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Update app/model_def.py
Browse files- app/model_def.py +242 -242
app/model_def.py
CHANGED
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@@ -1,243 +1,243 @@
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import torch
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import torch.nn as nn
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import math
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class InputEmbedding(nn.Module):
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def __init__(self, d_model: int, vocab_size: int):
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super().__init__()
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self.d_model = d_model
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self.vocab_size = vocab_size
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self.embed = nn.Embedding(vocab_size, d_model)
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def forward(self, x):
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return self.embed(x) * math.sqrt(self.d_model)
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class PositionalEncoding(nn.Module):
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def __init__(self, d_model: int, seq_len: int, dropout: float):
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super().__init__()
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self.d_model = d_model
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self.seq_len = seq_len
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self.dropout = nn.Dropout(dropout)
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# Create a matrix of shape (seq_len, d_model)
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pe = torch.zeros(seq_len, d_model)
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# Create a vector of shape (seq_len, 1)
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position = torch.arange(0, seq_len, dtype=torch.float).unsqueeze(1)
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div_term = torch.exp(torch.arange(0, d_model, 2).float() * (-math.log(10000.0) / d_model))
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# Apply sin to even indices
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pe[:, 0::2] = torch.sin(position * div_term)
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# Apply cos to odd indices
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pe[:, 1::2] = torch.cos(position * div_term)
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# Add a batch dimension
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pe = pe.unsqueeze(0) # (1, seq_len, d_model)
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# Register 'pe' as a buffer, so it's not a model parameter
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self.register_buffer('pe', pe)
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def forward(self, x):
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x = x + (self.pe[:, :x.shape[1], :]).requires_grad_(False)
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return self.dropout(x)
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class LayerNorm(nn.Module):
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def __init__(self, d_model: int, epsilon: float = 1e-6):
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super().__init__()
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self.epsilon = epsilon
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self.gamma = nn.Parameter(torch.ones(d_model)) # Multiplicative
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self.beta = nn.Parameter(torch.zeros(d_model)) # Additive
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def forward(self, x):
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mean = x.mean(dim=-1, keepdim=True)
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std = x.std(dim=-1, keepdim=True)
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return self.gamma * (x - mean) / (std + self.epsilon) + self.beta
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class FeedForward(nn.Module):
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def __init__(self, d_model: int, d_ff: int, dropout: float):
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super().__init__()
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self.layer1 = nn.Linear(d_model, d_ff)
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self.layer2 = nn.Linear(d_ff, d_model)
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self.dropout = nn.Dropout(dropout)
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def forward(self, x):
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# (Batch, Seq_Len, d_model) -> (Batch, Seq_Len, d_ff) -> (Batch, Seq_Len, d_model)
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return self.layer2(self.dropout(torch.relu(self.layer1(x))))
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class MHA(nn.Module):
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def __init__(self, d_model: int, h: int, dropout: float):
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super().__init__()
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self.d_model = d_model
