def __init__(self,
config_path,
checkpoint_path,
hidden_size,
num_classes,
ls_e=0.1,
model_type='bert'):
def ls_loss(y_true, y_pred, e=ls_e):
loss1 = K.categorical_crossentropy(y_true, y_pred)
loss2 = K.categorical_crossentropy(
K.ones_like(y_pred) / num_classes, y_pred)
return (1 - e) * loss1 + e * loss2
self.num_classes = num_classes
bert = build_transformer_model(config_path=config_path,
checkpoint_path=checkpoint_path,
model=model_type,
return_keras_model=False)
text_emb = Lambda(lambda x: x[:, 0],
name='CLS-token')(bert.model.output)
text_emb = Dense(hidden_size, activation='tanh')(text_emb)
output = Dense(num_classes, activation='softmax')(text_emb)
self.model = Model(bert.model.input, output)
AdamLR = extend_with_piecewise_linear_lr(Adam, name='AdamLR')
self.model.compile(loss=ls_loss,
optimizer=AdamLR(learning_rate=1e-4,
lr_schedule={
1000: 1,
2000: 0.1
}))
def taggerRewriterModel(model_name,
config_path,
checkpoint_path,
num_classes=5,
learning_rate=3e-5):
# 补充输入
start_labels = Input(shape=(1, ), name='Start-Labels')
end_labels = Input(shape=(1, ), name='End-Lables')
insert_pos_labels = Input(shape=(1, ), name='Insert-Pos-Labels')
start_ner_labels = Input(shape=(1, ), name='Start-NER-Labels')
end_ner_labels = Input(shape=(1, ), name='End-NER-Labels')
# 加载预训练模型
bert = build_transformer_model(
config_path=config_path,
checkpoint_path=checkpoint_path,
model='albert',
return_keras_model=False,
)
output = bert.model.output
output = Dense(units=num_classes,
activation='linear',
kernel_initializer=bert.initializer)(output)
start_pred = Lambda(lambda x: x[:, :, 0], name='start')(output)
end_pred = Lambda(lambda x: x[:, :, 1], name='end')(output)
insert_pos_pred = Lambda(lambda x: x[:, :, 2], name='insrt_pos')(output)
start_ner_pred = Lambda(lambda x: x[:, :, 3], name='start_ner')(output)
end_ner_pred = Lambda(lambda x: x[:, :, 4], name='end_ner')(output)
start_pred, end_pred, insert_pos_pred, start_ner_pred, end_ner_pred = PointerLoss(
[5, 6, 7, 8, 9])([
start_labels, end_labels, insert_pos_labels, start_ner_labels,
end_ner_labels, start_pred, end_pred, insert_pos_pred,
start_ner_pred, end_ner_pred
])
model = keras.models.Model(
bert.model.inputs + [
start_labels, end_labels, insert_pos_labels, start_ner_labels,
end_ner_labels
],
[start_pred, end_pred, insert_pos_pred, start_ner_pred, end_ner_pred])
model.summary()
# 派生为带分段线性学习率的优化器。
# 其中name参数可选，但最好填入，以区分不同的派生优化器。
AdamLR = extend_with_piecewise_linear_lr(Adam)
model.compile(
# optimizer=Adam(1e-5), # 用足够小的学习率
optimizer=AdamLR(learning_rate=learning_rate,
lr_schedule={
1000: 1,
2000: 0.1
}),
metrics=None,
)
return model
def fit(self, train_filepath, valid_filepath, temp_save_path,
maxlen=128, learning_rate=1e-4, epochs=5, batch_size=32):
train_data = load_data(train_filepath)
train_generator = CmtDataGenerator(train_data, batch_size, self.tokenizer)
callbacks = None
if valid_filepath != "" and valid_filepath is not None \
and temp_save_path != "" and temp_save_path is not None:
valid_data = load_data(valid_filepath)
valid_generator = CmtDataGenerator(valid_data, batch_size, self.tokenizer)
evaluator = Evaluator(self.model, valid_generator, temp_save_path)
callbacks = [evaluator]
AdamLR = extend_with_piecewise_linear_lr(Adam, name='AdamLR')
self.model.compile(
loss='sparse_categorical_crossentropy',
optimizer=AdamLR(learning_rate=learning_rate, lr_schedule={
1000: 1,
2000: 0.1
}),
metrics=['accuracy'],
)
self.model.fit(
train_generator.forfit(),
