def _forward(self, emissions):
"""Viterbi forward to calculate all path scores.
:param emissions: List[dy.Expression]
Returns:
dy.Expression ((1,), B)
"""
init_alphas = [-1e4] * self.n_tags
init_alphas[self.start_idx] = 0
alphas = dy.inputVector(init_alphas)
transitions = self.transitions
# len(emissions) == T
for emission in emissions:
add_emission = dy.colwise_add(transitions, emission)
scores = dy.colwise_add(dy.transpose(add_emission), alphas)
# dy.logsumexp takes a list of dy.Expression and computes logsumexp
# elementwise across the lists so for example the logsumexp is calculated
# for [0] in each list. This means we want the scores for a given
# transition scores for a tag to be in the columns
alphas = dy.logsumexp([x for x in scores])
last_alpha = alphas + dy.pick(transitions, self.end_idx)
alpha = dy.logsumexp([x for x in last_alpha])
return alpha
def calc_attention(self, state):
V = dy.parameter(self.pV)
U = dy.parameter(self.pU)
WI = self.WI
curr_sent_mask = self.curr_sent.mask
if self.attention_vecs:
conv_feats = dy.conv2d(self.attention_vecs[-1],
self.pL,
stride=[1, 1],
is_valid=False)
conv_feats = dy.transpose(
dy.reshape(conv_feats,
(conv_feats.dim()[0][0], self.hidden_dim),
batch_size=conv_feats.dim()[1]))
h = dy.tanh(dy.colwise_add(WI + conv_feats, V * state))
else:
h = dy.tanh(dy.colwise_add(WI, V * state))
scores = dy.transpose(U * h)
if curr_sent_mask is not None:
scores = curr_sent_mask.add_to_tensor_expr(scores,
multiplicator=-100.0)
normalized = dy.softmax(scores)
self.attention_vecs.append(normalized)
return normalized
def softmax(x):
"""
Compute the softmax function in tensorflow.
You might find the tensorflow functions tf.exp, tf.reduce_max,
tf.reduce_sum, tf.expand_dims useful. (Many solutions are possible, so you may
not need to use all of these functions). Recall also that many common
tensorflow operations are sugared (e.g. x * y does a tensor multiplication
if x and y are both tensors). Make sure to implement the numerical stability
fixes as in the previous homework!
Args:
x: tf.Tensor with shape (n_samples, n_features). Note feature vectors are
represented by row-vectors. (For simplicity, no need to handle 1-d
input as in the previous homework)
Returns:
out: tf.Tensor with shape (n_sample, n_features). You need to construct this
tensor in this problem.
"""
### YOUR CODE HERE
x_max = dy.max_dim(x, 1)
x_sub = dy.colwise_add(x, -x_max)
x_exp = dy.exp(x_sub)
sum_exp = dy.colwise_add(dy.zeroes(x.dim()[0]), dy.sum_cols(x_exp))
out = dy.cdiv(x_exp, sum_exp)
### END YOUR CODE
return out
def hier_attend(self, context_pre, context_pos, state):
w2 = dy.parameter(self.hier_w2)
v = dy.parameter(self.hier_v)
w2dt = w2 * dy.concatenate(list(state.s()))
# context_pre
w1_pre = dy.parameter(self.hier_w1_pre)
w1dt_pre = w1_pre * context_pre
energy_pre = dy.transpose(v * dy.tanh(dy.colwise_add(w1dt_pre, w2dt)))
w_pre = dy.parameter(self.hier_w_pre)
wdt_pre = w_pre * context_pre
# context_pos
w1_pos = dy.parameter(self.hier_w1_pos)
w1dt_pos = w1_pos * context_pos
energy_pos = dy.transpose(v * dy.tanh(dy.colwise_add(w1dt_pos, w2dt)))
w_pos = dy.parameter(self.hier_w_pos)
wdt_pos = w_pos * context_pos
beta = dy.softmax(dy.concatenate([energy_pre, energy_pos]))
wdt = dy.concatenate_cols([wdt_pre, wdt_pos])
context = wdt * beta
return context
def _forward(self, emissions):
"""Viterbi forward to calculate all path scores.
