Upload model
Browse files- config.json +6 -0
- configuration_transformer.py +59 -0
- model.safetensors +1 -1
- modeling_transformer.py +355 -0
config.json
CHANGED
@@ -2,6 +2,10 @@
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"architectures": [
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"transformerModel"
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],
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"batch_size": 64,
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"dropout": 0.1,
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"ffn_num_hiddens": 64,
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"num_layers": 2,
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"num_steps": 10,
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"query_size": 32,
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"torch_dtype": "float32",
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"transformers_version": "4.45.2",
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"value_size": 32
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"architectures": [
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"transformerModel"
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],
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"auto_map": {
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"AutoConfig": "configuration_transformer.transformerConfig",
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"AutoModel": "modeling_transformer.transformerModel"
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},
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"batch_size": 64,
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"dropout": 0.1,
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"ffn_num_hiddens": 64,
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"num_layers": 2,
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"num_steps": 10,
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"query_size": 32,
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"src_vocab_len": 184,
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"tgt_vocab": 201,
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"torch_dtype": "float32",
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"transformers_version": "4.45.2",
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"value_size": 32
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configuration_transformer.py
ADDED
@@ -0,0 +1,59 @@
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from transformers import PretrainedConfig
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class transformerConfig(PretrainedConfig):
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model_type = "custom_transformer"
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def __init__(
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self,
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src_vocab_len : int =184,
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tgt_vocab : int =201,
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num_hiddens : int =32,
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num_layers : int =2,
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dropout : int =0.1,
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batch_size : int =64,
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num_steps : int =10,
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lr : int =0.005,
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num_epochs : int =200,
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# device=d2l.try_gpu(),
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ffn_num_input : int =32,
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ffn_num_hiddens : int =64,
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num_heads : int =4,
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key_size : int =32,
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query_size : int =32,
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value_size : int =32,
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norm_shape : int =[32],
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# block_type="bottleneck",
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# layers: List[int] = [3, 4, 6, 3],
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# num_classes: int = 1000,
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# input_channels: int = 3,
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# cardinality: int = 1,
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# base_width: int = 64,
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# stem_width: int = 64,