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self.h = h
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assert d_model % h == 0, "d_model must be divisible by h"
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self.d_k = d_model // h
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self.w_q = nn.Linear(d_model, d_model)
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self.w_k = nn.Linear(d_model, d_model)
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self.w_v = nn.Linear(d_model, d_model)
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self.w_o = nn.Linear(d_model, d_model)
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self.dropout = nn.Dropout(dropout)
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@staticmethod
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def attention(query, key, value, mask, dropout: nn.Dropout):
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d_k = query.shape[-1]
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attention_scores = (query @ key.transpose(-2, -1)) / math.sqrt(d_k)
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if mask is not None:
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attention_scores = attention_scores.masked_fill(mask == 0, -1e9)
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attention_scores = attention_scores.softmax(dim=-1)
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if dropout is not None:
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attention_scores = dropout(attention_scores)
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return (attention_scores @ value), attention_scores
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def forward(self, q, k, v, mask):
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query = self.w_q(q) # (Batch, Seq_Len, d_model)
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key = self.w_k(k) # (Batch, Seq_Len, d_model)
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value = self.w_v(v) # (Batch, Seq_Len, d_model)
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# (Batch, Seq_Len, d_model) -> (Batch, Seq_Len, h, d_k) -> (Batch, h, Seq_Len, d_k)
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query = query.view(query.shape[0], query.shape[1], self.h, self.d_k).transpose(1, 2)
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key = key.view(key.shape[0], key.shape[1], self.h, self.d_k).transpose(1, 2)
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value = value.view(value.shape[0], value.shape[1], self.h, self.d_k).transpose(1, 2)
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x, self.attention_scores = MHA.attention(query, key, value, mask, self.dropout)
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# (Batch, h, Seq_Len, d_k) -> (Batch, Seq_Len, h, d_k) -> (Batch, Seq_Len, d_model)
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x = x.transpose(1, 2).contiguous().view(x.shape[0], -1, self.h * self.d_k)
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return self.w_o(x)
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class SkipConnection(nn.Module):
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def __init__(self, d_model: int, dropout: float):
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super().__init__()
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self.dropout = nn.Dropout(dropout)
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self.norm = LayerNorm(d_model)
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def forward(self, x, sublayer):
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# Pre-Norm architecture
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return x + self.dropout(sublayer(self.norm(x)))
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class EncoderBlock(nn.Module):
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def __init__(self, self_attention: MHA, ffn: FeedForward, d_model: int, dropout: float):
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super().__init__()
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self.
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self.ffn = ffn
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self.
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def forward(self, x, src_mask):
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x = self.
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x = self.
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return x
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class Encoder(nn.Module):
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def __init__(self, d_model: int, layers: nn.ModuleList):
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super().__init__()
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self.layers = layers
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self.norm = LayerNorm(d_model)
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def forward(self, x, mask):
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for layer in self.layers:
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x = layer(x, mask)
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return self.norm(x)
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class DecoderBlock(nn.Module):