:param emissions: List[dy.Expression]
Returns:
dy.Expression ((1,), B)
"""
init_alphas = [-1e4] * self.n_tags
init_alphas[self.start_idx] = 0
alphas = dy.inputVector(init_alphas)
transitions = self.transitions
# len(emissions) == T
for emission in emissions:
add_emission = dy.colwise_add(transitions, emission)
scores = dy.colwise_add(dy.transpose(add_emission), alphas)
# dy.logsumexp takes a list of dy.Expression and computes logsumexp
# elementwise across the lists so for example the logsumexp is calculated
# for [0] in each list. This means we want the scores for a given
# transition scores for a tag to be in the columns
alphas = dy.logsumexp([x for x in scores])
last_alpha = alphas + dy.pick(transitions, self.end_idx)
alpha = dy.logsumexp([x for x in last_alpha])
return alpha
def attend_with_prev(self, state, w1dt, prev_att):
w2dt = self.attention_w2 * state
w3dt = self.attention_w3 * prev_att
unnormalized = dy.transpose(
self.attention_v *
dy.tanh(dy.colwise_add(dy.colwise_add(w1dt, w2dt), w3dt)))
att_weights = dy.softmax(unnormalized)
return att_weights
def softmax(x):
### YOUR CODE HERE
x_max = dy.max_dim(x, 1)
x_sub = dy.colwise_add(x, -x_max)
x_exp = dy.exp(x_sub)
x_sum = dy.sum_cols(x_exp)
x_tmp = dy.zeroes(x.dim()[0])
x_tmp = dy.colwise_add(x_tmp, x_sum)
out = dy.cdiv(x_exp, x_tmp)
### END YOUR CODE
return out
def get_word_att(self, ut, l, s):
input_mat = dy.concatenate_cols(ut.words_enc)
unnormalized = dy.transpose(self.attention_word_v * dy.tanh(
dy.colwise_add(
dy.colwise_add(self.attention_word_w1 * input_mat,
self.attention_word_w2 * l),
self.attention_word_w3 * s)))
att_weights = dy.softmax(unnormalized)
ut.context = input_mat * att_weights
def transform(sentence):
w1 = dy.parameter(transform_w1)
b1 = dy.parameter(transform_b1)
w2 = dy.parameter(transform_w2)
b2 = dy.parameter(transform_b2)
sentence_transformed = dy.colwise_add(w1 * sentence, b1)
sentence_transformed = dy.rectify(sentence_transformed)
sentence_transformed = dy.colwise_add(w2 * sentence_transformed, b2)
sentence_transformed = dy.rectify(sentence_transformed)
return sentence_transformed
def __attention_mlp(self, H_f, h_e, W1_att_e, W1_att_f, w2_att,
W1_att_lang, langeb):
# Calculate the alignment score vector
a_t = dy.tanh(
dy.colwise_add(dy.colwise_add(W1_att_f * H_f, W1_att_e * h_e),
W1_att_lang * langeb))
a_t = w2_att * a_t
a_t = a_t[0]
alignment = dy.softmax(a_t)
c_t = H_f * alignment
return c_t
def __attention_mlp_batch(self, H_f_batch, h_e_batch, W1_att_e, W1_att_f,
w2_att, W1_att_lang, langeb):
# H_f_batch: (2 * hidden_size, num_step, batch_size)
# h_e_batch: (hidden_size, batch_size)
a_t_batch = dy.tanh(