steps_per_epoch=len(train_generator),
epochs=epochs,
callbacks=callbacks
)
if callbacks is not None:
self.model.load_weights(temp_save_path)
def build_transformer_model_for_pretraining():
"""构建训练模型，通用于TPU/GPU
注意全程要用keras标准的层写法，一些比较灵活的“移花接木”式的
写法可能会在TPU上训练失败。此外，要注意的是TPU并非支持所有
tensorflow算子，尤其不支持动态（变长）算子，因此编写相应运算
时要格外留意。
"""
bert, train_model, loss = build_transformer_model_with_mlm()
# 优化器
optimizer = extend_with_weight_decay(Adam)
if which_optimizer == 'lamb':
optimizer = extend_with_layer_adaptation(optimizer)
optimizer = extend_with_piecewise_linear_lr(optimizer)
optimizer_params = {
'learning_rate': learning_rate,
'lr_schedule': lr_schedule,
'weight_decay_rate': weight_decay_rate,
'exclude_from_weight_decay': exclude_from_weight_decay,
'bias_correction': False,
}
if grad_accum_steps > 1:
optimizer = extend_with_gradient_accumulation(optimizer)
optimizer_params['grad_accum_steps'] = grad_accum_steps
optimizer = optimizer(**optimizer_params)
# 模型定型
train_model.compile(loss=loss, optimizer=optimizer)
# 如果传入权重，则加载。注：须在此处加载，才保证不报错。
if checkpoint_path is not None:
bert.load_weights_from_checkpoint(checkpoint_path)
return train_model
def build(self):
bert_model, _ = load_bert(
config_path=os.path.join(self.config['pretrained_model_dir'],
'bert_config.json'),
checkpoint_path=os.path.join(self.config['pretrained_model_dir'],
'bert_model.ckpt'),
)
text_mask = L.Lambda(
lambda x: K.cast(K.expand_dims(K.greater(x, 0), 2), K.floatx()))(
bert_model.input[0])
# GI
gi_in = L.Input(name="gi",
shape=(self.config["max_len"], ),
dtype="float32")
gi = gi_in
# AGN
X = bert_model.output
gi = L.Dense(self.config['max_len'], activation='tanh')(gi) # (B, L)
gi = L.Lambda(lambda x: K.expand_dims(x, 2))(gi) # (B, L, 1)
X, attn_weight = AGN(epsilon=self.config['epsilon'])([X, gi])
X = L.Lambda(lambda x: x[0] - 1e10 * (1.0 - x[1]))([X, text_mask])
output = L.Lambda(lambda x: K.max(x, 1))(X)
#output = L.Dense(128, activation='relu')(output)
output = L.Dropout(self.config.get('dropout', 0.2))(output)
output = L.Dense(self.config['output_size'],
activation='softmax')(output)
self.model = keras.Model(inputs=(*bert_model.input, gi_in),
outputs=output)
self.attn_model = keras.Model(inputs=(*bert_model.input, gi_in),
outputs=attn_weight)
optimizer = extend_with_weight_decay(Adam)
optimizer = extend_with_piecewise_linear_lr(optimizer)
optimizer_params = {
'learning_rate': self.config['learning_rate'],
'lr_schedule': {
self.config['steps_per_epoch'] * 2: 1,
self.config['steps_per_epoch'] * 3: 0.2,
self.config['steps_per_epoch'] * self.config['epochs']: 0.1
},
'weight_decay_rate': 0.01,
'exclude_from_weight_decay': ['Norm', 'bias'],
'bias_correction': False,
}
self.model.compile(
loss='sparse_categorical_crossentropy',
optimizer=optimizer(**optimizer_params),
)
self.model.summary()
if self.config.get('apply_fgm', True):
print('apply fgm')
fgm(self.model, 'Embedding-Token',
self.config.get('fgm_epsilon', 0.2))
def compile_model(self):
# 派生为带分段线性学习率的优化器。
# 其中name参数可选，但最好填入，以区分不同的派生优化器。
AdamLR = extend_with_piecewise_linear_lr(Adam, name='AdamLR')
self.model.compile(loss=self.loss,
optimizer=AdamLR(lr=self.learning_rate, lr_schedule={
1000: 1,
2000: 0.1
}),
metrics=self.metrics, )
def get_suggested_optimizer(init_lr=5e-5, total_steps=None):
lr_schedule = {1000: 1, 10000: 0.01}
if total_steps is not None:
lr_schedule = {total_steps // 10: 1, total_steps: 0.1}
optimizer = extend_with_weight_decay(Adam)
optimizer = extend_with_piecewise_linear_lr(optimizer)