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def __init__(self, self_attention: MHA, cross_attention: MHA, ffn: FeedForward, d_model: int, dropout: float):
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super().__init__()
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self.
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self.cross_attention = cross_attention
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self.ffn = ffn
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self.
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def forward(self, x, encoder_output, src_mask, trg_mask):
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x = self.
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x = self.
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x = self.
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return x
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class Decoder(nn.Module):
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def __init__(self, d_model: int, layers: nn.ModuleList):
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super().__init__()
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self.layers = layers
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self.norm = LayerNorm(d_model)
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def forward(self, x, encoder_output, src_mask, trg_mask):
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for layer in self.layers:
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x = layer(x, encoder_output, src_mask, trg_mask)
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return self.norm(x)
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class Output(nn.Module):
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def __init__(self, d_model: int, vocab_size: int):
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super().__init__()
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self.proj = nn.Linear(d_model, vocab_size)
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def forward(self, x):
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# (Batch, Seq_Len, d_model) -> (Batch, Seq_Len, vocab_size)
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return self.proj(x)
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class Transformer(nn.Module):
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def __init__(self, encoder: Encoder, decoder: Decoder, src_embed: InputEmbedding, trg_embed: InputEmbedding, src_pos: PositionalEncoding, trg_pos: PositionalEncoding, output: Output):
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super().__init__()
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self.encoder = encoder
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self.decoder = decoder
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self.src_embed = src_embed
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self.trg_embed = trg_embed
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self.src_pos = src_pos
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self.trg_pos = trg_pos
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self.output_layer = output
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def encode(self, src, src_mask):
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src = self.src_embed(src)
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src = self.src_pos(src)
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return self.encoder(src, src_mask)
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def decode(self, encoder_output, src_mask, trg, trg_mask):
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trg = self.trg_embed(trg)
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trg = self.trg_pos(trg)
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return self.decoder(trg, encoder_output, src_mask, trg_mask)
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def project(self, x):
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return self.output_layer(x)
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def BuildTransformer(src_vocab_size: int, trg_vocab_size: int, src_seq_len: int, trg_seq_len: int, d_model: int = 512, N: int = 6, h: int = 8, dropout: float = 0.1, d_ff: int = 2048) -> Transformer:
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# Create the embedding layers
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src_embed = InputEmbedding(d_model, src_vocab_size)
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trg_embed = InputEmbedding(d_model, trg_vocab_size)
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# Create the positional encoding layers
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src_pos = PositionalEncoding(d_model, src_seq_len, dropout)
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trg_pos = PositionalEncoding(d_model, trg_seq_len, dropout)
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# Create the encoder blocks
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encoder_blocks = []
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for _ in range(N):
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encoder_self_attention = MHA(d_model, h, dropout)
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ffn = FeedForward(d_model, d_ff, dropout)
