real-jiakai/github-issues huggingface dataset:
wrong return type for `IterableDataset.shard()`
Author: ysngshn
State: open

### Describe the bug

`IterableDataset.shard()` has the wrong typing for its return as `"Dataset"`. It should be `"IterableDataset"`. Makes my IDE unhappy.

### Steps to reproduce the bug

look at [the source code](https://github.com/huggingface/datasets/blob/main/src/datasets/iterable_dataset.py#L2668)?

### Expected behavior

Correct return type as `"IterableDataset"`

### Environment info

datasets==3.1.0
Updated inconsistent output in documentation examples for `ClassLabel`
Author: sergiopaniego
State: open

fix #7129 

@stevhliu

Updated! 😄 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7293). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

@lhoestq, can you help with this failing test please? 🙏
Why return_tensors='pt' doesn't work？
Author: bw-wang19
State: open

### Describe the bug

I tried to add input_ids to dataset with map(), and I used the return_tensors='pt', but why I got the callback with the type of List？
![image](https://github.com/user-attachments/assets/ab046e20-2174-4e91-9cd6-4a296a43e83c)


### Steps to reproduce the bug

![image](https://github.com/user-attachments/assets/5d504d4c-22c7-4742-99a1-9cab78739b17)

### Expected behavior

Sorry for this silly question, I'm noob on using this tool. But I think it should return a tensor value as I have used the protocol？
When I tokenize only one sentence using tokenized_input=tokenizer(input, return_tensors='pt' )，it does return in tensor type. Why doesn't it work in map()？

### Environment info

transformers>=4.41.2,<=4.45.0
datasets>=2.16.0,<=2.21.0
accelerate>=0.30.1,<=0.34.2
peft>=0.11.1,<=0.12.0
trl>=0.8.6,<=0.9.6
gradio>=4.0.0
pandas>=2.0.0
scipy
einops
sentencepiece
tiktoken
protobuf
uvicorn
pydantic
fastapi
sse-starlette
matplotlib>=3.7.0
fire
packaging
pyyaml
numpy<2.0.0


Hi ! `datasets` uses Arrow as storage backend which is agnostic to deep learning frameworks like torch. If you want to get torch tensors back, you need to do `dataset = dataset.with_format("torch")`

> Hi ! `datasets` uses Arrow as storage backend which is agnostic to deep learning frameworks like torch. If you want to get torch tensors back, you need to do `dataset = dataset.with_format("torch")`

It does work! Thanks for your suggestion!
`Dataset.save_to_disk` hangs when using num_proc > 1
Author: JohannesAck
State: open

### Describe the bug

Hi, I'm encountered a small issue when saving datasets that led to the saving taking up to multiple hours.
Specifically, [`Dataset.save_to_disk`](https://huggingface.co/docs/datasets/main/en/package_reference/main_classes#datasets.Dataset.save_to_disk) is a lot slower when using `num_proc>1` than when using `num_proc=1`

The documentation mentions that "Multiprocessing is disabled by default.", but there is no explanation on how to enable it.

### Steps to reproduce the bug

```
import numpy as np
from datasets import Dataset

n_samples = int(4e6)
n_tokens_sample = 100
data_dict = {
    'tokens' : np.random.randint(0, 100, (n_samples, n_tokens_sample)),
}

dataset = Dataset.from_dict(data_dict)
dataset.save_to_disk('test_dataset', num_proc=1)
dataset.save_to_disk('test_dataset', num_proc=4)
dataset.save_to_disk('test_dataset', num_proc=8)
```

This results in:
```
>>> dataset.save_to_disk('test_dataset', num_proc=1)
Saving the dataset (7/7 shards): 100%|██████████████| 4000000/4000000 [00:17<00:00, 228075.15 examples/s]
>>> dataset.save_to_disk('test_dataset', num_proc=4)
Saving the dataset (7/7 shards): 100%|██████████████| 4000000/4000000 [01:49<00:00, 36583.75 examples/s]
>>> dataset.save_to_disk('test_dataset', num_proc=8)
Saving the dataset (8/8 shards): 100%|██████████████| 4000000/4000000 [02:11<00:00, 30518.43 examples/s]
```

With larger datasets it can take hours, but I didn't benchmark that for this bug report.

### Expected behavior

I would expect using `num_proc>1` to be faster instead of slower than `num_proc=1`. 

