def testSequenceLoss(self):
with self.test_session() as sess:
logits = [constant_op.constant(i + 0.5, shape=[2, 5]) for i in range(3)]
targets = [
constant_op.constant(
i, dtypes.int32, shape=[2]) for i in range(3)
]
weights = [constant_op.constant(1.0, shape=[2]) for i in range(3)]
average_loss_per_example = seq2seq_lib.sequence_loss(
logits,
targets,
weights,
average_across_timesteps=True,
average_across_batch=True)
res = sess.run(average_loss_per_example)
self.assertAllClose(1.60944, res)
average_loss_per_sequence = seq2seq_lib.sequence_loss(
logits,
targets,
weights,
average_across_timesteps=False,
average_across_batch=True)
res = sess.run(average_loss_per_sequence)
self.assertAllClose(4.828314, res)
total_loss = seq2seq_lib.sequence_loss(
logits,
targets,
weights,
average_across_timesteps=False,
average_across_batch=False)
res = sess.run(total_loss)
self.assertAllClose(9.656628, res)
def testSequenceLoss(self):
with self.test_session() as sess:
logits = [constant_op.constant(i + 0.5, shape=[2, 5]) for i in range(3)]
targets = [
constant_op.constant(
i, dtypes.int32, shape=[2]) for i in range(3)
]
weights = [constant_op.constant(1.0, shape=[2]) for i in range(3)]
average_loss_per_example = seq2seq_lib.sequence_loss(
logits,
targets,
weights,
average_across_timesteps=True,
average_across_batch=True)
res = sess.run(average_loss_per_example)
self.assertAllClose(1.60944, res)
average_loss_per_sequence = seq2seq_lib.sequence_loss(
logits,
targets,
weights,
average_across_timesteps=False,
average_across_batch=True)
res = sess.run(average_loss_per_sequence)
self.assertAllClose(4.828314, res)
total_loss = seq2seq_lib.sequence_loss(
logits,
targets,
weights,
average_across_timesteps=False,
average_across_batch=False)
res = sess.run(total_loss)
self.assertAllClose(9.656628, res)
def get_model(feed_previous=False):
learning_rate = tf.Variable(float(init_learning_rate), trainable=False, dtype=tf.float32)
learning_rate_decay_op = learning_rate.assign(learning_rate * 0.9)
encoder_inputs = []
decoder_inputs = []
target_weights = []
for i in range(input_seq_len):
encoder_inputs.append(tf.placeholder(tf.int32, shape=[None], name="encoder{0}".format(i)))
for i in range(output_seq_len + 1):
decoder_inputs.append(tf.placeholder(tf.int32, shape=[None], name="decoder{0}".format(i)))
for i in range(output_seq_len):
target_weights.append(tf.placeholder(tf.float32, shape=[None], name="weight{0}".format(i)))
targets = [decoder_inputs[i + 1] for i in range(output_seq_len)]
cell = tf.contrib.rnn.BasicLSTMCell(size)
outputs, _ = seq2seq.embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs[:output_seq_len],
cell,
num_encoder_symbols=num_encoder_symbols,
num_decoder_symbols=num_decoder_symbols,
embedding_size=size,
output_projection=None,
feed_previous=feed_previous,
dtype=tf.float32)
loss = seq2seq.sequence_loss(outputs, targets, target_weights)
opt = tf.train.GradientDescentOptimizer(learning_rate)
update = opt.apply_gradients(opt.compute_gradients(loss))
saver = tf.train.Saver(tf.global_variables())
return encoder_inputs, decoder_inputs, target_weights, outputs, loss, update, saver, learning_rate_decay_op, learning_rate
def get_model(feed_previous=False):
"""构造模型
"""
learning_rate = tf.Variable(float(init_learning_rate),
trainable=False,
dtype=tf.float32)
learning_rate_decay_op = learning_rate.assign(learning_rate * 0.9)
encoder_inputs = []
decoder_inputs = []
target_weights = []
for i in range(input_seq_len):
encoder_inputs.append(
tf.placeholder(tf.int32, shape=[None],
name="encoder{0}".format(i)))
for i in range(output_seq_len + 1):
decoder_inputs.append(
tf.placeholder(tf.int32, shape=[None],
name="decoder{0}".format(i)))
for i in range(output_seq_len):
target_weights.append(
tf.placeholder(tf.float32,
shape=[None],
name="weight{0}".format(i)))
# decoder_inputs左移一个时序作为targets
targets = [decoder_inputs[i + 1] for i in range(output_seq_len)]
# cell = tf.contrib.rnn.BasicLSTMCell(size)
dropout = 1
num_layers = 3
cell = tf.contrib.rnn.BasicLSTMCell(size)
cell = tf.contrib.rnn.DropoutWrapper(cell, output_keep_prob=dropout)
cell = tf.contrib.rnn.MultiRNNCell([cell] * num_layers) # 纵向上有两个LSTM
# 这里输出的状态我们不需要
outputs, _ = seq2seq.embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs[:output_seq_len],
cell,
num_encoder_symbols=num_encoder_symbols,
num_decoder_symbols=num_decoder_symbols,
embedding_size=size,
