51 lines
1.7 KiB
Python
51 lines
1.7 KiB
Python
import torch
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import torch.nn as nn
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import torch.nn.functional as F
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class DecoderLayer(nn.Module):
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def __init__(self, self_attention, cross_attention, d_model, d_ff=None,
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dropout=0.1, activation="relu"):
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super(DecoderLayer, self).__init__()
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d_ff = d_ff or 4*d_model
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self.self_attention = self_attention
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self.cross_attention = cross_attention
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self.conv1 = nn.Conv1d(in_channels=d_model, out_channels=d_ff, kernel_size=1)
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self.conv2 = nn.Conv1d(in_channels=d_ff, out_channels=d_model, kernel_size=1)
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self.norm1 = nn.LayerNorm(d_model)
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self.norm2 = nn.LayerNorm(d_model)
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self.norm3 = nn.LayerNorm(d_model)
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self.dropout = nn.Dropout(dropout)
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self.activation = F.relu if activation == "relu" else F.gelu
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def forward(self, x, cross, x_mask=None, cross_mask=None):
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x = x + self.dropout(self.self_attention(
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x, x, x,
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attn_mask=x_mask
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)[0])
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x = self.norm1(x)
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x = x + self.dropout(self.cross_attention(
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x, cross, cross,
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attn_mask=cross_mask
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)[0])
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y = x = self.norm2(x)
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y = self.dropout(self.activation(self.conv1(y.transpose(-1,1))))
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y = self.dropout(self.conv2(y).transpose(-1,1))
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return self.norm3(x+y)
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class Decoder(nn.Module):
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def __init__(self, layers, norm_layer=None):
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super(Decoder, self).__init__()
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self.layers = nn.ModuleList(layers)
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self.norm = norm_layer
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def forward(self, x, cross, x_mask=None, cross_mask=None):
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for layer in self.layers:
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x = layer(x, cross, x_mask=x_mask, cross_mask=cross_mask)
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if self.norm is not None:
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x = self.norm(x)
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return x |