### Environment info

- `datasets` version: 3.1.0
- Platform: Linux-5.15.153.1-microsoft-standard-WSL2-x86_64-with-glibc2.35
- Python version: 3.10.12
- `huggingface_hub` version: 0.26.2
- PyArrow version: 18.0.0
- Pandas version: 2.2.3
- `fsspec` version: 2024.6.1
Support for identifier-based automated split construction
Author: alex-hh
State: open

### Feature request

As far as I understand, automated construction of splits for hub datasets is currently based on either file names or directory structure ([as described here](https://huggingface.co/docs/datasets/en/repository_structure))

It would seem to be pretty useful to also allow splits to be based on identifiers of individual examples

This could be configured like 
{"split_name": {"column_name": [column values in split]}}

(This in turn requires unique 'index' columns, which could be explicitly supported or just assumed to be defined appropriately by the user).

I guess a potential downside would be that shards would end up spanning different splits - is this something that can be handled somehow? Would this only affect streaming from hub?

### Motivation

The main motivation would be that all data files could be stored in a single directory, and multiple sets of splits could be generated from the same data. This is often useful for large datasets with multiple distinct sets of splits.

This could all be configured via the README.md yaml configs

### Your contribution

May be able to contribute if it seems like a good idea

Hi ! You can already configure the README.md to have multiple sets of splits, e.g.

```yaml
configs:
- config_name: my_first_set_of_split
  data_files:
  - split: train
    path: *.csv
- config_name: my_second_set_of_split
  data_files:
  - split: train
    path: train-*.csv
  - split: test
    path: test-*.csv
```

Hi - I had something slightly different in mind:

Currently the yaml splits specified like this only allow specifying which filenames to pass to each split.
But what if I have a situation where I know which individual *training examples* I want to put in each split.

I could build split-specific files, however for large datasets with overlapping (e.g. multiple sets of) splits this could result in significant duplication of data.

I can see that this could actually be very much intended (i.e. to discourage overlapping splits), but wondered whether some support for handling splits based on individual identifiers is something that could be considered. 

This is not supported right now :/ Though you can load the data in two steps like this
```python
from datasets import load_dataset

full_dataset = load_dataset("username/dataset", split="train")
my_first_set_indices = load_dataset("username/dataset", "my_first_set_of_split", split="train")

my_first_set = full_dataset.select(my_first_set_indices["indices"])
```