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# stem_type: str = "",
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# avg_down: bool = False,
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**kwargs,
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):
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# if block_type not in ["basic", "bottleneck"]:
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# raise ValueError(f"`block_type` must be 'basic' or bottleneck', got {block_type}.")
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# if stem_type not in ["", "deep", "deep-tiered"]:
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# raise ValueError(f"`stem_type` must be '', 'deep' or 'deep-tiered', got {stem_type}.")
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self.src_vocab_len = src_vocab_len
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self.tgt_vocab = tgt_vocab
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self.num_hiddens = num_hiddens
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self.num_layers = num_layers
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self.dropout = dropout
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self.batch_size = batch_size
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self.num_steps = num_steps
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self.lr = lr
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self.num_epochs = num_epochs
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self.ffn_num_input = ffn_num_input
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self.ffn_num_hiddens = ffn_num_hiddens
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self.num_heads = num_heads
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self.key_size = key_size
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self.query_size = query_size
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self.value_size = value_size
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self.norm_shape = norm_shape
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super().__init__(**kwargs)
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model.safetensors
CHANGED
@@ -1,3 +1,3 @@
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version https://git-lfs.github.com/spec/v1
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-
oid sha256:
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size 250204
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version https://git-lfs.github.com/spec/v1
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+
oid sha256:b762859c138e7e8ccc36f5d3fee30bfacfba5417f6843a51a7087e607bd31173
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size 250204
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modeling_transformer.py
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from transformers import PreTrainedModel
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import math
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import pandas as pd
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import torch
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from torch import nn
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from d2l import torch as d2l
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#基于位置的前馈网络
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#@save
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class PositionWiseFFN(nn.Module):
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"""基于位置的前馈网络"""
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def __init__(self, ffn_num_input, ffn_num_hiddens, ffn_num_outputs,
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**kwargs):
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super(PositionWiseFFN, self).__init__(**kwargs)
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self.dense1 = nn.Linear(ffn_num_input, ffn_num_hiddens)
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self.relu = nn.ReLU()
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self.dense2 = nn.Linear(ffn_num_hiddens, ffn_num_outputs)
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def forward(self, X):
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return self.dense2(self.relu(self.dense1(X)))
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def transpose_qkv(X, num_heads):
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"""为了多注意力头的并行计算而变换形状
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Defined in :numref:`sec_multihead-attention`"""
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# 输入X的形状:(batch_size,查询或者“键-值”对的个数,num_hiddens)
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# 输出X的形状:(batch_size,查询或者“键-值”对的个数,num_heads,