dy.colwise_add(
dy.colwise_add(W1_att_f * H_f_batch,
W1_att_e * h_e_batch), W1_att_lang *
langeb)) # (attention_size, num_step, batch_size)
a_t_batch = w2_att * a_t_batch # (1, num_step, batch_size)
a_t_batch = a_t_batch[0] # (num_step, batch_size)
alignment_batch = dy.softmax(a_t_batch) # (num_step, batch_size)
c_t_batch = H_f_batch * alignment_batch # (2 * hidden_size, batch_size)
return c_t_batch
def get_v1_v2(alpha, beta, sen1, sen2, model_params):
G_w1 = model_params['G_w1']
G_b1 = model_params['G_b1']
G_w2 = model_params['G_w2']
G_b2 = model_params['G_b2']
con = dy.concatenate([sen1, beta], d=0)
#con = dy.dropout(con, DROPOUT_RATE)
v1 = dy.rectify(G_w2 * (dy.rectify(dy.colwise_add(G_w1 * con, G_b1))) + G_b2)
con = dy.concatenate([sen2, alpha], d=0)
#con = dy.dropout(con, DROPOUT_RATE)
v2 = dy.rectify(G_w2 * (dy.rectify(dy.colwise_add(G_w1 * con, G_b1))) + G_b2)
return v1, v2
def set_E_matrix(sen1, sen2, model_params):
F_w1 = model_params['F_w1']
F_b1 = model_params['F_b1']
F_w2 = model_params['F_w2']
F_b2 = model_params['F_b2']
#sen1 = dy.dropout(sen1, DROPOUT_RATE)
#sen2 = dy.dropout(sen2, DROPOUT_RATE)
F_sen1 = dy.rectify(F_w2 * (dy.rectify(dy.colwise_add(F_w1*sen1, F_b1))) + F_b2)
F_sen2 = dy.rectify(F_w2 * (dy.rectify(dy.colwise_add(F_w1*sen2, F_b1))) + F_b2)
E_matrix = (dy.transpose(F_sen1)) * F_sen2
return E_matrix, F_sen1, F_sen2
def calc_attention(self, src_trans_att, h_t, training=True):
with parameters(self.W_h, self.U, trainable=training) as (W_h, U):
att_hidden = dy.tanh(dy.colwise_add(src_trans_att, W_h * h_t))
att_weights = dy.transpose(U * att_hidden)
att_weights = dy.softmax(att_weights)
return att_weights
def attend(self, encodings, h):
"""Compute attention score
Given :math:`z_i` the encoder's output at time :math:`i`, :math:`h_{j-1}` the decoder's output at time :math:`j-1`, the attention score is computed as :
.. math::
\begin{split}
s_{ij}&=V_a^T\tanh(W_az_i + W_{ha}h_j + b_a)\\
\alpha_{ij}&=\frac{s_{ij}}{\sum_{i'}s_{i'j}}\\
\end{split}
Arguments:
encodings (dynet.Expression): Source sentence encodings obtained with self.encode
h (dynet.Expression): Decoder output at the previous timestep
Returns:
tuple: Two dynet Expressions, the context and the attention weights
"""
Va, Wa, Wha = self.Va_p.expr(), self.Wa_p.expr(), self.Wha_p.expr()
d = dy.tanh(dy.colwise_add(Wa * encodings, Wha * h))
scores = dy.transpose(d) * Va
weights = dy.softmax(scores)
context = encodings * weights
return context, weights
def decode(self, emissions):
"""Viterbi decode to find the best sequence.