you can create such a dataset by adapting this code for example
```python
# upload the full dataset
full_dataset.push_to_hub("username/dataset")
# then upload the indices for each set
DatasetDict({
    "train": Dataset.from_dict({"indices": [0, 1, 2, 3]}),
    "test": Dataset.from_dict({"indices": [4, 5]}),
}).push_to_hub("username/dataset", "my_first_set_of_split")
Concurrent loading in `load_from_disk` - `num_proc` as a param 
Author: unography
State: closed

### Feature request

https://github.com/huggingface/datasets/pull/6464 mentions a `num_proc` param while loading dataset from disk, but can't find that in the documentation and code anywhere

### Motivation

Make loading large datasets from disk faster

### Your contribution

Happy to contribute if given pointers
support for custom feature encoding/decoding
Author: alex-hh
State: closed

Fix for https://github.com/huggingface/datasets/issues/7220 as suggested in discussion, in preference to #7221 

(only concern would be on effect on type checking with custom feature types that aren't covered by FeatureType?)

@lhoestq 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7284). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
File not found error
Author: MichielBontenbal
State: open

### Describe the bug

I get a FileNotFoundError:
<img width="944" alt="image" src="https://github.com/user-attachments/assets/1336bc08-06f6-4682-a3c0-071ff65efa87">


### Steps to reproduce the bug

See screenshot.



### Expected behavior

I want to load one audiofile from the dataset. 

### Environment info

MacOs Intel 14.6.1 (23G93)
Python 3.10.9
Numpy 1.23
Datasets latest version

Link to the dataset: https://huggingface.co/datasets/MichielBontenbal/UrbanSounds
Add filename in error message when ReadError or similar occur
Author: elisa-aleman
State: open

Please update error messages to include relevant information for debugging when loading datasets with `load_dataset()` that may have a few corrupted files. 

Whenever downloading a full dataset, some files might be corrupted (either at the source or from downloading corruption). 

However the errors often only let me know it was a tar file if `tarfile.ReadError` appears on the traceback, and I imagine similarly for other file types. 

This makes it really hard to debug which file is corrupted, and when dealing with very large datasets, it shouldn't be necessary to force download everything again.

Hi Elisa, please share the error traceback here, and if you manage to find the location in the `datasets` code where the error occurs, feel free to open a PR to add the necessary logging / improve the error message.

> please share the error traceback

I don't have access to it but it should be during [this exception](https://github.com/huggingface/datasets/blob/2049c00921c59cdeb835137a1c49639cf175af07/src/datasets/builder.py#L1643) which happens during the loading of a dataset. If one of the downloaded files is corrupted, the for loop will not yield correctly, and the error will come from, say, in the case of tar files, [this iterable](https://github.com/huggingface/datasets/blob/2049c00921c59cdeb835137a1c49639cf175af07/src/datasets/utils/file_utils.py#L1293) which has no explicit error handling that leaves clues as to which file has failed.

I only know the case for tar files, but I consider this issue could be happening across different file types too.

I think having a better error handling for this tar iterable would be useful already, maybe a simple try/except in `_iter_from_urlpath` that checks for `tarfile.ReadError` and raises an error with the `urlpath` mentioned in the error ?

I think not just from higher calls like the `_iter_from_urlpath` but directly wherever a file is attempted to be opened would be the best case, as the traceback would simply lead to that.

so maybe there should be better error messages in each dataset builder definition ? e.g. in https://github.com/huggingface/datasets/blob/main/src/datasets/packaged_modules/webdataset/webdataset.py for webdataset TAR archives
Add link to video dataset
Author: NielsRogge
State: closed

This PR updates https://huggingface.co/docs/datasets/loading to also link to the new video loading docs.

cc @mfarre 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7277). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
Raise error for incorrect JSON serialization
Author: varadhbhatnagar
State: closed

Raise error when `lines = False` and `batch_size < Dataset.num_rows` in `Dataset.to_json()`.

Issue: #7037 

Related PRs:
#7039 #7181 

PTAL @lhoestq @albertvillanova 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7273). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
Memory leak when streaming
Author: Jourdelune
State: open

### Describe the bug

I try to use a dataset with streaming=True, the issue I have is that the RAM usage becomes higher and higher until it is no longer sustainable.

I understand that huggingface store data in ram during the streaming, and more worker in dataloader there are, more a lot of shard will be stored in ram, but the issue I have is that the ram usage is not constant. So after each new shard loaded, the ram usage will be higher and higher.

### Steps to reproduce the bug

You can run this code and see you ram usage, after each shard of 255 examples, your ram usage will be extended.
```py
from datasets import load_dataset
from torch.utils.data import DataLoader

dataset = load_dataset("WaveGenAI/dataset", streaming=True)

dataloader = DataLoader(dataset["train"], num_workers=3)

for i, data in enumerate(dataloader):
    print(i, end="\r")
```

### Expected behavior

The Ram usage should be always the same (just 3 shards loaded in the ram).

### Environment info

- `datasets` version: 3.0.1
- Platform: Linux-6.10.5-arch1-1-x86_64-with-glibc2.40
- Python version: 3.12.4
- `huggingface_hub` version: 0.26.0
- PyArrow version: 17.0.0
- Pandas version: 2.2.3
- `fsspec` version: 2024.6.1

I seem to have encountered the same problem when loading non streaming datasets. load_from_disk. Causing hundreds of GB of memory, but the dataset actually only has 50GB

FYI when streaming parquet data, only one row group per worker is loaded in memory at a time.

Btw for datasets of embeddings you can surely optimize your RAM by reading the data as torch tensors directly instead of the default python lists

```python
from datasets import load_dataset
from torch.utils.data import DataLoader

dataset = load_dataset("WaveGenAI/dataset", streaming=True).with_format("torch")

dataloader = DataLoader(dataset["train"], num_workers=3)
```
load_from_disk
Author: ghaith-mq
State: open

### Describe the bug

I have data saved with save_to_disk. The data is big (700Gb). When I try loading it, the only option is load_from_disk, and this function copies the data to a tmp directory, causing me to run out of disk space. Is there an alternative solution to that?

### Steps to reproduce the bug

when trying to load data using load_From_disk after being saved using save_to_disk 

### Expected behavior

run out of disk space

### Environment info

lateest version

Hello, It's an interesting issue here. I have the same problem, I have a local dataset and I want to push the dataset to the hub but huggingface does a copy of it.