output_projection=None,
feed_previous=feed_previous,
dtype=tf.float32)
# 计算加权交叉熵损失
loss = seq2seq.sequence_loss(outputs, targets, target_weights)
# 梯度下降优化器
opt = tf.train.AdamOptimizer(learning_rate).minimize(loss)
# 优化目标：让loss最小化
# update = opt.apply_gradients(opt.compute_gradients(loss))
# 模型持久化
saver = tf.train.Saver(tf.global_variables())
return encoder_inputs, decoder_inputs, target_weights, outputs, loss, opt, saver, learning_rate_decay_op, learning_rate
def get_model(feed_previous=False):
"""
构造模型:seq2seq
feed_previous表示decoder_inputs是我们直接提供训练数据的输入，
还是用前一个RNNCell的输出映射出来的，如果feed_previous为True，
那么就是用前一个RNNCell的输出，并经过Wx+b线性变换成
"""
learning_rate = tf.Variable(float(init_learning_rate),
trainable=False,
dtype=tf.float32)
learning_rate_decay_op = learning_rate.assign(learning_rate * 0.9)
encoder_inputs = []
decoder_inputs = []
target_weights = []
for i in range(input_seq_len):
encoder_inputs.append(
tf.placeholder(tf.int32, shape=[None],
name="encoder{0}".format(i)))
for i in range(output_seq_len + 1):
decoder_inputs.append(
tf.placeholder(tf.int32, shape=[None],
name="decoder{0}".format(i)))
for i in range(output_seq_len):
target_weights.append(
tf.placeholder(tf.float32,
shape=[None],
name="weight{0}".format(i)))
# decoder_inputs左移一个时序作为targets
targets = [decoder_inputs[i + 1] for i in range(output_seq_len)]
cell = tf.contrib.rnn.BasicLSTMCell(size)
# 这里输出的状态我们不需要
outputs, _ = seq2seq.embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs[:output_seq_len],
cell,
num_encoder_symbols=num_encoder_symbols,
num_decoder_symbols=num_decoder_symbols,
embedding_size=size,
output_projection=None,
feed_previous=feed_previous,
dtype=tf.float32)
# 计算加权交叉熵损失
loss = seq2seq.sequence_loss(outputs, targets, target_weights)
# 梯度下降优化器
opt = tf.train.GradientDescentOptimizer(learning_rate)
# 优化目标：让loss最小化
update = opt.apply_gradients(opt.compute_gradients(loss))
# 模型持久化
saver = tf.train.Saver(tf.global_variables())
return encoder_inputs, decoder_inputs, target_weights, outputs, loss, update, saver, learning_rate_decay_op, learning_rate
def ForwardBackward(enc_inp, dec_inp, feed_previous):
scope_name = "fp_{}".format(feed_previous)
with variable_scope.variable_scope(scope_name):
dec_op, _ = seq2seq(enc_inp, dec_inp, feed_previous=feed_previous)
net_variables = ops.get_collection(ops.GraphKeys.GLOBAL_VARIABLES,
scope_name)
optimizer = adam.AdamOptimizer(0.03, epsilon=1e-5)
update_op = optimizer.minimize(
seq2seq_lib.sequence_loss(dec_op, targets, weights),
var_list=net_variables)
return dec_op, update_op, net_variables
def ForwardBackward(enc_inp, dec_inp, feed_previous):
scope_name = "fp_{}".format(feed_previous)
with variable_scope.variable_scope(scope_name):
dec_op, _ = seq2seq(enc_inp, dec_inp, feed_previous=feed_previous)
net_variables = ops.get_collection(ops.GraphKeys.GLOBAL_VARIABLES,
scope_name)
optimizer = adam.AdamOptimizer(0.03, epsilon=1e-5)
update_op = optimizer.minimize(
seq2seq_lib.sequence_loss(dec_op, targets, weights),
var_list=net_variables)
return dec_op, update_op, net_variables
def get_model(feed_previous=False):
learning_rate = tf.Variable(float(init_learning_rate),
trainable=False,
dtype=tf.float32)
learning_rate_decay_op = learning_rate.assign(learning_rate * 0.9)
encoder_inputs = []
decoder_inputs = []
target_weights = []
for i in range(input_seq_len):
encoder_inputs.append(
tf.compat.v1.placeholder(tf.int32,
shape=[None],
name="encoder{0}".format(i)))
for i in range(output_seq_len + 1):
decoder_inputs.append(
tf.compat.v1.placeholder(tf.int32,
shape=[None],
name="decoder{0}".format(i)))
for i in range(output_seq_len):
target_weights.append(
tf.compat.v1.placeholder(tf.float32,
shape=[None],
name="weight{0}".format(i)))
# decoder_inputs左移一个时序作为targets
targets = [decoder_inputs[i + 1] for i in range(output_seq_len)]
cell = tf.contrib.rnn.BasicLSTMCell(size)
# 这里输出的状态我们不需要
outputs, _ = seq2seq.embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs[:output_seq_len],
cell,
num_encoder_symbols=num_encoder_symbols,
num_decoder_symbols=num_decoder_symbols,
embedding_size=size,
output_projection=None,
# 是一个(W, B)结构的tuple，W是shape为[output_size x num_decoder_symbols]的weight矩阵，B是shape为[num_decoder_symbols]的偏置向量
feed_previous=feed_previous,
dtype=tf.float32)
# 计算交叉熵损失
loss = seq2seq.sequence_loss(outputs, targets, target_weights)
# 梯度下降优化器
opt = tf.compat.v1.train.GradientDescentOptimizer(learning_rate)