:param emissions: List[dy.Expression]
Returns:
List[int], dy.Expression ((1,), B)
"""
if self.add_ends:
emissions = CRF._prep_input(emissions)
backpointers = []
transitions = self.transitions
inits = [-1e4] * self.n_tags
inits[self.start_idx] = 0
alphas = dy.inputVector(inits)
for emission in emissions:
next_vars = dy.colwise_add(dy.transpose(transitions), alphas)
best_tags = np.argmax(next_vars.npvalue(), 0)
v_t = dy.max_dim(next_vars, 0)
alphas = v_t + emission
backpointers.append(best_tags)
terminal_expr = alphas + dy.pick(transitions, self.end_idx)
best_tag = np.argmax(terminal_expr.npvalue())
path_score = dy.pick(terminal_expr, best_tag)
best_path = [best_tag]
for bp_t in reversed(backpointers):
best_tag = bp_t[best_tag]
best_path.append(best_tag)
_ = best_path.pop()
best_path.reverse()
return best_path, path_score
def attend_tags(self, state, w1dt):
w2dt = self.tag_attention_w2 * state
unnormalized = dy.transpose(self.tag_attention_v *
dy.tanh(dy.colwise_add(w1dt, w2dt)))
att_weights = dy.softmax(unnormalized)
return att_weights
def attend(self, w1dt, vectors,state):
import time
start = time.time()
if debug:
print "In attention"
w2 = dy.parameter(self.attention_w2)
v = dy.parameter(self.attention_v)
if debug:
print "Shape of w2: ", np.asarray(w2.value()).shape
print "Shape of state : " , np.asarray(dy.concatenate(list(state.s())).value()).shape
end = time.time()
start = end
w2dt = w2 * dy.concatenate(list(state.s()))
end = time.time()
if debug:
print " Shape of W2dt: ", np.asarray(w2dt.value()).shape
unnormalized = dy.transpose(v * dy.tanh(dy.colwise_add(w1dt, w2dt)))
if debug:
print "Shape of unnormalized: ", np.asarray(unnormalized.value()).shape
end = time.time()
att_weights = dy.softmax(unnormalized)
if debug:
print "Shape of Attention weights: ", np.asarray(att_weights.value()).shape
end = time.time()
context = vectors * att_weights
if debug:
print "Shape of context: ", np.asarray(context.value()).shape
#print "Context: " , np.asarray(context.value())
return context
def generate(self, h_a, trg, maxlen=100):
#decode(self, h_a, trg, decorate=False):
h_a += ([dy.zeros(self.hdim)] * (self.max_len - len(h_a))
) #padding to make equal to maxlength
h_ak = dy.concatenate(h_a, 1)
#pdb.set_trace()
pre_attend = dy.parameter(self.pre_attend)
context = h_ak * pre_attend
prev_out = dy.zeros((self.hdim))
outputs = []
s = self.decoder_rnn.initial_state()
for i in range(maxlen):
attender = dy.parameter(self.attender)
#pdb.set_trace()
V = dy.parameter(self.v)
tmp = dy.tanh(dy.colwise_add(context, V * prev_out))
U = dy.parameter(self.u)
attention_weights = dy.softmax(dy.transpose(U * tmp))
#pdb.set_trace()
emb = dy.concatenate([h_ak * attention_weights, prev_out])
s = s.add_input(emb)
prev_out = s.output()
pre2 = dy.parameter(self.pred)
pre2 * prev_out
outputs.append(pre2 * prev_out)
act_value = pre2 * prev_out
act_value = np.argmax(act_value.value())
outputs.append(act_value)
if act_value == 1:
return outputs
return outputs
def attend(input_mat, state, w1dt_array):
# Takes in [l * 2hE * n], [l * 2hD * n], [l * a * n] as input and returns [l * a * n] as output
global attention_w2
global attention_v
w2 = dy.parameter(attention_w2)
v = dy.parameter(attention_v)
if debug_dimensions:
print "In attention "
print " Dimensions of input mat are : ", get_tensor_size(input_mat)
print " Dimensions of w1dt array: ", get_tensor_size(w1dt_array)