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# num_hiddens/num_heads)
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X = X.reshape(X.shape[0], X.shape[1], num_heads, -1)
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# 输出X的形状:(batch_size,num_heads,查询或者“键-值”对的个数,
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# num_hiddens/num_heads)
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X = X.permute(0, 2, 1, 3)
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# 最终输出的形状:(batch_size*num_heads,查询或者“键-值”对的个数,
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# num_hiddens/num_heads)
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return X.reshape(-1, X.shape[2], X.shape[3])
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def transpose_output(X, num_heads):
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"""逆转transpose_qkv函数的操作
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Defined in :numref:`sec_multihead-attention`"""
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X = X.reshape(-1, num_heads, X.shape[1], X.shape[2])
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X = X.permute(0, 2, 1, 3)
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return X.reshape(X.shape[0], X.shape[1], -1)
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def sequence_mask(X, valid_len, value=0):
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"""在序列中屏蔽不相关的项
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Defined in :numref:`sec_seq2seq_decoder`"""
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maxlen = X.size(1)
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mask = torch.arange((maxlen), dtype=torch.float32,
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device=X.device)[None, :] < valid_len[:, None]
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X[~mask] = value
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return X
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def masked_softmax(X, valid_lens):
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"""通过在最后一个轴上掩蔽元素来执行softmax操作
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Defined in :numref:`sec_attention-scoring-functions`"""
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# X:3D张量,valid_lens:1D或2D张量
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if valid_lens is None:
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return nn.functional.softmax(X, dim=-1)
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else:
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shape = X.shape
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if valid_lens.dim() == 1:
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valid_lens = torch.repeat_interleave(valid_lens, shape[1])
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else:
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valid_lens = valid_lens.reshape(-1)
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# 最后一轴上被掩蔽的元素使用一个非常大的负值替换,从而其softmax输出为0
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X = sequence_mask(X.reshape(-1, shape[-1]), valid_lens,
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value=-1e6)
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return nn.functional.softmax(X.reshape(shape), dim=-1)
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class DotProductAttention(nn.Module):
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"""缩放点积注意力
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Defined in :numref:`subsec_additive-attention`"""
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def __init__(self, dropout, **kwargs):
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super(DotProductAttention, self).__init__(**kwargs)
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self.dropout = nn.Dropout(dropout)
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# queries的形状:(batch_size,查询的个数,d)
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# keys的形状:(batch_size,“键-值”对的个数,d)
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# values的形状:(batch_size,“键-值”对的个数,值的维度)
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# valid_lens的形状:(batch_size,)或者(batch_size,查询的个数)
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def forward(self, queries, keys, values, valid_lens=None):
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d = queries.shape[-1]
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# 设置transpose_b=True为了交换keys的最后两个维度
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scores = torch.bmm(queries, keys.transpose(1,2)) / math.sqrt(d)
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self.attention_weights = masked_softmax(scores, valid_lens)