# 优化目标：让loss最小化
update = opt.apply_gradients(opt.compute_gradients(loss))
# 模型持久化,保存所有的变量
saver = tf.compat.v1.train.Saver(tf.compat.v1.global_variables())
return encoder_inputs, decoder_inputs, target_weights, outputs, loss, update, saver, learning_rate_decay_op, learning_rate
def get_model():
# 这个方法需要的参数分别是：inputs_tensor,decoder_tensor,cell,类似与vocab_size的symbols,虽然我不知道encoder_symbolsy有什么用
# 然后是embed_size，应该和cell的size一样，然后是需不需要softmax，decode_inputs是来自前面的RNNcell还是我们自己输入，最后是数
# 据类型
'''
embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs,
cell,
num_encoder_symbols,
num_decoder_symbols,
embedding_size,
num_heads=1,
output_projection=None,
feed_previous=False,
dtype=None,
scope=None,
initial_state_attention=False
)
'''
encoder_inputs = []
decoder_inputs = []
targets_weigh = []
for i in range(input_seq_len):
encoder_inputs.append(tf.placeholder(shape=[None],dtype=tf.int32,name="encoder{0}".format(i)))
for i in range(output_seq_len):
decoder_inputs.append(tf.placeholder(shape=[None],dtype=tf.int32,name="decode{0}".format(i)))
for i in range(output_seq_len):
targets_weigh.append(
tf.placeholder(shape=[None],dtype=tf.float32,name="weight{0}".format(i))
)
targets = [decoder_inputs[i] for i in range(1,output_seq_len)]
targets.append(np.zeros(shape=[2],dtype=np.int32))
cell = tf.nn.rnn_cell.BasicLSTMCell(size)
outputs,_ = seq2seq.embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs,
cell,
num_encoder_symbols=num_encoder_symbols,
num_decoder_symbols=num_decoder_symbols,
embedding_size=size,
output_projection=None,
feed_previous=False,
dtype=tf.float32
)
loss = seq2seq.sequence_loss(
outputs,targets,targets_weigh
)
opt = tf.train.GradientDescentOptimizer(learning_rate=learning_rate)
update = opt.apply_gradients(opt.compute_gradients(loss))
saver = tf.train.Saver(tf.global_variables())
return encoder_inputs,decoder_inputs,targets_weigh,outputs,loss,update,saver
pass
def sequence_loss(self, y_pred, y_true):
'''
Loss function for the seq2seq RNN. Reshape predicted and true (label) tensors, generate dummy weights,
then use seq2seq.sequence_loss to actually compute the loss function.
'''
logits = tf.unstack(
y_pred, axis=1) # list of [-1, num_decoder_synbols] elements
targets = tf.unstack(
y_true, axis=1
) # y_true has shape [-1, self.out_seq_len]; unpack to list of self.out_seq_len [-1] elements
weights = [tf.ones_like(yp, dtype=tf.float32) for yp in targets]
sl = seq2seq.sequence_loss(logits, targets, weights)
return sl
def get_model(feed_previous=False):
"""构造模型
"""
learning_rate = tf.Variable(float(init_learning_rate),
trainable=False,
dtype=tf.float32)
learning_rate_decay_op = learning_rate.assign(learning_rate * 0.99)
encoder_inputs = []
decoder_inputs = []
target_weights = []
for i in range(input_seq_len):
encoder_inputs.append(
tf.placeholder(tf.int32, shape=[None],
name="encoder{0}".format(i)))
for i in range(output_seq_len + 1):
decoder_inputs.append(
tf.placeholder(tf.int32, shape=[None],
name="decoder{0}".format(i)))
for i in range(output_seq_len):
target_weights.append(
tf.placeholder(tf.float32,
shape=[None],
name="weight{0}".format(i)))
# decoder_inputs左移一个时序作为targets
targets = [decoder_inputs[i + 1] for i in range(output_seq_len)]
cell = tf.contrib.rnn.LSTMCell(size)
# 这里输出的状态我们不需要
outputs, _ = seq2seq.embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs[:output_seq_len],
cell,
num_encoder_symbols=num_encoder_symbols,
num_decoder_symbols=num_decoder_symbols,
embedding_size=size,
output_projection=None,
feed_previous=feed_previous,
dtype=tf.float32)
# 计算加权交叉熵损失
loss = seq2seq.sequence_loss(outputs, targets, target_weights)
# 梯度下降优化器
update = tf.train.AdamOptimizer(learning_rate).minimize(loss)
# 模型持久化
saver = tf.train.Saver(tf.global_variables())
return encoder_inputs, decoder_inputs, target_weights, outputs, loss, update, saver, learning_rate_decay_op, learning_rate
def add_loss_op(self, output):
"""将损失添加到目标函数上面
Hint:使用tensorflow.python.ops.seq2seq.sequence_loss 来实现序列损失
参数:
输出:一个张量 大小是 (None,self.vocab)
返回:
损失：一个0-d大小的张量
"""
all_ones = [tf.ones([self.config.batch_size * self.config.num_steps])]
cross_entropy = sequence_loss(
[output], [tf.reshape(self.labels_placeholder, [-1])], all_ones,
len(self.vocab))
tf.add_to_collection('total_loss', cross_entropy)
loss = tf.add_n(tf.get_collection('total_loss'))
return loss
def add_loss_op(self, output):
"""Adds loss ops to the computational graph.