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encoder_block = EncoderBlock(encoder_self_attention, ffn, d_model, dropout)
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encoder_blocks.append(encoder_block)
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# Create the decoder blocks
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decoder_blocks = []
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for _ in range(N):
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decoder_self_attention = MHA(d_model, h, dropout)
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cross_attention = MHA(d_model, h, dropout)
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ffn = FeedForward(d_model, d_ff, dropout)
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decoder_block = DecoderBlock(decoder_self_attention, cross_attention, ffn, d_model, dropout)
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decoder_blocks.append(decoder_block)
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# Create the encoder and decoder
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encoder = Encoder(d_model, nn.ModuleList(encoder_blocks))
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decoder = Decoder(d_model, nn.ModuleList(decoder_blocks))
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# Create the projection layer
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projection = Output(d_model, trg_vocab_size)
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# Create the transformer
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transformer = Transformer(encoder, decoder, src_embed, trg_embed, src_pos, trg_pos, projection)
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# Initialize parameters
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for p in transformer.parameters():
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if p.dim() > 1:
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nn.init.xavier_uniform_(p)
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return transformer
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import torch
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import torch.nn as nn
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import math
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class InputEmbedding(nn.Module):
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def __init__(self, d_model: int, vocab_size: int):
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super().__init__()
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self.d_model = d_model
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self.vocab_size = vocab_size
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self.embed = nn.Embedding(vocab_size, d_model)
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def forward(self, x):
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return self.embed(x) * math.sqrt(self.d_model)
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class PositionalEncoding(nn.Module):
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def __init__(self, d_model: int, seq_len: int, dropout: float):
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super().__init__()
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self.d_model = d_model
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self.seq_len = seq_len
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self.dropout = nn.Dropout(dropout)
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# Create a matrix of shape (seq_len, d_model)
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pe = torch.zeros(seq_len, d_model)
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# Create a vector of shape (seq_len, 1)
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position = torch.arange(0, seq_len, dtype=torch.float).unsqueeze(1)
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div_term = torch.exp(torch.arange(0, d_model, 2).float() * (-math.log(10000.0) / d_model))
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# Apply sin to even indices
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pe[:, 0::2] = torch.sin(position * div_term)
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# Apply cos to odd indices
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pe[:, 1::2] = torch.cos(position * div_term)
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# Add a batch dimension
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pe = pe.unsqueeze(0) # (1, seq_len, d_model)
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# Register 'pe' as a buffer, so it's not a model parameter
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self.register_buffer('pe', pe)
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def forward(self, x):
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x = x + (self.pe[:, :x.shape[1], :]).requires_grad_(False)
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return self.dropout(x)
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class LayerNorm(nn.Module):
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def __init__(self, d_model: int, epsilon: float = 1e-6):
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super().__init__()