print " Dimensions of state ", len(state)
# Get w2dt = weight matrix * decoder state output
w2dt_array = []
for s in state:
w2dt = w2*dy.concatenate(list(s.s()))
w2dt_array.append(w2dt)
if debug_dimensions:
print " Dimensions of w2dt array: ", get_tensor_size(w2dt_array)
unnormalized_array = []
att_weights_array = []
for (a,b) in zip(w1dt_array, w2dt_array):
unnormalized = dy.transpose(v * dy.tanh(dy.colwise_add(a,b)))
att_weights = dy.softmax(unnormalized)
att_weights_array.append(att_weights)
if debug_dimensions:
print " Dimensions of attention weights array: ", get_tensor_size(att_weights_array)
context_array = []
for (im, at) in zip(input_mat, att_weights_array):
context = im * at
context_array.append(context)
if debug_dimensions:
print " Dimensions of contexts array: ", get_tensor_size(context_array)
return context_array
def cal_scores(self, s):
if len(self.ps) == 0:
return None
hs_matrix = dy.tanh(
dy.colwise_add(dy.concatenate_cols(self.ps),
W * s))
return dy.softmax(dy.transpose(b * hs_matrix))
def _vaswani_model_scores(m):
out_c2 = dy.rectify(
dy.colwise_add(c2_Wlm * m["beam_lm_hs"],
dy.pick(m["aux_c2"], m["idx"], 1)))
# if cfg["use_beam_bilstm"]:
# _, beam_size_prev = out_c2.dim()[0]
# beam_hs = [dy.pick(out_c2, i, 1) for i in xrange(beam_size_prev)]
# bf_init = b_fwd.initial_state()
# bb_init = b_bwd.initial_state()
# bf_hs = dy.concatenate_cols(bf_init.transduce(beam_hs))
# bb_hs = dy.concatenate_cols(bb_init.transduce(reversed(beam_hs))[::-1])
# out_c2 = dy.concatenate([bf_hs, bb_hs])
# if cfg["use_beam_mlp"]:
# out_b = dy.max_dim(b_W1 * out_c2 + b_b1, 1)
# out_c2 = dy.colwise_add(out_c2, dy.rectify(b_W2 * out_b + b_b2))
scores = o_W * out_c2 + o_b
scores = dy.transpose(scores)
if cfg["accumulate_scores"]:
scores = m["acc_scores"] + scores
m["scores"] = scores
return scores
def viterbi(emissions, transition, start_idx, end_idx, norm=False):
n_tags = emissions[0].dim()[0][0]
backpointers = []
inits = [-1e4] * n_tags
inits[start_idx] = 0
alphas = dy.inputVector(inits)
alphas = dy.log_softmax(alphas) if norm else alphas
for emission in emissions:
next_vars = dy.colwise_add(dy.transpose(transition), alphas)
best_tags = np.argmax(next_vars.npvalue(), 0)
v_t = dy.max_dim(next_vars, 0)
alphas = v_t + emission
backpointers.append(best_tags)
terminal_expr = alphas + dy.pick(transition, end_idx)
best_tag = np.argmax(terminal_expr.npvalue())
path_score = dy.pick(terminal_expr, best_tag)
best_path = [best_tag]
for bp_t in reversed(backpointers):
best_tag = bp_t[best_tag]
best_path.append(best_tag)
_ = best_path.pop()
best_path.reverse()
return best_path, path_score
def attend(self, enc_h_ts_mat, dec_h_t, encatt, store_weights=False):
"""
Parameters:
-----------
enc_h_ts_mat: dynet.Expression, (seq_len x enc_hid_dim)
matrix of encoding hidden state column vectors
dec_h_t: dynet.RNNState, (dec_hid_dim)
current decoder hidden state
encatt: dynet.Expression, (seq_len x att_dim)
projection of the encoder hidden states into the attention space
store_weights: bool,
whether to store attention weights
"""
dec2att = dy.parameter(self.dec2att)
att_v = dy.parameter(self.att_v)
# project output of last hidden layer (state.h()[-1] == state.output())
# to the dimensionality of the attention space
decatt = dec2att * dec_h_t.output()