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return torch.bmm(self.dropout(self.attention_weights), values)
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class MultiHeadAttention(nn.Module):
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"""多头注意力
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Defined in :numref:`sec_multihead-attention`"""
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def __init__(self, key_size, query_size, value_size, num_hiddens,
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num_heads, dropout, bias=False, **kwargs):
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super(MultiHeadAttention, self).__init__(**kwargs)
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self.num_heads = num_heads
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self.attention = DotProductAttention(dropout)
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self.W_q = nn.Linear(query_size, num_hiddens, bias=bias)
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self.W_k = nn.Linear(key_size, num_hiddens, bias=bias)
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self.W_v = nn.Linear(value_size, num_hiddens, bias=bias)
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self.W_o = nn.Linear(num_hiddens, num_hiddens, bias=bias)
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def forward(self, queries, keys, values, valid_lens):
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# queries,keys,values的形状:
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111 |
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# (batch_size,查询或者“键-值”对的个数,num_hiddens)
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112 |
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# valid_lens 的形状:
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113 |
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# (batch_size,)或(batch_size,查询的个数)
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114 |
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# 经过变换后,输出的queries,keys,values 的形状:
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# (batch_size*num_heads,查询或者“键-值”对的个数,
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# num_hiddens/num_heads)
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117 |
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queries = transpose_qkv(self.W_q(queries), self.num_heads)
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118 |
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keys = transpose_qkv(self.W_k(keys), self.num_heads)
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119 |
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values = transpose_qkv(self.W_v(values), self.num_heads)
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120 |
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121 |
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if valid_lens is not None:
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122 |
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# 在轴0,将第一项(标量或者矢量)复制num_heads次,
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123 |
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# 然后如此复制第二项,然后诸如此类。
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124 |
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valid_lens = torch.repeat_interleave(
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125 |
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valid_lens, repeats=self.num_heads, dim=0)
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126 |
+
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127 |
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# output的形状:(batch_size*num_heads,查询的个数,
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128 |
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# num_hiddens/num_heads)
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129 |
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output = self.attention(queries, keys, values, valid_lens)
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130 |
+
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131 |
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# output_concat的形状:(batch_size,查询的个数,num_hiddens)
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132 |
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output_concat = transpose_output(output, self.num_heads)
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133 |
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return self.W_o(output_concat)
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134 |
+
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135 |
+
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136 |
