') for ifelse
# Unless linker='vm' or linker='cvm' are used, ifelse will compute both variables and take the same computation time as switch.
self.train_fn = theano.function(inps,
outs,
updates=updates,
name='train_function',
mode=theano.Mode(linker='vm'))
# self.train_fn = theano.function(inps, outs, updates=updates, name='train_function', mode=NanGuardMode(nan_is_error=True, inf_is_error=True, big_is_error=True))
def build_sampler(self):
x = T.lmatrix()
# Build Networks
# src_mask is None
c = self.encoder.apply(x, None)
#init_context = ctx[0, :, -self.n_hids_src:]
# mean pooling
init_context = c.mean(0)
init_state = self.decoder.create_init_state(init_context)
# compile function
print 'Building compile_init_state_and_context function ...'
self.compile_init_and_context = theano.function(
[x], [init_state, c], name='compile_init_and_context')
print 'Done'
y = T.lvector()
cur_state = T.matrix()
# if it is the first word, emb should be a1l zero, and it is indicated by -1
trg_emb = T.switch(y[:, None] < 0, T.alloc(0., 1, self.n_in_trg),
self.table_trg.apply(y))
# added by Zhaopeng Tu, 2016-06-09
if self.with_coverage:
cov_before = T.tensor3()
if self.coverage_type is 'linguistic':
print 'Building compile_fertility ...'
fertility = self.decoder._get_fertility(c)
fertility = T.addbroadcast(fertility, 1)
self.compile_fertility = theano.function(
[c], [fertility], name='compile_fertility')
print 'Done'
else:
fertility = None
else:
cov_before = None
fertility = None
# apply one step
# modified by Zhaopeng Tu, 2016-04-29
results = self.decoder.apply(
state_below=trg_emb,
init_state=cur_state,
c=c,
one_step=True,
# added by Zhaopeng Tu, 2016-04-27
cov_before=cov_before,
fertility=fertility)
next_state, ctxs, alignment = results[:3]
idx = 3
if self.with_coverage:
cov = results[idx]
idx += 1
readout = self.decoder.readout(next_state, ctxs, trg_emb)
# maxout
if self.maxout_part > 1:
readout = self.decoder.one_step_maxout(readout)
# apply dropout
if self.dropout < 1.0:
readout = Dropout(self.trng, readout, 0, self.dropout)
# compute the softmax probability
next_probs = self.logistic_layer.get_probs(readout)
# sample from softmax distribution to get the sample
next_sample = self.trng.multinomial(pvals=next_probs).argmax(1)
# compile function
print 'Building compile_next_state_and_probs function ...'
inps = [y, cur_state, c]
outs = [next_probs, next_state, next_sample, alignment]
# added by Zhaopeng Tu, 2016-04-29
if self.with_coverage:
inps.append(cov_before)
if self.coverage_type is 'linguistic':
inps.append(fertility)
outs.append(cov)
# mode=theano.Mode(linker='vm') for ifelse
# Unless linker='vm' or linker='cvm' are used, ifelse will compute both variables and take the same computation time as switch.
self.compile_next_state_and_probs = theano.function(
inps,
outs,
name='compile_next_state_and_probs',
mode=theano.Mode(linker='vm'))
print 'Done'
# added by Zhaopeng Tu, 2016-07-18
# for reconstruction
if self.with_reconstruction:
# Build Networks
# trg_mask is None
inverse_c = T.tensor3()
# mean pooling
inverse_init_context = inverse_c.mean(0)
inverse_init_state = self.inverse_decoder.create_init_state(
inverse_init_context)
outs = [inverse_init_state]
# compile function
print 'Building compile_inverse_init_state_and_context function ...'
self.compile_inverse_init_and_context = theano.function(
[inverse_c], outs, name='compile_inverse_init_and_context')
print 'Done'
src = T.lvector()
inverse_cur_state = T.matrix()
trg_mask = T.matrix()
# if it is the first word, emb should be all zero, and it is indicated by -1
src_emb = T.switch(src[:, None] < 0, T.alloc(0., 1, self.n_in_src),
self.table_src.apply(src))
# apply one step
# modified by Zhaopeng Tu, 2016-04-29
inverse_results = self.inverse_decoder.apply(
state_below=src_emb,
init_state=inverse_cur_state,
c=inverse_c,
c_mask=trg_mask,
one_step=True)
inverse_next_state, inverse_ctxs, inverse_alignment = inverse_results[:
3]
inverse_readout = self.inverse_decoder.readout(
inverse_next_state, inverse_ctxs, src_emb)
# maxout
if self.maxout_part > 1:
inverse_readout = self.inverse_decoder.one_step_maxout(
inverse_readout)
# apply dropout
if self.dropout < 1.0:
inverse_readout = Dropout(self.srng, inverse_readout, 0,
self.dropout)
# compute the softmax probability
inverse_next_probs, inverse_next_energy = self.inverse_logistic_layer.get_probs(
inverse_readout)
# sample from softmax distribution to get the sample
inverse_next_sample = self.srng.multinomial(
pvals=inverse_next_probs).argmax(1)
# compile function
print 'Building compile_inverse_next_state_and_probs function ...'
inps = [src, trg_mask, inverse_cur_state, inverse_c]
outs = [
inverse_next_probs, inverse_next_state, inverse_next_sample,
inverse_alignment
]
self.compile_inverse_next_state_and_probs = theano.function(
inps, outs, name='compile_inverse_next_state_and_probs')
print 'Done'
def save(self, path=None):
if path is None:
path = self.path
filenpz = open(path, "w")
val = dict([(value.name, value.get_value())
for index, value in enumerate(self.params)])
logger.info("save the model {}".format(path))
numpy.savez(path, **val)
filenpz.close()
def load(self, path=None):
if path is None:
path = self.path
if os.path.isfile(path):
logger.info("load params {}".format(path))
val = numpy.load(path)
for index, param in enumerate(self.params):
logger.info('Loading {} with shape {}'.format(
param.name,
param.get_value(borrow=True).shape))
if param.name not in val.keys():
logger.info('Adding new param {} with shape {}'.format(
param.name,
param.get_value(borrow=True).shape))
continue
if param.get_value().shape != val[param.name].shape:
logger.info("Error: model param != load param shape {} != {}".format(\
param.get_value().shape, val[param.name].shape))
raise Exception("loading params shape mismatch")
else:
param.set_value(val[param.name], borrow=True)
else:
logger.error("file {} does not exist".format(path))
self.save()