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self.epsilon = epsilon
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self.gamma = nn.Parameter(torch.ones(d_model)) # Multiplicative
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self.beta = nn.Parameter(torch.zeros(d_model)) # Additive
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def forward(self, x):
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mean = x.mean(dim=-1, keepdim=True)
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std = x.std(dim=-1, keepdim=True)
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return self.gamma * (x - mean) / (std + self.epsilon) + self.beta
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class FeedForward(nn.Module):
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def __init__(self, d_model: int, d_ff: int, dropout: float):
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super().__init__()
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self.layer1 = nn.Linear(d_model, d_ff)
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self.layer2 = nn.Linear(d_ff, d_model)
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self.dropout = nn.Dropout(dropout)
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def forward(self, x):
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# (Batch, Seq_Len, d_model) -> (Batch, Seq_Len, d_ff) -> (Batch, Seq_Len, d_model)
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return self.layer2(self.dropout(torch.relu(self.layer1(x))))
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class MHA(nn.Module):
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def __init__(self, d_model: int, h: int, dropout: float):
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super().__init__()
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self.d_model = d_model
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self.h = h
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assert d_model % h == 0, "d_model must be divisible by h"
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self.d_k = d_model // h
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self.w_q = nn.Linear(d_model, d_model)
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self.w_k = nn.Linear(d_model, d_model)
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self.w_v = nn.Linear(d_model, d_model)
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self.w_o = nn.Linear(d_model, d_model)
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self.dropout = nn.Dropout(dropout)
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@staticmethod
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def attention(query, key, value, mask, dropout: nn.Dropout):
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d_k = query.shape[-1]
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attention_scores = (query @ key.transpose(-2, -1)) / math.sqrt(d_k)
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if mask is not None:
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attention_scores = attention_scores.masked_fill(mask == 0, -1e9)
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attention_scores = attention_scores.softmax(dim=-1)
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if dropout is not None:
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attention_scores = dropout(attention_scores)
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return (attention_scores @ value), attention_scores
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def forward(self, q, k, v, mask):
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query = self.w_q(q) # (Batch, Seq_Len, d_model)
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key = self.w_k(k) # (Batch, Seq_Len, d_model)
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value = self.w_v(v) # (Batch, Seq_Len, d_model)
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| 99 |
+
# (Batch, Seq_Len, d_model) -> (Batch, Seq_Len, h, d_k) -> (Batch, h, Seq_Len, d_k)
|
| 100 |
+
query = query.view(query.shape[0], query.shape[1], self.h, self.d_k).transpose(1, 2)
|
| 101 |
+
key = key.view(key.shape[0], key.shape[1], self.h, self.d_k).transpose(1, 2)
|
| 102 |
+
value = value.view(value.shape[0], value.shape[1], self.h, self.d_k).transpose(1, 2)
|
| 103 |
+
|
| 104 |
+
x, self.attention_scores = MHA.attention(query, key, value, mask, self.dropout)
|
| 105 |
+
|
| 106 |
+
# (Batch, h, Seq_Len, d_k) -> (Batch, Seq_Len, h, d_k) -> (Batch, Seq_Len, d_model)
|
| 107 |
+
x = x.transpose(1, 2).contiguous().view(x.shape[0], -1, self.h * self.d_k)
|
| 108 |
+
|
| 109 |
+
return self.w_o(x)
|
| 110 |
+
|
| 111 |
+
class SkipConnection(nn.Module):
|
| 112 |
+
def __init__(self, d_model: int, dropout: float):
|
| 113 |
+
super().__init__()
|
| 114 |
+
self.dropout = nn.Dropout(dropout)
|
| 115 |
+
self.norm = LayerNorm(d_model)
|
| 116 |
+
|
| 117 |
+
def forward(self, x, sublayer):
|
| 118 |
+
# Pre-Norm architecture
|
| 119 |
+
return x + self.dropout(sublayer(self.norm(x)))
|
| 120 |
+
|
| 121 |
+
class EncoderBlock(nn.Module):
|
| 122 |
+
def __init__(self, self_attention: MHA, ffn: FeedForward, d_model: int, dropout: float):
|
| 123 |
+
super().__init__()
|
| 124 |
+
self.attention = self_attention
|
| 125 |
+
self.ffn = ffn
|
| 126 |
+