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#残差连接和层规范化
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137 |
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#@save
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138 |
+
class AddNorm(nn.Module):
|
139 |
+
"""残差连接后进行层规范化"""
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140 |
+
def __init__(self, normalized_shape, dropout, **kwargs):
|
141 |
+
super(AddNorm, self).__init__(**kwargs)
|
142 |
+
self.dropout = nn.Dropout(dropout)
|
143 |
+
self.ln = nn.LayerNorm(normalized_shape)
|
144 |
+
|
145 |
+
def forward(self, X, Y):
|
146 |
+
return self.ln(self.dropout(Y) + X)
|
147 |
+
|
148 |
+
#编码器,Transformer编码器中的任何层都不会改变其输入的形状
|
149 |
+
#@save
|
150 |
+
class EncoderBlock(nn.Module):
|
151 |
+
"""Transformer编码器块"""
|
152 |
+
def __init__(self, key_size, query_size, value_size, num_hiddens,
|
153 |
+
norm_shape, ffn_num_input, ffn_num_hiddens, num_heads,
|
154 |
+
dropout, use_bias=False, **kwargs):
|
155 |
+
super(EncoderBlock, self).__init__(**kwargs)
|
156 |
+
self.attention = MultiHeadAttention(
|
157 |
+
key_size, query_size, value_size, num_hiddens, num_heads, dropout,
|
158 |
+
use_bias)
|
159 |
+
self.addnorm1 = AddNorm(norm_shape, dropout)
|
160 |
+
self.ffn = PositionWiseFFN(
|
161 |
+
ffn_num_input, ffn_num_hiddens, num_hiddens)
|
162 |
+
self.addnorm2 = AddNorm(norm_shape, dropout)
|
163 |
+
|
164 |
+
def forward(self, X, valid_lens):
|
165 |
+
Y = self.addnorm1(X, self.attention(X, X, X, valid_lens))
|
166 |
+
return self.addnorm2(Y, self.ffn(Y))
|
167 |
+
|
168 |
+
class PositionalEncoding(nn.Module):
|
169 |
+
"""位置编码
|
170 |
+
|
171 |
+
Defined in :numref:`sec_self-attention-and-positional-encoding`"""
|
172 |
+
def __init__(self, num_hiddens, dropout, max_len=1000):
|
173 |
+
super(PositionalEncoding, self).__init__()
|
174 |
+
self.dropout = nn.Dropout(dropout)
|
175 |
+
# 创建一个足够长的P
|
176 |
+
self.P = torch.zeros((1, max_len, num_hiddens))
|
177 |
+
X = torch.arange(max_len, dtype=torch.float32).reshape(
|
178 |
+
-1, 1) / torch.pow(10000, torch.arange(
|
179 |
+
0, num_hiddens, 2, dtype=torch.float32) / num_hiddens)
|
180 |
+
self.P[:, :, 0::2] = torch.sin(X)
|
181 |
+
self.P[:, :, 1::2] = torch.cos(X)
|
182 |
+
|
183 |
+
def forward(self, X):
|
184 |
+
X = X + self.P[:, :X.shape[1], :].to(X.device)
|
185 |
+
return self.dropout(X)
|
186 |
+
|
187 |
+
class Encoder(nn.Module):
|
188 |
+
"""编码器-解码器架构的基本编码器接口"""
|
189 |
+
def __init__(self, **kwargs):
|
190 |
+
super(Encoder, self).__init__(**kwargs)
|
191 |
+
|
192 |
+
def forward(self, X, *args):
|
193 |
+
raise NotImplementedError
|
194 |
+
|
195 |
+
|
196 |
+
|
197 |
+
###解码器
|
198 |
+
class DecoderBlock(nn.Module):
|
199 |
+
"""解码器中第i个块"""
|
200 |
+
def __init__(self, key_size, query_size, value_size, num_hiddens,
|
201 |
+
norm_shape, ffn_num_input, ffn_num_hiddens, num_heads,
|
202 |
+
dropout, i, **kwargs):
|
203 |
+
super(DecoderBlock, self).__init__(**kwargs)
|
204 |
+
self.i = i
|
205 |
+
self.attention1 = MultiHeadAttention(
|
206 |
+
key_size, query_size, value_size, num_hiddens, num_heads, dropout)
|
207 |
+
self.addnorm1 = AddNorm(norm_shape, dropout)
|
208 |
+
self.attention2 = MultiHeadAttention(
|
209 |
+
key_size, query_size, value_size, num_hiddens, num_heads, dropout)
|
210 |
+
self.addnorm2 = AddNorm(norm_shape, dropout)
|
211 |
+
self.ffn = PositionWiseFFN(ffn_num_input, ffn_num_hiddens,
|
212 |
+
num_hiddens)
|
213 |
+
self.addnorm3 = AddNorm(norm_shape, dropout)
|
214 |
+
|
215 |
+
def forward(self, X, state):
|
216 |
+
enc_outputs, enc_valid_lens = state[0], state[1]
|
217 |
+
# 训练阶段,输出序列的所有词元都在同一时间处理,
|
218 |
+
# 因此state[2][self.i]初始化为None。
|
219 |
+
# 预测阶段,输出序列是通过词元一个接着一个解码的,
|
220 |
+
# 因此state[2][self.i]包含着直到当前时间步第i个块解码的输出表示
|
221 |
+
if state[2][self.i] is None:
|
222 |
+
key_values = X
|
223 |
+
else:
|
224 |
+
key_values = torch.cat((state[2][self.i], X), axis=1)
|
225 |
+
state[2][self.i] = key_values
|
226 |
+
if self.training:
|
227 |
+
batch_size, num_steps, _ = X.shape
|
228 |
+
# dec_valid_lens的开头:(batch_size,num_steps),
|
229 |
+
# 其中每一行是[1,2,...,num_steps]
|
230 |
+
dec_valid_lens = torch.arange(
|
231 |
+
1, num_steps + 1, device=X.device).repeat(batch_size, 1)
|
232 |
+
else:
|
233 |
+
dec_valid_lens = None
|
234 |
+
|
235 |
+
# 自注意力
|
236 |
+
X2 = self.attention1(X, key_values, key_values, dec_valid_lens)
|
237 |
+
Y = self.addnorm1(X, X2)
|
238 |
+
# 编码器-解码器注意力。
|
239 |
+
# enc_outputs的开头:(batch_size,num_steps,num_hiddens)
|
240 |
+
Y2 = self.attention2(Y, enc_outputs, enc_outputs, enc_valid_lens)
|
241 |
+
Z = self.addnorm2(Y, Y2)
|
242 |
+
return self.addnorm3(Z, self.ffn(Z)), state
|
243 |
+
|
244 |
+
class Decoder(nn.Module):
|
245 |
+
"""编码器-解码器架构的基本解码器接口
|
246 |
+
|
247 |