optimizer_params = {
'learning_rate': init_lr,
'lr_schedule': lr_schedule,
'weight_decay_rate': 0.01,
'exclude_from_weight_decay': ['Norm', 'bias'],
'bias_correction': False,
}
optimizer = optimizer(**optimizer_params)
return optimizer
def get_optimizer_cls(self, optimizer_cls):
optimizer_list = [
"Adam",
"Adamax",
"Adagrad",
"Nadam",
"Adadelta",
"SGD",
"RMSprop",
]
if isinstance(optimizer_cls, str):
if optimizer_cls and optimizer_cls in optimizer_list:
optimizer_cls = getattr(tf.keras.optimizers, optimizer_cls)
if not issubclass(optimizer_cls, tf.keras.optimizers.Optimizer):
raise Exception(f"指定的 Optimizer 类别不正确！{optimizer_cls}")
if self.optimize_with_piecewise_linear_lr:
optimizer_cls = extend_with_piecewise_linear_lr(optimizer_cls)
return optimizer_cls
def __init_model(self, config_path, checkpoint_path):
bert = build_transformer_model(config_path=config_path,
checkpoint_path=checkpoint_path,
model='electra',
return_keras_model=False)
output = Lambda(lambda x: x[:, 0], name='CLS-token')(bert.model.output)
output = Dense(units=self.num_classes,
activation='softmax',
kernel_initializer=bert.initializer)(output)
AdamLR = extend_with_piecewise_linear_lr(Adam)
model = keras.models.Model(bert.model.input, output)
model.compile(
loss='sparse_categorical_crossentropy',
optimizer=AdamLR(learning_rate=1e-3,
lr_schedule={
1000: 1,
2000: 0.1
}),
metrics=['accuracy'],
)
return model
bert = build_bert_model(
config_path=config_path,
checkpoint_path=checkpoint_path,
with_pool=True,
albert=True,
return_keras_model=False,
)
output = Dropout(rate=0.1)(bert.model.output)
output = Dense(units=2,
activation='softmax',
kernel_initializer=bert.initializer)(output)
model = keras.models.Model(bert.model.input, output)
model.summary()
AdamLR = extend_with_piecewise_linear_lr(Adam)
model.compile(
loss='sparse_categorical_crossentropy',
optimizer=AdamLR(learning_rate=1e-4, lr_schedule={
1000: 1,
2000: 0.1
}),
metrics=['accuracy'],
)
# 转换数据集
train_generator = data_generator(train_data)
valid_generator = data_generator(valid_data)
test_generator = data_generator(test_data)
elif config.lstm:
output = Bidirectional(LSTM(256))(output)
else:
pass
# output =GlobalAvgPool1D()(output) #平均池化
output = Dropout(0.15)(output)
output = Dense(units=num_classes,
activation='softmax',
kernel_initializer=bert.initializer)(output)
model = keras.models.Model(bert.model.input, output)
model.summary()
# 派生为带分段线性学习率的优化器。
# 其中name参数可选，但最好填入，以区分不同的派生优化器。
AdamLR = extend_with_piecewise_linear_lr(Adam, name='AdamLR')
if config.addadv:
"""添加扰动"""
loss = loss_with_gradient_penalty()
else:
loss = 'categorical_crossentropy'
model.compile(
loss='categorical_crossentropy',
optimizer=Adam(1e-5), # 用足够小的学习率
# optimizer=AdamLR(learning_rate=1e-4, lr_schedule={
# 1000: 1,
# 2000: 0.1
# }),
# metrics=['accuracy'],
def build_train_bert_model():
"""构建训练模型，通用于TPU/GPU
注意全程要用keras标准的层写法，一些比较灵活的“移花接木”式的
写法可能会在TPU上训练失败。此外，要注意的是TPU并非支持所有
tensorflow算子，尤其不支持动态（变长）算子，因此编写相应运算
时要格外留意。
"""
bert = build_bert_model(config_path,
with_mlm='linear',
application='lm',
return_keras_model=False)
token_ids = bert.model.input[0]
proba = bert.model.output
def lm_loss(inputs):
"""计算loss的函数，需要封装为一个层
"""
y_true, y_pred, mask = inputs
y_true = y_true[:, 1:]
y_pred = y_pred[:, :-1]
mask = mask[:, 1:]
loss = K.sparse_categorical_crossentropy(y_true,
y_pred,
from_logits=True)
loss = K.sum(loss * mask) / (K.sum(mask) + K.epsilon())
return loss
def lm_acc(inputs):
"""计算准确率的函数，需要封装为一个层
