torch.nn.utils.rnn.unpad_sequence

torch.nn.utils.rnn.unpad_sequence(padded_sequences, lengths, batch_first=False)

将填充张量解填充为可变长度张量列表。

unpad_sequence 将填充张量解堆叠为可变长度张量列表。

示例

>>> from torch.nn.utils.rnn import pad_sequence, unpad_sequence
>>> a = torch.ones(25, 300)
>>> b = torch.ones(22, 300)
>>> c = torch.ones(15, 300)
>>> sequences = [a, b, c]
>>> padded_sequences = pad_sequence(sequences)
>>> lengths = torch.as_tensor([v.size(0) for v in sequences])
>>> unpadded_sequences = unpad_sequence(padded_sequences, lengths)
>>> torch.allclose(sequences[0], unpadded_sequences[0])
True
>>> torch.allclose(sequences[1], unpadded_sequences[1])
True
>>> torch.allclose(sequences[2], unpadded_sequences[2])
True

参数

• padded_sequences (Tensor) – 填充序列。

• lengths (Tensor) – 原始（未填充）序列的长度。

• batch_first (bool, 可选) – 批次维度是否在前。默认值：False。

返回值

Tensor 对象的列表

返回类型

List[Tensor]