```py
from datasets import load_dataset

dataset = load_dataset("webdataset", data_files="/media/works/data/*.tar") # copy here
dataset.push_to_hub("WaveGenAI/audios2")
```

Edit: I can use HfApi for my use case
Source installation fails on Macintosh with python 3.10
Author: mayankagarwals
State: open

### Describe the bug

Hi, 

Decord is a dev dependency not maintained since couple years. 
It does not have an ARM package available rendering it uninstallable on non-intel based macs 

Suggestion is to move to eva-decord (https://github.com/georgia-tech-db/eva-decord)  which doesnt have this problem. 

Happy to raise a PR


### Steps to reproduce the bug

Source installation as mentioned in contributinog.md

### Expected behavior

Installation without decord failing to be installed.

### Environment info

python=3.10, M3 Mac 

I encountered the same problem on M1, a workaround I did was to simply comment out the dependency:

```python
...
    "zstandard",
    "polars[timezone]>=0.20.0",
    # "decord==0.6.0",
]
```

This worked for me as the adjustments I did to the code do not use the dependency, but I do not know if the same holds for you.

I also do not think it is a good idea to rely on a dependency (I mean decord) that has not been maintained for 2 years, but I saw that even eva-decord hasn't been maintained since last year.

Did you get it to work with eva-decord?
The dataset viewer should be available soon. Please retry later.
Author: viiika
State: closed

### Describe the bug

After waiting for 2 hours, it still presents ``The dataset viewer should be available soon. Please retry later.''

### Steps to reproduce the bug

dataset link: https://huggingface.co/datasets/BryanW/HI_EDIT

### Expected behavior

Present the dataset viewer.

### Environment info

NA

Waiting is all you need. 10 hours later, it works.
Allow video with disabeld decoding without decord
Author: lhoestq
State: closed

for the viewer, this way it can use Video(decode=False) and doesn't need decord (which causes segfaults)

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7262). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
Cannot load the cache when mapping the dataset
Author: zhangn77
State: open

### Describe the bug

I'm training the flux controlnet. The train_dataset.map() takes long time to finish. However, when I killed one training process and want to restart a new training with the same dataset. I can't reuse the mapped result even I defined the cache dir for the dataset.

with accelerator.main_process_first():
        from datasets.fingerprint import Hasher

        # fingerprint used by the cache for the other processes to load the result
        # details: https://github.com/huggingface/diffusers/pull/4038#discussion_r1266078401
        new_fingerprint = Hasher.hash(args)
        train_dataset = train_dataset.map(
            compute_embeddings_fn, batched=True, new_fingerprint=new_fingerprint, batch_size=10,
        )

### Steps to reproduce the bug

train flux controlnet and start again



### Expected behavior

will not map again

### Environment info

latest diffusers
cache can't cleaned or disabled
Author: charliedream1
State: open

### Describe the bug

I tried following ways, the cache can't be disabled. 

I got 2T data, but I also got more than 2T cache file. I got pressure on storage. I need to diable cache or cleaned immediately after processed. Following ways are all not working, please give some help!

```python
from datasets import disable_caching
from transformers import AutoTokenizer
disable_caching()

tokenizer = AutoTokenizer.from_pretrained(args.tokenizer_path)
def tokenization_fn(examples):
    column_name = 'text' if 'text' in examples else 'data'
    tokenized_inputs = tokenizer(
        examples[column_name], return_special_tokens_mask=True, truncation=False,
        max_length=tokenizer.model_max_length
    )
    return tokenized_inputs

data = load_dataset('json', data_files=save_local_path, split='train', cache_dir=None)
data.cleanup_cache_files()
updated_dataset = data.map(tokenization_fn, load_from_cache_file=False)
updated_dataset .cleanup_cache_files()
```

### Expected behavior

no cache file generated

### Environment info

Ubuntu 20.04.6 LTS
datasets  3.0.2
Don't embed videos
Author: lhoestq
State: closed

don't include video bytes when running download_and_prepare(format="parquet")

this also affects push_to_hub which will just upload the local paths of the videos though

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7259). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
fix decord import
Author: lhoestq
State: closed

delay the import until Video() is instantiated + also import duckdb first (otherwise importing duckdb later causes a segfault)

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7255). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
mismatch for datatypes when providing `Features` with `Array2D` and user specified `dtype` and using with_format("numpy")
Author: Akhil-CM
State: open

### Describe the bug

If the user provides a `Features` type value to `datasets.Dataset` with members having `Array2D` with a value for `dtype`, it is not respected during `with_format("numpy")` which should return a `np.array` with `dtype` that the user provided for `Array2D`. It seems for floats, it will be set to `float32` and for ints it will be set to `int64`

### Steps to reproduce the bug