Hint: Use tensorflow.python.ops.seq2seq.sequence_loss to implement sequence loss.
Args:
output: A tensor of shape (None, self.vocab)
Returns:
loss: A 0-d tensor (scalar)
"""
### YOUR CODE HERE
ones = tf.ones([self.config.batch_size * self.config.num_steps])
loss = sequence_loss([output],
[tf.reshape(self.labels_placeholder, [-1])],
[ones])
### END YOUR CODE
return loss
def get_model(feed_previous=False):
"""构造模型
"""
encoder_inputs = []
decoder_inputs = []
target_weights = []
for i in xrange(input_seq_len):
encoder_inputs.append(
tf.placeholder(tf.int32, shape=[None],
name="encoder{0}".format(i)))
for i in xrange(output_seq_len + 1):
decoder_inputs.append(
tf.placeholder(tf.int32, shape=[None],
name="decoder{0}".format(i)))
for i in xrange(output_seq_len):
target_weights.append(
tf.placeholder(tf.float32,
shape=[None],
name="weight{0}".format(i)))
# decoder_inputs左移一个时序作为targets
targets = [decoder_inputs[i + 1] for i in xrange(output_seq_len)]
cell = tf.contrib.rnn.BasicLSTMCell(size)
# 这里输出的状态我们不需要
outputs, _ = seq2seq.embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs[:output_seq_len],
cell,
num_encoder_symbols=num_encoder_symbols,
num_decoder_symbols=num_decoder_symbols,
embedding_size=size,
output_projection=None,
feed_previous=feed_previous,
dtype=tf.float32)
# 计算加权交叉熵损失
loss = seq2seq.sequence_loss(outputs, targets, target_weights)
# 梯度下降优化器
opt = tf.train.GradientDescentOptimizer(learning_rate)
# 优化目标：让loss最小化
update = opt.apply_gradients(opt.compute_gradients(loss))
# 模型持久化
saver = tf.train.Saver(tf.global_variables())
return encoder_inputs, decoder_inputs, target_weights, outputs, loss, update, saver
def add_loss_op(self, output):
"""Adds loss ops to the computational graph.
Hint: Use tensorflow.python.ops.seq2seq.sequence_loss to implement sequence loss.
Args:
output: A tensor of shape (None, self.vocab)
Returns:
loss: A 0-d tensor (scalar)
"""
all_ones = [tf.ones([self.config.batch_size * self.config.num_steps])] # [(640,1)]
targets = [tf.reshape(self.labels_placeholder, [-1])]
cross_entropy = sequence_loss(logits=[output], # [(640,10000)]
targets=targets, # [(640,1)]
weights=all_ones) # [(640,1)]
tf.add_to_collection('total_loss', cross_entropy)
loss = tf.add_n(tf.get_collection('total_loss'))
return loss
def get_model(feed_previous=False):
"""构造模型
"""
learning_rate = tf.Variable(float(init_learning_rate), trainable=False, dtype=tf.float32)
learning_rate_decay_op = learning_rate.assign(learning_rate * 0.9)
encoder_inputs = []
decoder_inputs = []
target_weights = []
for i in xrange(input_seq_len):
encoder_inputs.append(tf.placeholder(tf.int32, shape=[None], name="encoder{0}".format(i)))
for i in xrange(output_seq_len + 1):
decoder_inputs.append(tf.placeholder(tf.int32, shape=[None], name="decoder{0}".format(i)))
for i in xrange(output_seq_len):
target_weights.append(tf.placeholder(tf.float32, shape=[None], name="weight{0}".format(i)))
# decoder_inputs左移一个时序作为targets
targets = [decoder_inputs[i + 1] for i in xrange(output_seq_len)]
cell = tf.contrib.rnn.BasicLSTMCell(size)
# 这里输出的状态我们不需要
outputs, _ = seq2seq.embedding_attention_seq2seq(
encoder_inputs,
decoder_inputs[:output_seq_len],
cell,
num_encoder_symbols=num_encoder_symbols,
num_decoder_symbols=num_decoder_symbols,
embedding_size=size,
output_projection=None,
feed_previous=feed_previous,
dtype=tf.float32)
# 计算加权交叉熵损失
loss = seq2seq.sequence_loss(outputs, targets, target_weights)
# 梯度下降优化器
opt = tf.train.GradientDescentOptimizer(learning_rate)
# 优化目标：让loss最小化
update = opt.apply_gradients(opt.compute_gradients(loss))
# 模型持久化
saver = tf.train.Saver(tf.global_variables())
return encoder_inputs, decoder_inputs, target_weights, outputs, loss, update, saver, learning_rate_decay_op, learning_rate
def add_loss_op(self, output):
"""Adds loss ops to the computational graph.