"""
y_true, y_pred, mask = inputs
y_true = K.cast(y_true, K.floatx())
y_true = y_true[:, 1:]
y_pred = y_pred[:, :-1]
mask = mask[:, 1:]
acc = keras.metrics.sparse_categorical_accuracy(y_true, y_pred)
acc = K.sum(acc * mask) / (K.sum(mask) + K.epsilon())
return acc
mask = bert.model.get_layer('Sequence-Mask').output
loss = Lambda(lm_loss, name='lm_loss')([token_ids, proba, mask])
acc = Lambda(lm_acc, name='lm_acc')([token_ids, proba, mask])
train_model = Model(bert.model.inputs, [loss, acc])
# 优化器
optimizer = extend_with_weight_decay(Adam)
if which_optimizer == 'lamb':
optimizer = extend_with_layer_adaptation(optimizer)
optimizer = extend_with_piecewise_linear_lr(optimizer)
optimizer_params = {
'learning_rate': learning_rate,
'lr_schedule': lr_schedule,
'weight_decay_rate': weight_decay_rate,
'exclude_from_weight_decay': exclude_from_weight_decay,
'bias_correction': False,
}
if grad_accum_steps > 1:
optimizer = extend_with_gradient_accumulation(optimizer)
optimizer_params['grad_accum_steps'] = grad_accum_steps
optimizer = optimizer(**optimizer_params)
# 模型定型
train_model.compile(
loss={
'lm_loss': lambda y_true, y_pred: y_pred,
'lm_acc': lambda y_true, y_pred: K.stop_gradient(y_pred),
},
optimizer=optimizer,
)
# 如果传入权重，则加载。注：须在此处加载，才保证不报错。
if checkpoint_path is not None:
bert.load_weights_from_checkpoint(checkpoint_path)
return train_model
def build_train_bert_model():
"""构建训练模型，通用于TPU/GPU
注意全程要用keras标准的层写法，一些比较灵活的“移花接木”式的
写法可能会在TPU上训练失败。此外，要注意的是TPU并非支持所有
tensorflow算子，尤其不支持动态（变长）算子，因此编写相应运算
时要格外留意。
"""
bert = build_bert_model(config_path, with_mlm='linear', return_keras_model=False)
bert_model = bert.model
proba = bert_model.output
# 辅助输入
token_ids = Input(shape=(None, ), dtype='int64', name='token_ids') # 目标id
is_masked = Input(shape=(None, ), dtype='bool', name='is_masked') # mask标记
def mlm_loss(inputs):
"""计算loss的函数，需要封装为一个层
"""
y_true, y_pred, is_masked = inputs
is_masked = K.cast(is_masked, K.floatx())
loss = K.sparse_categorical_crossentropy(y_true, y_pred, from_logits=True)
loss = K.sum(loss * is_masked) / (K.sum(is_masked) + K.epsilon())
return loss
def mlm_acc(inputs):
"""计算准确率的函数，需要封装为一个层
"""
y_true, y_pred, is_masked = inputs
is_masked = K.cast(is_masked, K.floatx())
y_true = K.cast(y_true, K.floatx())
acc = keras.metrics.sparse_categorical_accuracy(y_true, y_pred)
acc = K.sum(acc * is_masked) / (K.sum(is_masked) + K.epsilon())
return acc
loss = Lambda(mlm_loss, name='mlm_loss')([token_ids, proba, is_masked])
acc = Lambda(mlm_acc, name='mlm_acc')([token_ids, proba, is_masked])
train_model = Model(bert_model.inputs + [token_ids, is_masked], [loss, acc])
# 优化器
optimizer = extend_with_weight_decay(Adam)
if which_optimizer == 'lamb':
optimizer = extend_with_layer_adaptation(optimizer)
optimizer = extend_with_piecewise_linear_lr(optimizer)
optimizer_params = {
'learning_rate': learning_rate,
'lr_schedule': lr_schedule,
'weight_decay_rate': weight_decay_rate,
'exclude_from_weight_decay': exclude_from_weight_decay,
'bias_correction': False,
}
if grad_accum_steps > 1:
optimizer = extend_with_gradient_accumulation(optimizer)
optimizer_params['grad_accum_steps'] = grad_accum_steps
optimizer = optimizer(**optimizer_params)
# 模型定型
train_model.compile(
loss={
'mlm_loss': lambda y_true, y_pred: y_pred,
'mlm_acc': lambda y_true, y_pred: K.stop_gradient(y_pred),
},
optimizer=optimizer,
)
# 如果传入权重，则加载。注：须在此处加载，才保证不报错。
if checkpoint_path is not None:
bert.load_weights_from_checkpoint(checkpoint_path)