self.residual = nn.ModuleList([SkipConnection(d_model, dropout) for _ in range(2)])
|
| 127 |
+
|
| 128 |
+
def forward(self, x, src_mask):
|
| 129 |
+
x = self.residual[0](x, lambda x: self.attention(x, x, x, src_mask))
|
| 130 |
+
x = self.residual[1](x, self.ffn)
|
| 131 |
+
return x
|
| 132 |
+
|
| 133 |
+
class Encoder(nn.Module):
|
| 134 |
+
def __init__(self, d_model: int, layers: nn.ModuleList):
|
| 135 |
+
super().__init__()
|
| 136 |
+
self.layers = layers
|
| 137 |
+
self.norm = LayerNorm(d_model)
|
| 138 |
+
|
| 139 |
+
def forward(self, x, mask):
|
| 140 |
+
for layer in self.layers:
|
| 141 |
+
x = layer(x, mask)
|
| 142 |
+
return self.norm(x)
|
| 143 |
+
|
| 144 |
+
class DecoderBlock(nn.Module):
|
| 145 |
+
def __init__(self, self_attention: MHA, cross_attention: MHA, ffn: FeedForward, d_model: int, dropout: float):
|
| 146 |
+
super().__init__()
|
| 147 |
+
self.attention = self_attention
|
| 148 |
+
self.cross_attention = cross_attention
|
| 149 |
+
self.ffn = ffn
|
| 150 |
+
self.residual = nn.ModuleList([SkipConnection(d_model, dropout) for _ in range(3)])
|
| 151 |
+
|
| 152 |
+
def forward(self, x, encoder_output, src_mask, trg_mask):
|
| 153 |
+
x = self.residual[0](x, lambda x: self.attention(x, x, x, trg_mask))
|
| 154 |
+
x = self.residual[1](x, lambda x: self.cross_attention(x, encoder_output, encoder_output, src_mask))
|
| 155 |
+
x = self.residual[2](x, self.ffn)
|
| 156 |
+
return x
|
| 157 |
+
|
| 158 |
+
class Decoder(nn.Module):
|
| 159 |
+
def __init__(self, d_model: int, layers: nn.ModuleList):
|
| 160 |
+
super().__init__()
|
| 161 |
+
self.layers = layers
|
| 162 |
+
self.norm = LayerNorm(d_model)
|
| 163 |
+
|
| 164 |
+
def forward(self, x, encoder_output, src_mask, trg_mask):
|
| 165 |
+
for layer in self.layers:
|
| 166 |
+
x = layer(x, encoder_output, src_mask, trg_mask)
|
| 167 |
+
return self.norm(x)
|
| 168 |
+
|
| 169 |
+
class Output(nn.Module):
|
| 170 |
+
def __init__(self, d_model: int, vocab_size: int):
|
| 171 |
+
super().__init__()
|
| 172 |
+
self.proj = nn.Linear(d_model, vocab_size)
|
| 173 |
+
|
| 174 |
+
def forward(self, x):
|
| 175 |
+
# (Batch, Seq_Len, d_model) -> (Batch, Seq_Len, vocab_size)
|
| 176 |
+
return self.proj(x)
|
| 177 |
+
|
| 178 |
+
class Transformer(nn.Module):
|
| 179 |
+
def __init__(self, encoder: Encoder, decoder: Decoder, src_embed: InputEmbedding, trg_embed: InputEmbedding, src_pos: PositionalEncoding, trg_pos: PositionalEncoding, output: Output):
|
| 180 |
+
super().__init__()
|
| 181 |
+
self.encoder = encoder
|
| 182 |
+
self.decoder = decoder
|
| 183 |
+
self.src_embed = src_embed
|
| 184 |
+
self.trg_embed = trg_embed
|
| 185 |
+
self.src_pos = src_pos
|
| 186 |
+
self.trg_pos = trg_pos
|
| 187 |
+
self.output_layer = output
|
| 188 |
+
|
| 189 |
+
def encode(self, src, src_mask):
|
| 190 |
+
src = self.src_embed(src)
|
| 191 |
+
src = self.src_pos(src)
|
| 192 |
+
return self.encoder(src, src_mask)
|
| 193 |
+
|
| 194 |
+
def decode(self, encoder_output, src_mask, trg, trg_mask):
|
| 195 |
+
trg = self.trg_embed(trg)
|
| 196 |
+
trg = self.trg_pos(trg)
|
| 197 |
+
return self.decoder(trg, encoder_output, src_mask, trg_mask)
|
| 198 |
+
|
| 199 |
+
def project(self, x):
|
| 200 |
+
return self.output_layer(x)
|
| 201 |
+
|
| 202 |
+
def BuildTransformer(src_vocab_size: int, trg_vocab_size: int, src_seq_len: int, trg_seq_len: int, d_model: int = 512, N: int = 6, h: int = 8, dropout: float = 0.1, d_ff: int = 2048) -> Transformer:
|
| 203 |
+
# Create the embedding layers
|
| 204 |
+
src_embed = InputEmbedding(d_model, src_vocab_size)
|
| 205 |
+
trg_embed = InputEmbedding(d_model, trg_vocab_size)
|
| 206 |
+
|
| 207 |
+
# Create the positional encoding layers
|
| 208 |
+
src_pos = PositionalEncoding(d_model, src_seq_len, dropout)
|
| 209 |
+
trg_pos = PositionalEncoding(d_model, trg_seq_len, dropout)
|
| 210 |
+
|
| 211 |
+
# Create the encoder blocks
|
| 212 |
+
encoder_blocks = []
|
| 213 |
+
for _ in range(N):
|
| 214 |
+
encoder_self_attention = MHA(d_model, h, dropout)
|
| 215 |
+
ffn = FeedForward(d_model, d_ff, dropout)
|
| 216 |
+
encoder_block = EncoderBlock(encoder_self_attention, ffn, d_model, dropout)
|
| 217 |
+
encoder_blocks.append(encoder_block)
|
| 218 |
+
|
| 219 |
+
# Create the decoder blocks
|
| 220 |
+
decoder_blocks = []
|
| 221 |
+
for _ in range(N):
|
| 222 |
+
decoder_self_attention = MHA(d_model, h, dropout)
|
| 223 |
+
cross_attention = MHA(d_model, h, dropout)
|
| 224 |
+
ffn = FeedForward(d_model, d_ff, dropout)
|
| 225 |
+
decoder_block = DecoderBlock(decoder_self_attention, cross_attention, ffn, d_model, dropout)
|
| 226 |
+
decoder_blocks.append(decoder_block)
|
| 227 |
+
|
| 228 |
+
# Create the encoder and decoder
|
| 229 |
+
encoder = Encoder(d_model, nn.ModuleList(encoder_blocks))
|
| 230 |
+
decoder = Decoder(d_model, nn.ModuleList(decoder_blocks))
|
| 231 |
+
|
| 232 |
+
# Create the projection layer
|
| 233 |
+
projection = Output(d_model, trg_vocab_size)
|
| 234 |
+
|
| 235 |
+
# Create the transformer
|
| 236 |
+
transformer = Transformer(encoder, decoder, src_embed, trg_embed, src_pos, trg_pos, projection)
|
| 237 |
+
|
| 238 |
+
# Initialize parameters
|
| 239 |
+
for p in transformer.parameters():
|
| 240 |
+
if p.dim() > 1:
|
| 241 |
+
nn.init.xavier_uniform_(p)
|
| 242 |
+
|
| 243 |
return transformer
|