Hint: Use tensorflow.python.ops.seq2seq.sequence_loss to implement sequence loss.
Args:
output: A tensor of shape (None, self.vocab)
Returns:
loss: A 0-d tensor (scalar)
"""
# YOUR CODE HERE
all_ones = [tf.ones([self.config.batch_size * self.config.num_steps])]
cross_entropy = sequence_loss(
[output], [tf.reshape(self.labels_placeholder, [-1])], all_ones,
len(self.vocab))
tf.add_to_collection('total_loss', cross_entropy)
loss = tf.add_n(tf.get_collection('total_loss'))
# END YOUR CODE
return loss
def sequence_loss(self, y_pred, y_true):
'''
Loss function for the seq2seq RNN. Reshape predicted and true (label) tensors, generate dummy weights,
then use seq2seq.sequence_loss to actually compute the loss function.
'''
if self.verbose > 2:
print("my_sequence_loss y_pred=%s, y_true=%s" % (y_pred, y_true))
logits = tf.unstack(y_pred, axis=1) # list of [-1, num_decoder_synbols] elements
targets = tf.unstack(y_true,
axis=1) # y_true has shape [-1, self.out_seq_len]; unpack to list of self.out_seq_len [-1] elements
if self.verbose > 2:
print("my_sequence_loss logits=%s" % (logits,))
print("my_sequence_loss targets=%s" % (targets,))
weights = [tf.ones_like(yp, dtype=tf.float32) for yp in targets]
if self.verbose > 4:
print("my_sequence_loss weights=%s" % (weights,))
sl = seq2seq.sequence_loss(logits, targets, weights)
if self.verbose > 2:
print("my_sequence_loss return = %s" % sl)
return sl
def sequence_loss(self, y_pred, y_true):
'''
Loss function for the seq2seq RNN. Reshape predicted and true (label) tensors, generate dummy weights,
then use seq2seq.sequence_loss to actually compute the loss function.
'''
if self.verbose > 2:
print("my_sequence_loss y_pred=%s, y_true=%s" % (y_pred, y_true))
logits = tf.unstack(
y_pred, axis=1) # list of [-1, num_decoder_synbols] elements
targets = tf.unstack(
y_true, axis=1
) # y_true has shape [-1, self.out_seq_len]; unstack to list of self.out_seq_len [-1] elements
if self.verbose > 2:
print("my_sequence_loss logits=%s" % (logits, ))
print("my_sequence_loss targets=%s" % (targets, ))
weights = [tf.ones_like(yp, dtype=tf.float32) for yp in targets]
if self.verbose > 4: print("my_sequence_loss weights=%s" % (weights, ))
sl = seq2seq.sequence_loss(logits, targets, weights)
if self.verbose > 2: print("my_sequence_loss return = %s" % sl)
return sl
feed_previous = False,
output_projection = output_projection,
dtype = tf.float32)
# define our loss function
def sampled_loss(labels, logits):
return tf.nn.sampled_softmax_loss(
weights = w_t,
biases = b,
labels = tf.reshape(labels, [-1, 1]),
inputs = logits,
num_sampled = 512,
num_classes = en_vocab_size)
loss = seq2seq_lib.sequence_loss(outputs, targets, target_weights, softmax_loss_function = sampled_loss)
def softmax(x):
n = np.max(x)
e_x = np.exp(x - n)
return e_x / e_x.sum()
# feed data into placeholders
def feed_dict(x, y, batch_size = 64):
feed = {}
idxes = np.random.choice(len(x), size = batch_size, replace = False)
for i in range(input_seq_len):
feed[encoder_inputs[i].name] = np.array([x[j][i] for j in idxes])
def rnn_model(model, input_data, output_data,labels, vocab_size, batch_size=64,rnn_size=128):
"""
construct rnn seq2seq model.