# projection vector att_v
# unnormalized var-len alignment vector (with len == source seq len)
# (seq_len)
unnormalized_weights = att_v * dy.tanh(dy.colwise_add(encatt, decatt))
weights = dy.softmax(dy.transpose(unnormalized_weights))
if store_weights:
self.current_weights.append(weights.value())
context = enc_h_ts_mat * weights
return context
def combine(sentence, sentence_other_attended):
w1 = dy.parameter(combine_w1)
b1 = dy.parameter(combine_b1)
w2 = dy.parameter(combine_w2)
b2 = dy.parameter(combine_b2)
sentence_combine = dy.concatenate([sentence, sentence_other_attended], d=0)
logging.debug("Sentence combined with Attended shape: " +
str(sentence_combine.dim()))
combine_transformed = dy.colwise_add(w1 * sentence_combine, b1)
combine_transformed = dy.rectify(combine_transformed)
combine_transformed = dy.colwise_add(w2 * combine_transformed, b2)
combine_transformed = dy.rectify(combine_transformed)
return combine_transformed
def viterbi(emissions, transition, start_idx, end_idx, norm=False):
n_tags = emissions[0].dim()[0][0]
backpointers = []
inits = [-1e4] * n_tags
inits[start_idx] = 0
alphas = dy.inputVector(inits)
alphas = dy.log_softmax(alphas) if norm else alphas
for emission in emissions:
next_vars = dy.colwise_add(dy.transpose(transition), alphas)
best_tags = np.argmax(next_vars.npvalue(), 0)
v_t = dy.max_dim(next_vars, 0)
alphas = v_t + emission
backpointers.append(best_tags)
terminal_expr = alphas + dy.pick(transition, end_idx)
best_tag = np.argmax(terminal_expr.npvalue())
path_score = dy.pick(terminal_expr, best_tag)
best_path = [best_tag]
for bp_t in reversed(backpointers):
best_tag = bp_t[best_tag]
best_path.append(best_tag)
_ = best_path.pop()
best_path.reverse()
return best_path, path_score
def calc_attention(src_output_matrix, tgt_output_embedding, fixed_attentional_component):
w1_att_src = dy.parameter(w1_att_src_p)
w1_att_tgt = dy.parameter(w1_att_tgt_p)
w2_att = dy.parameter(w2_att_p)
a_t = dy.transpose(dy.tanh(dy.colwise_add(fixed_attentional_component, w1_att_tgt * tgt_output_embedding))) * w2_att
alignment = dy.softmax(a_t)
att_output = src_output_matrix * alignment
return att_output, alignment
def calc_attention(src_output_matrix, tgt_output_embedding, fixed_attentional_component):
w1_att_src = dy.parameter(w1_att_src_p)
w1_att_tgt = dy.parameter(w1_att_tgt_p)
w2_att = dy.parameter(w2_att_p)
a_t = dy.transpose(dy.tanh(dy.colwise_add(fixed_attentional_component, w1_att_tgt * tgt_output_embedding))) * w2_att
alignment = dy.softmax(a_t)
att_output = src_output_matrix * alignment
return att_output, alignment
def calc_attention(self, state):
V = dy.parameter(self.pV)
U = dy.parameter(self.pU)
h = dy.tanh(dy.colwise_add(self.WI, V * state))
scores = dy.transpose(U * h)
return dy.softmax(scores)
def attend(self, input_mat, state, w1dt):
w2 = dy.parameter(self.attention_w2)
v = dy.parameter(self.attention_v)
w2dt = w2 * dy.concatenate(list(state.s()))
att_weights = dy.softmax(
dy.transpose(v * dy.tanh(dy.colwise_add(w1dt, w2dt))))
context = input_mat * att_weights
return context
def get_utt_att(self, uts, s):
input_mat = dy.concatenate_cols([u.utt_enc for u in uts])
unnormalized = dy.transpose(self.attention_word_v * dy.tanh(
dy.colwise_add(self.attention_utt_w1 * input_mat,
self.attention_utt_w2 * s)))
att_weights = dy.softmax(unnormalized)
return input_mat * att_weights
def _attend(self, query, mask=None):
# query ((H), B)
# mask ((T, 1), B)
projected_state = self.decoder * query # ((H,), B)