```python
import numpy as np
import datasets
from datasets import Dataset, Features, Array2D

print(f"datasets version: {datasets.__version__}")

data_info = {
    "arr_float" : "float64",
    "arr_int" : "int32"
}

sample = {key : [np.zeros([4, 5], dtype=dtype)] for key, dtype in data_info.items()}

features = {key : Array2D(shape=(None, 5), dtype=dtype) for key, dtype in data_info.items()}
features = Features(features)

dataset = Dataset.from_dict(sample, features=features)

ds = dataset.with_format("numpy")
for key in features:
    print(f"{key} feature dtype: ", ds.features[key].dtype)
    print(f"{key} dtype:", ds[key].dtype)
```

Output:
```bash
datasets version: 3.0.2
arr_float feature dtype:  float64
arr_float dtype: float32
arr_int feature dtype:  int32
arr_int dtype: int64
```

### Expected behavior

It should return a `np.array` with `dtype` that the user provided for the corresponding member in the `Features` type value

### Environment info

- `datasets` version: 3.0.2
- Platform: Linux-6.11.5-arch1-1-x86_64-with-glibc2.40
- Python version: 3.12.7
- `huggingface_hub` version: 0.26.1
- PyArrow version: 16.1.0
- Pandas version: 2.2.2
- `fsspec` version: 2024.5.0

It seems that https://github.com/huggingface/datasets/issues/5517 is exactly the same issue.

It was mentioned there that this would be fixed in version 3.x
Add IterableDataset.shard()
Author: lhoestq
State: closed

Will be useful to distribute a dataset across workers (other than pytorch) like spark

I also renamed `.n_shards` -> `.num_shards` for consistency and kept the old name for backward compatibility. And a few changes in internal functions for consistency as well (rank, world_size -> num_shards, index)

Breaking change: the new default for `contiguous` in `Dataset.shard()` is `True`, but imo not a big deal since I couldn't find any usage of `contiguous=False` internally (we always do contiguous=True for map-style datasets since its more optimized) or in the wild

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7252). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
Basic XML support (mostly copy pasted from text)
Author: lhoestq
State: closed

enable the viewer for datasets like https://huggingface.co/datasets/FrancophonIA/e-calm (there will be more and more apparently)


The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7250). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
use huggingface_hub offline mode
Author: lhoestq
State: closed

and better handling of LocalEntryNotfoundError cc @Wauplin 

follow up to #7234 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7244). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
ArrayXD with None as leading dim incompatible with DatasetCardData
Author: alex-hh
State: open

### Describe the bug

Creating a dataset with ArrayXD features leads to errors when downloading from hub due to DatasetCardData removing the Nones

@lhoestq 

### Steps to reproduce the bug

```python
import numpy as np
from datasets import Array2D, Dataset, Features, load_dataset

def examples_generator():
    for i in range(4):
        yield {
            "array_1d": np.zeros((10,1), dtype="uint16"),
            "array_2d": np.zeros((10, 1), dtype="uint16"),
        }

features = Features(array_1d=Array2D((None,1), "uint16"), array_2d=Array2D((None, 1), "uint16"))
dataset = Dataset.from_generator(examples_generator, features=features)
dataset.push_to_hub("alex-hh/test_array_1d2d")
ds = load_dataset("alex-hh/test_array_1d2d")
```

Source of error appears to be DatasetCardData.to_dict invoking DatasetCardData._remove_none
```python
from huggingface_hub import DatasetCardData
from datasets.info import DatasetInfosDict

dataset_card_data = DatasetCardData()
DatasetInfosDict({"default": dataset.info.copy()}).to_dataset_card_data(dataset_card_data)
print(dataset_card_data.to_dict())  # removes Nones in shape
```

### Expected behavior

Should be possible to load datasets saved with shape None in leading dimension

### Environment info

3.0.2 and latest huggingface_hub

It looks like `CardData` in `huggingface_hub` removes None values where it shouldn't. Indeed it calls `_remove_none` on the return of `to_dict()`:

```python
    def to_dict(self) -> Dict[str, Any]:
        """Converts CardData to a dict.