:param model: model class
:param input_data: input data placeholder
:param output_data: output data placeholder
:param vocab_size:
:param rnn_size:
:param num_layers:
:param batch_size:
:param learning_rate:
:return:
"""
end_points = {}
if model == 'rnn':
cell_fun = tf.contrib.rnn.BasicRNNCell
elif model == 'gru':
cell_fun = tf.contrib.rnn.GRUCell
elif model == 'lstm':
cell_fun = tf.contrib.rnn.BasicLSTMCell
cell = cell_fun(rnn_size)
# cell = tf.contrib.rnn.MultiRNNCell([cell] * num_layers, state_is_tuple=True)
weights = [tf.ones_like(labels_t, dtype=tf.float32) for labels_t in labels]
outputs,last_state = seq2seq.embedding_rnn_seq2seq(input_data,output_data,cell,vocab_size,vocab_size,len(input_data))
loss = seq2seq.sequence_loss(ou, labels, weights, vocab_size)
tf.scalar_summary("loss", loss)
magnitude = tf.sqrt(tf.reduce_sum(tf.square(last_state[1])))
tf.scalar_summary("magnitude at t=1", magnitude)
summary_op = tf.merge_all_summaries()
learning_rate = 0.05
momentum = 0.9
optimizer = tf.train.MomentumOptimizer(learning_rate, momentum)
train_op = optimizer.minimize(loss)
logdir = tempfile.mkdtemp()
print(logdir)
summary_writer = tf.train.SummaryWriter(logdir, sess.graph_def)
# if output_data is not None:
# initial_state = cell.zero_state(batch_size, tf.float32)
# else:
# initial_state = cell.zero_state(1, tf.float32)
# with tf.device("/cpu:0"):
# embedding = tf.get_variable('embedding', initializer=tf.random_uniform(
# [vocab_size + 1, rnn_size], -1.0, 1.0))
# inputs = tf.nn.embedding_lookup(embedding, input_data)
# decoder_inputs = tf.nn.embedding_lookup(embedding, output_data)
# # [batch_size, ?, rnn_size] = [64, ?, 128]
# # outputs, last_state = tf.nn.dynamic_rnn(cell, inputs, initial_state=initial_state)
# outputs,last_state = basic_rnn_seq2seq(inputs,decoder_inputs,cell)
# output = tf.reshape(outputs, [-1, rnn_size])
# weights = tf.Variable(tf.truncated_normal([rnn_size, vocab_size + 1]))
# bias = tf.Variable(tf.zeros(shape=[vocab_size + 1]))
# logits = tf.nn.bias_add(tf.matmul(output, weights), bias=bias)
# # [?, vocab_size+1]
# if output_data is not None:
# # output_data must be one-hot encode
# labels = tf.one_hot(tf.reshape(output_data, [-1]), depth=vocab_size + 1)
# # should be [?, vocab_size+1]
# loss = tf.nn.softmax_cross_entropy_with_logits(labels=labels, logits=logits)
# # loss shape should be [?, vocab_size+1]
# total_loss = tf.reduce_mean(loss)
# train_op = tf.train.AdamOptimizer(learning_rate).minimize(total_loss)
# end_points['initial_state'] = initial_state
# end_points['output'] = output
# end_points['train_op'] = train_op
# end_points['total_loss'] = total_loss
# end_points['loss'] = loss
# end_points['last_state'] = last_state
# else:
# prediction = tf.nn.softmax(logits)
# end_points['initial_state'] = initial_state
# end_points['last_state'] = last_state
# end_points['prediction'] = prediction
# return end_points
def create_model(self,
model_input,
vocab_size,
num_frames,
is_training=True,
sparse_labels=None,
label_weights=None,
**unused_params):
self.phase_train = is_training
num_frames = tf.cast(tf.expand_dims(num_frames, 1), tf.float32)
model_inputs = utils.SampleRandomSequence(model_input, num_frames,
self.max_steps)
total_vocab_size = vocab_size + 3
enc_cell = self.get_enc_cell(self.cell_size, total_vocab_size)
dec_cell = self.get_dec_cell(self.cell_size)
runtime_batch_size = tf.shape(model_inputs)[0]
# TODO
if False:
with tf.variable_scope("Enc"):
enc_init_state = enc_cell.zero_state(runtime_batch_size,
dtype=tf.float32)
enc_outputs, enc_state = tf.nn.dynamic_rnn(
enc_cell,
model_inputs,
initial_state=enc_init_state,
scope="enc")
else:
enc_outputs = model_inputs
enc_state = dec_cell.zero_state(runtime_batch_size,
dtype=tf.float32)
label_weights = tf.cast(label_weights, tf.float32)
dec_weights = tf.unstack(label_weights, axis=1)
dec_input_lists = tf.unstack(sparse_labels, axis=1)
dec_targets = [
dec_input_lists[i + 1] for i in xrange(len(dec_input_lists) - 1)
]
dec_targets += [tf.zeros_like(dec_input_lists[0])]
# enc_outputs_lists = tf.split(enc_outputs, num_or_size_splits=self.max_steps, axis=1)
dec_outputs, _ = attn.embedding_attention_decoder(
dec_input_lists,
initial_state=enc_state,
attention_states=enc_outputs,
cell=dec_cell,
num_symbols=total_vocab_size,
embedding_size=1024,
output_size=total_vocab_size,
