# PackedSequence

Source: https://www.tensorplay.cn/docs/generated/tensorplay.nn.utils.rnn.PackedSequence.html

```python
class tensorplay.nn.utils.rnn.PackedSequence(data, batch_sizes=None, sorted_indices=None, unsorted_indices=None)
```

Holds the data and list of [batch_sizes](#tensorplay.nn.utils.rnn.PackedSequence.batch_sizes) of a packed sequence.

All RNN modules accept packed sequences as inputs.

> **Note**
>
> Instances of this class should never be created manually. They are meant to be instantiated by functions like pack_padded_sequence(). Batch sizes represent the number elements at each sequence step in the batch, not the varying sequence lengths passed to pack_padded_sequence(). For instance, given data abc and x the PackedSequence would contain data axbc with batch_sizes=[2,1,1].

Variables:

- data ([Tensor](/docs/generated/tensorplay.Tensor.html#tensorplay.Tensor)) – Tensor containing packed sequence

- batch_sizes ([Tensor](/docs/generated/tensorplay.Tensor.html#tensorplay.Tensor)) – Tensor of integers holding information about the batch size at each sequence step

- sorted_indices ([Tensor](/docs/generated/tensorplay.Tensor.html#tensorplay.Tensor), optional) – Tensor of integers holding how this [PackedSequence](#tensorplay.nn.utils.rnn.PackedSequence) is constructed from sequences.

- unsorted_indices ([Tensor](/docs/generated/tensorplay.Tensor.html#tensorplay.Tensor), optional) – Tensor of integers holding how this to recover the original sequences with correct order.

> **Note**
>
> data can be on arbitrary device and of arbitrary dtype. sorted_indices and unsorted_indices must be int64 tensors on the same device as data. However, batch_sizes should always be a CPU int64 tensor. This invariant is maintained throughout PackedSequence class, and all functions that construct a PackedSequence in TensorPlay (i.e. they only pass in tensors conforming to this constraint).

```python
batch_sizes: Tensor
```

Alias for field number 1

```python
count(value, /)
```

Return number of occurrences of value.

```python
data: Tensor
```

Alias for field number 0

```python
index(value, start=0, stop=9223372036854775807, /)
```

Return first index of value.

Raises ValueError if the value is not present.

```python
property is_cuda: bool
```

Return true if self.data stored on a gpu.

```python
is_pinned() → bool
```

Return true if self.data stored on in pinned memory.

```python
sorted_indices: Tensor | None
```

Alias for field number 2

```python
to(*args: Any, **kwargs: Any)
```

Perform dtype and/or device conversion on self.data.

It has similar signature as tensorplay.Tensor.to()

> **Note**
>
> If the self.data Tensor already has the correct tensorplay.DType and tensorplay.Device, then self is returned. Otherwise, returns a copy with the desired configuration.

```python
unsorted_indices: Tensor | None
```

Alias for field number 3