non_lin = dy.tanh(dy.colwise_add(self.context_proj, projected_state)) # ((H, T), B)
attn_scores = dy.transpose(self.v * non_lin) # ((1, H), B) * ((H, T), B) -> ((1, T), B) -> ((T, 1), B)
if mask is not None:
attn_scores = dy.cmult(attn_scores, mask[0]) + (mask[1] * dy.scalarInput(-1e9))
return dy.softmax(attn_scores) # ((T, 1), B)
def calc_attention(self, state):
V = dy.parameter(self.pV)
U = dy.parameter(self.pU)
h = dy.tanh(dy.colwise_add(self.WI, V * state))
scores = dy.transpose(U * h)
normalized = dy.softmax(scores)
self.attention_vecs.append(normalized)
return normalized
def __attention_mlp(self, h_fs_matrix, h_e, fixed_attentional_component):
W1_att_e = dy.parameter(self.W1_att_e)
w2_att = dy.parameter(self.w2_att)
a_t = dy.transpose(
dy.tanh(dy.colwise_add(fixed_attentional_component,
W1_att_e * h_e))) * w2_att
alignment = dy.softmax(a_t)
c_t = h_fs_matrix * alignment
return c_t
def attend(input_mat, state, w1dt):
global attention_w2
global attention_v
w2 = dy.parameter(attention_w2)
v = dy.parameter(attention_v)
# input_mat: (encoder_state x seqlen) => input vecs concatenated as cols
# w1dt: (attdim x seqlen)
# w2dt: (attdim x attdim)
w2dt = w2*dy.concatenate(list(state.s()))
# att_weights: (seqlen,) row vector
unnormalized = dy.transpose(v * dy.tanh(dy.colwise_add(w1dt, w2dt)))
att_weights = dy.softmax(unnormalized)
# context: (encoder_state)
context = input_mat * att_weights
return context
def cal_scores(self, src_encodings):
src_len = len(src_encodings)
src_encodings = dy.concatenate_cols(src_encodings) # src_ctx_dim, src_len, batch_size
W_arc_hidden_to_head = dy.parameter(self.W_arc_hidden_to_head)
b_arc_hidden_to_head = dy.parameter(self.b_arc_hidden_to_head)
W_arc_hidden_to_dep = dy.parameter(self.W_arc_hidden_to_dep)
b_arc_hidden_to_dep = dy.parameter(self.b_arc_hidden_to_dep)
W_label_hidden_to_head = dy.parameter(self.W_label_hidden_to_head)
b_label_hidden_to_head = dy.parameter(self.b_label_hidden_to_head)
W_label_hidden_to_dep = dy.parameter(self.W_label_hidden_to_dep)
b_label_hidden_to_dep = dy.parameter(self.b_label_hidden_to_dep)
U_arc_1 = dy.parameter(self.U_arc_1)
u_arc_2 = dy.parameter(self.u_arc_2)
U_label_1 = [dy.parameter(x) for x in self.U_label_1]
u_label_2_1 = [dy.parameter(x) for x in self.u_label_2_1]
u_label_2_2 = [dy.parameter(x) for x in self.u_label_2_2]
b_label = [dy.parameter(x) for x in self.b_label]
h_arc_head = dy.rectify(dy.affine_transform([b_arc_hidden_to_head, W_arc_hidden_to_head, src_encodings])) # n_arc_ml_units, src_len, bs
h_arc_dep = dy.rectify(dy.affine_transform([b_arc_hidden_to_dep, W_arc_hidden_to_dep, src_encodings]))
h_label_head = dy.rectify(dy.affine_transform([b_label_hidden_to_head, W_label_hidden_to_head, src_encodings]))
h_label_dep = dy.rectify(dy.affine_transform([b_label_hidden_to_dep, W_label_hidden_to_dep, src_encodings]))
h_arc_head_transpose = dy.transpose(h_arc_head)
h_label_head_transpose = dy.transpose(h_label_head)
s_arc = h_arc_head_transpose * dy.colwise_add(U_arc_1 * h_arc_dep, u_arc_2)
s_label = []
for U_1, u_2_1, u_2_2, b in zip(U_label_1, u_label_2_1, u_label_2_2, b_label):
e1 = h_label_head_transpose * U_1 * h_label_dep
e2 = h_label_head_transpose * u_2_1 * dy.ones((1, src_len))
e3 = dy.ones((src_len, 1)) * u_2_2 * h_label_dep
s_label.append(e1 + e2 + e3 + b)
return s_arc, s_label
