# Dataset

Source: https://www.tensorplay.cn/docs/generated/tensorplay.utils.data.Dataset.html

```python
class tensorplay.utils.data.Dataset
```

An abstract class representing a [Dataset](#tensorplay.utils.data.Dataset).

All datasets that represent a map from keys to data samples should subclass
it. All subclasses should overwrite __getitem__(), supporting fetching
a data sample for a given key. Subclasses could also optionally overwrite
__len__(), which is expected to return the size of the dataset by many
[Sampler](/docs/generated/tensorplay.utils.data.Sampler.html#tensorplay.utils.data.Sampler) implementations and the default
options of [DataLoader](/docs/generated/tensorplay.utils.data.DataLoader.html#tensorplay.utils.data.DataLoader).

> **Note**
>
> DataLoader by default constructs an index sampler that yields integral indices. To make it work with a map-style dataset with non-integral indices/keys, a custom sampler must be provided.