+
Defined in :numref:`sec_encoder-decoder`"""
|
248 |
+
def __init__(self, **kwargs):
|
249 |
+
super(Decoder, self).__init__(**kwargs)
|
250 |
+
|
251 |
+
def init_state(self, enc_outputs, *args):
|
252 |
+
raise NotImplementedError
|
253 |
+
|
254 |
+
def forward(self, X, state):
|
255 |
+
raise NotImplementedError
|
256 |
+
|
257 |
+
class AttentionDecoder(Decoder):
|
258 |
+
"""带有注意力机制解码器的基本接口
|
259 |
+
|
260 |
+
Defined in :numref:`sec_seq2seq_attention`"""
|
261 |
+
def __init__(self, **kwargs):
|
262 |
+
super(AttentionDecoder, self).__init__(**kwargs)
|
263 |
+
|
264 |
+
@property
|
265 |
+
def attention_weights(self):
|
266 |
+
raise NotImplementedError
|
267 |
+
|
268 |
+
|
269 |
+
#@save
|
270 |
+
class TransformerEncoder(Encoder):
|
271 |
+
"""Transformer编码器"""
|
272 |
+
def __init__(self, vocab_size, key_size, query_size, value_size,
|
273 |
+
num_hiddens, norm_shape, ffn_num_input, ffn_num_hiddens,
|
274 |
+
num_heads, num_layers, dropout, use_bias=False, **kwargs):
|
275 |
+
super(TransformerEncoder, self).__init__(**kwargs)
|
276 |
+
self.num_hiddens = num_hiddens
|
277 |
+
self.embedding = nn.Embedding(vocab_size, num_hiddens)
|
278 |
+
self.pos_encoding = PositionalEncoding(num_hiddens, dropout)
|
279 |
+
self.blks = nn.Sequential()
|
280 |
+
for i in range(num_layers):
|
281 |
+
self.blks.add_module("block"+str(i),
|
282 |
+
EncoderBlock(key_size, query_size, value_size, num_hiddens,
|
283 |
+
norm_shape, ffn_num_input, ffn_num_hiddens,
|
284 |
+
num_heads, dropout, use_bias))
|
285 |
+
|
286 |
+
def forward(self, X, valid_lens, *args):
|
287 |
+
# 因为位置编码值在-1和1之间,
|
288 |
+
# 因此嵌入值乘以嵌入维度的平方根进行缩放,
|
289 |
+
# 然后再与位置编码相加。
|
290 |
+
X = self.pos_encoding(self.embedding(X) * math.sqrt(self.num_hiddens))
|
291 |
+
self.attention_weights = [None] * len(self.blks)
|
292 |
+
for i, blk in enumerate(self.blks):
|
293 |
+
X = blk(X, valid_lens)
|
294 |
+
self.attention_weights[
|
295 |
+
i] = blk.attention.attention.attention_weights
|
296 |
+
return X
|
297 |
+
|
298 |
+
|
299 |
+
class TransformerDecoder(AttentionDecoder):
|
300 |
+
def __init__(self, vocab_size, key_size, query_size, value_size,
|
301 |
+
num_hiddens, norm_shape, ffn_num_input, ffn_num_hiddens,
|
302 |
+
num_heads, num_layers, dropout, **kwargs):
|
303 |
+
super(TransformerDecoder, self).__init__(**kwargs)
|
304 |
+
self.num_hiddens = num_hiddens
|
305 |
+
self.num_layers = num_layers
|
306 |
+
self.embedding = nn.Embedding(vocab_size, num_hiddens)
|
307 |
+
self.pos_encoding = PositionalEncoding(num_hiddens, dropout)
|
308 |
+
self.blks = nn.Sequential()
|
309 |
+
for i in range(num_layers):
|
310 |
+
self.blks.add_module("block"+str(i),
|
311 |
+
DecoderBlock(key_size, query_size, value_size, num_hiddens,
|
312 |
+
norm_shape, ffn_num_input, ffn_num_hiddens,
|
313 |
+
num_heads, dropout, i))
|
314 |
+
self.dense = nn.Linear(num_hiddens, vocab_size)
|
315 |
+
|
316 |
+
def init_state(self, enc_outputs, enc_valid_lens, *args):
|
317 |
+
return [enc_outputs, enc_valid_lens, [None] * self.num_layers]
|
318 |
+
|
319 |
+
def forward(self, X, state):
|
320 |
+
X = self.pos_encoding(self.embedding(X) * math.sqrt(self.num_hiddens))
|
321 |
+
self._attention_weights = [[None] * len(self.blks) for _ in range (2)]
|
322 |
+
for i, blk in enumerate(self.blks):
|
323 |
+
X, state = blk(X, state)
|
324 |
+
# 解码器自注意力权重
|
325 |
+
self._attention_weights[0][
|
326 |
+
i] = blk.attention1.attention.attention_weights
|
327 |
+
# “编码器-解码器”自注意力权重
|
328 |
+
self._attention_weights[1][
|
329 |
+
i] = blk.attention2.attention.attention_weights
|
330 |
+
return self.dense(X), state
|
331 |
+
|
332 |
+
@property
|
333 |
+
def attention_weights(self):
|
334 |
+
return self._attention_weights
|
335 |
+
|
336 |
+
|
337 |
+
class transformerModel(PreTrainedModel):
|
338 |
+
"""编码器-解码器架构的基类
|
339 |
+
Defined in :numref:`sec_encoder-decoder`"""
|
340 |
+
def __init__(self, config):
|
341 |
+
super().__init__(config)
|
342 |
+
self.encoder = TransformerEncoder(
|
343 |
+
config.src_vocab_len, config.key_size, config.query_size, config.value_size, config.num_hiddens,
|
344 |
+
config.norm_shape, config.ffn_num_input, config.ffn_num_hiddens, config.num_heads,
|
345 |
+
config.num_layers, config.dropout)
|
346 |
+
|
347 |
+
self.decoder = TransformerDecoder(
|
348 |
+
config.tgt_vocab, config.key_size, config.query_size, config.value_size, config.num_hiddens,
|
349 |
+
config.norm_shape, config.ffn_num_input, config.ffn_num_hiddens, config.num_heads,
|
350 |
+
config.num_layers, config.dropout)
|
351 |
+
|
352 |
+
def forward(self, enc_X, dec_X, *args):
|
353 |
+
enc_outputs = self.encoder(enc_X, *args)
|
354 |
+
dec_state = self.decoder.init_state(enc_outputs, *args)
|
355 |
+
return self.decoder(dec_X, dec_state)
|