output_projection=None,
feed_previous=False,
dtype=tf.float32,
scope="LSTMEncDec")
loss = seq2seq_lib.sequence_loss(dec_outputs,
dec_targets,
dec_weights,
softmax_loss_function=None)
# logits = tf.reduce_mean(dec_outputs, axis=0)
label_num = tf.reduce_sum(label_weights, axis=1, keep_dims=True)
logits = tf.add_n(dec_outputs) / label_num
# logits = tf.Print(logits.get_shape(), [logits])
logits = logits[:, :vocab_size]
# logits = tf.nn.sigmoid(enc_outputs[:, -1, :])
return {
"predictions": dec_outputs,
# "predictions": logits,
"loss": loss,
}
def _seq2seq(self):
hps = self._hps
vocab_size = self._vocab.count
with tf.variable_scope("SumModel"):
article_lens = self._article_lens
# 由于sequence loss需要 seq_len * [batch_size]
targets = tf.unstack(tf.transpose(self._targets))
loss_weights = tf.unstack(tf.transpose(self._loss_weights))
with tf.variable_scope('embedding'), tf.device('/cpu:0'):
embedding = tf.get_variable("embedding",
[vocab_size, hps.emb_dim],
dtype=tf.float32)
# [batch, seq_len, emb_dim]
emb_encoder_inputs = tf.nn.embedding_lookup(
embedding, self._articles)
emb_decoder_inputs = tf.nn.embedding_lookup(
embedding, self._abstracts)
with tf.variable_scope("encoder"):
cell_fw = LSTMCell(hps.num_hidden,
initializer=tf.random_uniform_initializer(
-0.1, 0.1, seed=123),
state_is_tuple=False)
cell_bw = LSTMCell(hps.num_hidden,
initializer=tf.random_uniform_initializer(
-0.1, 0.1, seed=113),
state_is_tuple=False)
# outputs: (output_fw, output_bw) => output_fw: [batch_size, max_time, cell_fw.output_size]
# output_states: A tuple (output_state_fw, output_state_bw)
encoder_outputs, encoder_output_states = tf.nn.bidirectional_dynamic_rnn(
cell_fw,
cell_bw,
inputs=emb_encoder_inputs,
dtype=tf.float32,
sequence_length=article_lens)
# encoder_outputs: [batch_size, max_time, 2 * output_size]
self._enc_outputs = tf.concat(encoder_outputs, axis=2)
# [batch_size, 2 * output_size]
encoder_state_fw, _ = encoder_output_states
with tf.variable_scope("output_projection"):
w = tf.get_variable(
"w", [hps.num_hidden, vocab_size],
dtype=tf.float32,
initializer=tf.truncated_normal_initializer(stddev=1e-4))
v = tf.get_variable(
"b", [vocab_size],
dtype=tf.float32,
initializer=tf.truncated_normal_initializer(stddev=1e-4))
with tf.variable_scope("decoder"):
loop_function = None
if hps.mode == "test":
loop_function = _extract_argmax_and_embed(
embedding, (w, v), update_embedding=False)
decoder_cell = LSTMCell(
hps.num_hidden,
initializer=tf.random_uniform_initializer(-0.1,
0.1,
seed=113),
state_is_tuple=False)
# 将实际输入转化成符合要求的输入
# [seq_len, batch, emb_dim] => seq_len * [batch, emb_dim]
emb_decoder_inputs = tf.unstack(
tf.transpose(emb_decoder_inputs, perm=[1, 0, 2]))
# [batch, cell_size]
self._dec_in_state = encoder_state_fw
initial_state_attention = (hps.mode == 'test')
# decoder_outputs: seq_len * [batch, hidden_size]
# self._dec_out_state: [batch, state_size]=[batch, 2*cell_size]
decoder_outputs, self._dec_out_state = attention_decoder(
decoder_inputs=emb_decoder_inputs,
initial_state=self._dec_in_state,
attention_states=self._enc_outputs,
cell=decoder_cell,
num_heads=1,
loop_function=loop_function,
initial_state_attention=initial_state_attention)
with tf.variable_scope("output"):
# 还可以写成
#[batch * seq_len, vsize]
output = tf.reshape(tf.stack(values=decoder_outputs, axis=1),
[-1, hps.num_hidden])
logits = tf.matmul(output, w) + v
model_outputs = tf.unstack(tf.reshape(
logits, [-1, hps.dec_timesteps, vocab_size]),
axis=1)
# seq_len * [batch, vsize]
# 输出层共享
# model_outputs = []
# for i in range(len(decoder_outputs)):
# if i > 0:
# tf.get_variable_scope().reuse_variables()
# model_outputs.append(
# tf.nn.xw_plus_b(decoder_outputs[i], w, v))
with tf.variable_scope("loss"):
# logits: seq_len * [batch_size, vsize]
# targets: seq_len * [batch_size]
# weights: seq_len * [batch_size] 注意这里的weights的作用是做mask
# 1. sequence_loss先是调用sequence_loss_by_example,获取[batch_size]维的loss，在除以batch_size
# 2. sequence_loss_by_example利用weights来做mask，获取实际的每个time_step的平均loss
# 因为batch里面实际句子长度不一样，所有weights要先初始化zeros,然后向里面填1
self._loss = sequence_loss(logits=model_outputs,
targets=targets,
weights=loss_weights)
if hps.mode == "test":
with tf.variable_scope("decode_output"):
# seq_len * [batch, vsize] => seq_len * [batch, 1]
best_outputs = [tf.arg_max(x, 1) for x in model_outputs]