        Returns:
            `dict`: CardData represented as a dictionary ready to be dumped to a YAML
            block for inclusion in a README.md file.
        """

        data_dict = copy.deepcopy(self.__dict__)
        self._to_dict(data_dict)
        return _remove_none(data_dict)
```

Would it be ok to remove `list()` from being scanned in `_remove_none` ? it could also be a specific behavior to DatasetCardData if necessary @Wauplin 

I have actually no idea why none values are removed in model and dataset card data... :see_no_evil:
Looks like `_remove_none` has been introduced at the same time as the entire repocard module (see https://github.com/huggingface/huggingface_hub/pull/940). I would be tempted to remove `_remove_none` entirely actually and only remove "top-level" None values (i.e. if something like `pipeline_tag=None` due to a default value in kwargs => we remove it). Hard to tell what could be the side effects but I'm not against trying.


However, I'm not really in favor in making an exception only for lists. It would mean that tuples, sets and dicts are filtered but not lists, which is pretty inconsistent.

let's do it for top level attributes yes

I opened https://github.com/huggingface/huggingface_hub/pull/2626 to address it :)

thanks !
`push_to_hub` overwrite argument
Author: ceferisbarov
State: closed

### Feature request

Add an `overwrite` argument to the `push_to_hub` method.

### Motivation

I want to overwrite a repo without deleting it on Hugging Face. Is this possible? I couldn't find anything in the documentation or tutorials.

### Your contribution

I can create a PR.

Hi ! Do you mean deleting all the files ? or erasing the repository git history before push_to_hub ?

Hi! I meant the latter.

I don't think there is a `huggingface_hub` utility to erase the git history, cc @Wauplin maybe ?

What is the goal exactly of deleting all the git history without deleting the repo? 

You can use [`super_squash_commit`](https://huggingface.co/docs/huggingface_hub/main/en/package_reference/hf_api#huggingface_hub.HfApi.super_squash_history) to squash all the commits into a single one, hence deleting the git history. This is not exactly what you asked for since it squashes the commits for a specific revision (example: "all commits on main"). This means that if other branches exists, they are kept the same. Also if some PRs are already opened on the repo, they will become unmergeable since the commits will have diverted.

So the solution is:

```python
from huggingface_hub import HfApi
repo_id = "username/dataset_name"
ds.push_to_hub(repo_id)
HfApi().super_squash_commit(repo_id)
```

This way you erase previous git history to end up with only 1 commit containing your dataset.
Still, I'd be curious why it's important in your case. Is it to save storage space ? or to disallow loading old versions of the data ?

Thanks, everyone! I am building a new dataset and playing around with column names, splits, etc. Sometimes I push to the hub to share it with other teammates, I don't want those variations to be part of the repo. Deleting the repo from the website takes a little time, but it also loses repo settings that I have set, since I always set it to public with manually approved requests.

BTW, I had to write `HfApi().super_squash_history(repo_id, repo_type="dataset")`, but otherwise it works.

@ceferisbarov just to let you know, recreating a gated repo + granting access to your teammates is something that you can automate with something like this (not fully tested but should work):