return train_model
def optimizer(self):
AdamLR = extend_with_piecewise_linear_lr(Adam, name='AdamLR')
_optimizer = AdamLR(lr=1e-5, lr_schedule={1000: 1, 2000: 0.1})
return _optimizer
Author : chenhao
date： 2021/3/30
-------------------------------------------------
Change Activity:
2021/3/30:
-------------------------------------------------
"""
from tensorflow.keras.optimizers import (Adadelta, Adagrad, Adamax, Nadam,
RMSprop, SGD, Adam)
from bert4keras.optimizers import extend_with_exponential_moving_average, extend_with_piecewise_linear_lr, \
extend_with_gradient_accumulation
AdamEMA = extend_with_exponential_moving_average(Adam, name='AdamEMA')
# 变成带分段线性学习率的Adam
AdamLR = extend_with_piecewise_linear_lr(Adam, 'AdamLR')
# 梯度累积的Adam
AdamAcc = extend_with_gradient_accumulation(Adam, 'AdamAcc')
# 梯度累积的分段线性学习率Adam
AdamAccLR = extend_with_piecewise_linear_lr(AdamAcc, 'AdamAccLR')
class OptimizerFactory:
_BUILDERS = {
'sgd': SGD,
'rmsprop': RMSprop,
'adagrad': Adagrad,
'adadelta': Adadelta,
'adam': Adam,
'adamax': Adamax,
'nadam': Nadam,
def __init__(self,
config_path,
checkpoint_path,
hidden_size,
num_classes,
alpha,
wvdim=768,
model_type='bert',
label_embedding_matrix=None):
self.num_classes = num_classes
def lcm_loss(y_true, y_pred, alpha=alpha):
pred_porbs = y_pred[:, :num_classes]
label_sim_dist = y_pred[:, num_classes:]
simulated_y_true = K.softmax(label_sim_dist + alpha * y_true)
loss1 = -K.categorical_crossentropy(simulated_y_true,
simulated_y_true)
loss2 = K.categorical_crossentropy(simulated_y_true, pred_probs)
return loss1 + loss2
def ls_loss(y_true, y_pred, e=0.1):
loss1 = K.categorical_crossentropy(y_true, y_pred)
loss2 = K.categorical_crossentropy(
K.ones_like(y_pred) / num_classes, y_pred)
return (1 - e) * loss1 + e * loss2
# text_encoder:
bert = build_transformer_model(config_path=config_path,
checkpoint_path=checkpoint_path,
model=model_type,
return_keras_model=False)
text_emb = Lambda(lambda x: x[:, 0],
name='CLS-token')(bert.model.output)
text_emb = Dense(hidden_size, activation='tanh')(text_emb)
pred_probs = Dense(num_classes, activation='softmax')(text_emb)
self.basic_predictor = Model(bert.model.input, pred_probs)
AdamLR = extend_with_piecewise_linear_lr(Adam, name='AdamLR')
self.basic_predictor.compile(loss='categorical_crossentropy',
optimizer=AdamLR(learning_rate=1e-4,
lr_schedule={
1000: 1,
2000: 0.1
}))
# label_encoder:
label_input = Input(shape=(num_classes, ), name='label_input')
if label_embedding_matrix is None: # 不使用pretrained embedding
label_emb = Embedding(num_classes,
wvdim,
input_length=num_classes,
name='label_emb1')(label_input) # (n,wvdim)
else:
label_emb = Embedding(num_classes,
wvdim,
input_length=num_classes,
weights=[label_embedding_matrix],
name='label_emb1')(label_input)
# label_emb = Bidirectional(LSTM(hidden_size,return_sequences=True),merge_mode='ave')(label_emb) # (n,d)
label_emb = Dense(hidden_size, activation='tanh',
name='label_emb2')(label_emb)
# similarity part:
doc_product = Dot(axes=(2, 1))([label_emb,
text_emb]) # (n,d) dot (d,1) --> (n,1)
label_sim_dict = Dense(num_classes,
activation='softmax',
name='label_sim_dict')(doc_product)
# concat output:
concat_output = Concatenate()([pred_probs, label_sim_dict])
# compile；
AdamLR = extend_with_piecewise_linear_lr(Adam, name='AdamLR')
self.model = Model(bert.model.input + [label_input], concat_output)
self.model.compile(loss=lcm_loss,
optimizer=AdamLR(learning_rate=1e-4,
lr_schedule={
1000: 1,
2000: 0.1
}))