python - pytorch/torchtext 中的单热编码

Question

我有一个来自 torchtext 的 Bucketiterator，我将它提供给 pytorch 中的模型。如何构造迭代器的示例:

train_iter, val_iter = BucketIterator.splits((train,val),
                                             batch_size=batch_size,
                                             sort_within_batch = True, 
                                             device = device, 
                                             shuffle=True, 
                                             sort_key=lambda x: (len(x.src), len(x.trg)))

然后将数据提供给这样的模型，我在其中使用 nn.Embedding 层。

class encoder(nn.Module):
    def __init__(self, input_dim, emb_dim, hid_dim, n_layers, dropout):
        super().__init__()

        self.input_dim = input_dim
        self.emb_dim = emb_dim
        self.hid_dim = hid_dim
        self.n_layers = n_layers
        self.dropout = dropout

        self.embedding = nn.Embedding(input_dim, emb_dim)

        self.rnn = nn.LSTM(emb_dim, hid_dim, n_layers, dropout = dropout)

        self.dropout = nn.Dropout(dropout)

    def forward(self, src):

        #src = [src sent len, batch size]

        embedded = self.dropout(self.embedding(src))

        #embedded = [src sent len, batch size, emb dim]
        hidden_enc = []
        outputs, hidden = self.rnn(embedded[0,:,:].unsqueeze(0))
        for i in range(1,len(embedded[:,1,1])):
            outputs, hidden = self.rnn(embedded[i,:,:].unsqueeze(0),hidden)
            hidden_cpu = []
            for k in range(len(hidden)):
                hidden_cpu.append(hidden[k])
                hidden_cpu[k] = hidden[k].cpu()
            hidden_enc.append(tuple(hidden_cpu))



        #outputs, hidden = self.rnn(embedded)

        #outputs = [src sent len, batch size, hid dim * n directions]
        #hidden = [n layers * n directions, batch size, hid dim]
        #cell = [n layers * n directions, batch size, hid dim]
        None
        #outputs are always from the top hidden layer

        return hidden, hidden_enc

但是如果我希望嵌入是单热编码的呢？我从事形式语言的工作，最好能保持标记之间的正交性。 pytorch 或 torchtext 似乎没有执行此操作的任何功能。

Answer 1

def get_one_hot_torch_tensor(in_tensor):"""函数将 1d 或 2d torch 张量转换为单热编码"""

n_channels = torch.max(in_tensor)+1  # maximum number of channels
if in_tensor.ndim == 2:
    out_one_hot = torch.zeros((n_channels, in_tensor.shape[0], in_tensor.shape[1]))
    # print(out_one_hot)
    index = np.indices((in_tensor.shape[0], in_tensor.shape[1]))  # create an array of indices
    x, y = index[0], index[1]
    print(x, y)

    out_one_hot[in_tensor, x, y] = 1
    print(out_one_hot)