107 lines
3.9 KiB
Python
107 lines
3.9 KiB
Python
# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License"
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
import abc
|
|
|
|
import paddle
|
|
import paddle.nn as nn
|
|
import paddle.nn.functional as F
|
|
|
|
|
|
class SemanticIndexBase(nn.Layer):
|
|
def __init__(self, pretrained_model, dropout=None, output_emb_size=None, use_fp16=False):
|
|
super().__init__()
|
|
self.ptm = pretrained_model
|
|
self.dropout = nn.Dropout(dropout if dropout is not None else 0.1)
|
|
|
|
# if output_emb_size is not None, then add Linear layer to reduce embedding_size,
|
|
# we recommend set output_emb_size = 256 considering the trade-off between
|
|
# recall performance and efficiency
|
|
|
|
self.output_emb_size = output_emb_size
|
|
if output_emb_size > 0:
|
|
weight_attr = paddle.ParamAttr(initializer=paddle.nn.initializer.TruncatedNormal(std=0.02))
|
|
self.emb_reduce_linear = paddle.nn.Linear(768, output_emb_size, weight_attr=weight_attr)
|
|
|
|
self.use_fp16 = use_fp16
|
|
|
|
def get_pooled_embedding(self, input_ids, token_type_ids=None, position_ids=None, attention_mask=None):
|
|
|
|
if self.use_fp16:
|
|
if attention_mask is None:
|
|
attention_mask = paddle.unsqueeze(
|
|
(input_ids == self.ptm.pad_token_id).astype(self.ptm.pooler.dense.weight.dtype) * -1e4, axis=[1, 2]
|
|
)
|
|
|
|
embedding_output = self.ptm.embeddings(
|
|
input_ids=input_ids, position_ids=position_ids, token_type_ids=token_type_ids
|
|
)
|
|
|
|
embedding_output = paddle.cast(embedding_output, "float16")
|
|
attention_mask = paddle.cast(attention_mask, "float16")
|
|
|
|
encoder_outputs = self.ptm.encoder(embedding_output, attention_mask)
|
|
|
|
if self.use_fp16:
|
|
encoder_outputs = paddle.cast(encoder_outputs, "float32")
|
|
cls_embedding = self.ptm.pooler(encoder_outputs)
|
|
else:
|
|
_, cls_embedding = self.ptm(input_ids, token_type_ids, position_ids, attention_mask)
|
|
|
|
if self.output_emb_size > 0:
|
|
cls_embedding = self.emb_reduce_linear(cls_embedding)
|
|
cls_embedding = self.dropout(cls_embedding)
|
|
cls_embedding = F.normalize(cls_embedding, p=2, axis=-1)
|
|
|
|
return cls_embedding
|
|
|
|
def get_semantic_embedding(self, data_loader):
|
|
self.eval()
|
|
with paddle.no_grad():
|
|
for batch_data in data_loader:
|
|
input_ids, token_type_ids = batch_data
|
|
input_ids = paddle.to_tensor(input_ids)
|
|
token_type_ids = paddle.to_tensor(token_type_ids)
|
|
|
|
text_embeddings = self.get_pooled_embedding(input_ids, token_type_ids=token_type_ids)
|
|
|
|
yield text_embeddings
|
|
|
|
def cosine_sim(
|
|
self,
|
|
query_input_ids,
|
|
title_input_ids,
|
|
query_token_type_ids=None,
|
|
query_position_ids=None,
|
|
query_attention_mask=None,
|
|
title_token_type_ids=None,
|
|
title_position_ids=None,
|
|
title_attention_mask=None,
|
|
):
|
|
|
|
query_cls_embedding = self.get_pooled_embedding(
|
|
query_input_ids, query_token_type_ids, query_position_ids, query_attention_mask
|
|
)
|
|
|
|
title_cls_embedding = self.get_pooled_embedding(
|
|
title_input_ids, title_token_type_ids, title_position_ids, title_attention_mask
|
|
)
|
|
|
|
cosine_sim = paddle.sum(query_cls_embedding * title_cls_embedding, axis=-1)
|
|
return cosine_sim
|
|
|
|
@abc.abstractmethod
|
|
def forward(self):
|
|
pass
|