# [batch, seq_len]
self._outputs = tf.concat(
axis=1,
values=[tf.reshape(x, [-1, 1]) for x in best_outputs])
def create_model(self,
model_input,
vocab_size,
num_frames,
is_training=True,
dense_labels=None,
feature_sizes=None,
input_weights=None,
**unused_params):
self.is_training = is_training
feature_size = sum(feature_sizes)
num_frames = tf.cast(tf.expand_dims(num_frames, 1), tf.float32)
# TODO
self.max_steps = 300 # 30
enc_inputs = utils.SampleRandomSequence(model_input, num_frames,
self.max_steps)
enc_cell = self.get_enc_cell(self.cell_size, self.cell_size)
dec_cell = self.get_dec_cell(self.cell_size)
runtime_batch_size = tf.shape(enc_inputs)[0]
enc_init_state = enc_cell.zero_state(runtime_batch_size,
dtype=tf.float32)
enc_outputs, enc_state = tf.nn.dynamic_rnn(
enc_cell, enc_inputs, initial_state=enc_init_state, scope="enc")
if True:
enc_outputs_stopped = tf.stop_gradient(enc_outputs)
input_weights = tf.tile(tf.expand_dims(input_weights, 2),
[1, 1, self.cell_size])
enc_outputs_stopped = enc_outputs_stopped * input_weights
enc_rep = tf.reduce_sum(enc_outputs_stopped, axis=1) / num_frames
# enc_rep = tf.reduce_sum(enc_outputs_stopped, axis=1) / self.max_steps
self.vocab_size = vocab_size
cls_func = self.moe
logits = cls_func(enc_rep)
if cls_func == self.moe:
epsilon = 1e-12
labels = tf.cast(dense_labels, tf.float32)
cross_entropy_loss = labels * tf.log(logits + epsilon) + (
1 - labels) * tf.log(1 - logits + epsilon)
cross_entropy_loss = tf.negative(cross_entropy_loss)
loss = tf.reduce_mean(tf.reduce_sum(cross_entropy_loss, 1))
predictions = logits
else:
loss = tf.nn.sigmoid_cross_entropy_with_logits(labels=tf.cast(
dense_labels, tf.float32),
logits=logits)
loss = tf.reduce_mean(tf.reduce_sum(loss, 1))
predictions = tf.nn.sigmoid(logits)
else:
dec_targets = tf.unstack(enc_inputs, axis=1)
dec_targets.reverse()
dec_inputs = [tf.zeros_like(dec_targets[0])] + dec_targets[:-1]
dec_outputs, _ = attn.attention_decoder(
decoder_inputs=dec_inputs,
initial_state=enc_state,
attention_states=enc_outputs,
cell=dec_cell,
output_size=feature_size,
dtype=tf.float32)
dec_weights = []
for _ in xrange(self.max_steps):
dec_weights.append(
tf.ones([
runtime_batch_size,
], dtype=tf.float32))
loss = seq2seq_lib.sequence_loss(
dec_outputs,
dec_targets,
dec_weights,
softmax_loss_function=self.reconstruct_loss)
predictions = tf.no_op()
return {
"loss": loss,
"predictions": predictions,
}
def _build_model(self):
"""
Builds a model either for training or testing
:return:
"""
cell = self._set_cell_type()
self._build_inputs()
output_projection = None
print("Embedding size: ", self.embedding_size)
if self.use_attn:
if self.copy:
print("Using attention of form ", self.attn_type,
" with copy mechanism...")
else:
print("Using attention of form ", self.attn_type)
self.outputs, self.states, self.attn_outputs = embedding_attention_seq2seq(
self.encoder_inputs,
self.decoder_inputs,
cell,
num_encoder_symbols=self.vocab_size,
num_decoder_symbols=self.vocab_size,
embedding_size=self.embedding_size,
output_projection=output_projection,
feed_previous=self.do_decode,
dtype=tf.float32,
copy=self.copy,
attn_type=self.attn_type)
else:
print("Using vanilla seq2seq...")
self.outputs, self.states = embedding_rnn_seq2seq(
self.encoder_inputs,
self.decoder_inputs,
cell,
num_encoder_symbols=self.vocab_size,
num_decoder_symbols=self.vocab_size,
embedding_size=self.embedding_size,
output_projection=output_projection,
feed_previous=self.do_decode,
dtype=tf.float32)
self.attn_outputs = None
# Compute loss -- averaged across batch + with l2 loss added
trainable_vars = tf.get_collection(tf.GraphKeys.TRAINABLE_VARIABLES)
# Only get non-bias terms
non_bias_vars = [v for v in trainable_vars if "Bias" not in v.name]
l2_loss = tf.add_n(
[self.l2_reg * tf.nn.l2_loss(nb) for nb in non_bias_vars])
# Compute loss -- averaged across batch
self.total_loss = sequence_loss(self.outputs, self.decoder_inputs,
self.target_weights) + l2_loss
self.training_op = tf.train.AdamOptimizer(
learning_rate=0.0001).minimize(self.total_loss)
self.dec_prediction = tf.transpose(tf.argmax(self.outputs, axis=1),
[1, 0])
self.predictions = tf.transpose(
tf.argmax(tf.stack(self.outputs), axis=-1), [1, 0])
self.saver = tf.train.Saver(max_to_keep=10)
self.increment_global_step = tf.assign_add(
self.global_step, 1, name='increment_global_step')