```py
from huggingface_hub import HfApi

api = HfApi()
api.delete_repo(repo_id, repo_type="dataset", missing_ok=True)
api.create_repo(repo_id, repo_type="dataset", private=False)
api.update_repo_settings(repo_id, repo_type="dataset", gated="manual")
for user in ["user1", "user2"]  # list of teammates
    api.grant_access(repo_id, user, repo_type="dataset")
```

I think it'd be a better solution than squashing commits (which is more of a hack), typically if you are using the dataset viewer.

This is great, @Wauplin. If we can achieve this with HfApi, then we probably don't need to add another parameter to push_to_hub. I am closing the issue.
Feature Request: Add functionality to pass split types like train, test in DatasetDict.map
Author: jp1924
State: open

Hello datasets!

We often encounter situations where we need to preprocess data differently depending on split types such as train, valid, and test. 

However, while DatasetDict.map has features to pass rank or index, there's no functionality to pass split types. 
Therefore, I propose adding a 'with_splits' parameter to DatasetDict, which would allow passing the split type through fn_kwargs.
incompatibily issue when using load_dataset with datasets==3.0.1
Author: jupiterMJM
State: open

### Describe the bug

There is a bug when using load_dataset with dataset version at 3.0.1 .
Please see below in the "steps to reproduce the bug".
To resolve the bug, I had to downgrade to version 2.21.0
OS: Ubuntu 24 (AWS instance)
Python: same bug under 3.12 and 3.10


The error I had was:
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/ubuntu/miniconda3/envs/maxence_env/lib/python3.10/site-packages/datasets/load.py", line 2096, in load_dataset
    builder_instance.download_and_prepare(
  File "/home/ubuntu/miniconda3/envs/maxence_env/lib/python3.10/site-packages/datasets/builder.py", line 924, in download_and_prepare
    self._download_and_prepare(
  File "/home/ubuntu/miniconda3/envs/maxence_env/lib/python3.10/site-packages/datasets/builder.py", line 1647, in _download_and_prepare
    super()._download_and_prepare(
  File "/home/ubuntu/miniconda3/envs/maxence_env/lib/python3.10/site-packages/datasets/builder.py", line 977, in _download_and_prepare
    split_generators = self._split_generators(dl_manager, **split_generators_kwargs)
  File "/home/ubuntu/.cache/huggingface/modules/datasets_modules/datasets/mozilla-foundation--common_voice_6_0/cb17afd34f5799f97e8f48398748f83006335b702bd785f9880797838d541b81/common_voice_6_0.py", line 159, in _split_generators
    archive_path = dl_manager.download(self._get_bundle_url(self.config.name, bundle_url_template))
  File "/home/ubuntu/miniconda3/envs/maxence_env/lib/python3.10/site-packages/datasets/download/download_manager.py", line 150, in download
    download_config = self.download_config.copy()
  File "/home/ubuntu/miniconda3/envs/maxence_env/lib/python3.10/site-packages/datasets/download/download_config.py", line 73, in copy
    return self.__class__(**{k: copy.deepcopy(v) for k, v in self.__dict__.items()})
TypeError: DownloadConfig.__init__() got an unexpected keyword argument 'ignore_url_params'

### Steps to reproduce the bug

1. install dataset with ```pip install datasets --upgrade```
2. launch python; from datasets import loaad_dataset
3. run load_dataset("mozilla-foundation/common_voice_6_0")
4. exit python
5. uninstall datasets; then ```pip install datasets==2.21.0```
6. launch python; from datasets import loaad_dataset
7. run load_dataset("mozilla-foundation/common_voice_6_0")
8. Everything runs great now

### Expected behavior

Be able to download a dataset without error

### Environment info

Copy-and-paste the text below in your GitHub issue.

- `datasets` version: 3.0.1
- Platform: Linux-6.8.0-1017-aws-x86_64-with-glibc2.39
- Python version: 3.12.4
- `huggingface_hub` version: 0.26.0
- PyArrow version: 17.0.0
- Pandas version: 2.2.3
- `fsspec` version: 2024.6.1
No need for dataset_info
Author: lhoestq
State: closed

save a useless call to /api/datasets/repo_id

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7234). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

merging this one for now, let me know if you'd like to see additional changes for error handling (I'll take care of them before doing a release)
Video support
Author: lhoestq
State: closed

(wip and experimental)

adding the `Video` type based on `VideoReader` from `decord`

```python
>>>from datasets import load_dataset
>>> ds = load_dataset("path/to/videos", split="train").with_format("torch")
>>> print(ds[0]["video"])
<decord.video_reader.VideoReader object at 0x337a47910>
>>> print(ds[0]["video"][0])
tensor([[[73, 73, 73],
         [73, 73, 73],
         [73, 73, 73],
         ...,
         [23, 23, 23],
         [23, 23, 23],
         [23, 23, 23]]], dtype=torch.uint8)
```

the storage is the same as for audio and images: `{"path": pa.string(), "bytes": pa.binary()}` and I did a small to keep the hf:// URL in the "path" field if possible, this way the viewer can link to fiels on the hub if possible

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7230). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.
Composite (multi-column) features
Author: alex-hh
State: open

### Feature request

Structured data types (graphs etc.) might often be most efficiently stored as multiple columns, which then need to be combined during feature decoding

Although it is currently possible to nest features as structs, my impression is that in particular when dealing with e.g. a feature composed of multiple numpy array / ArrayXD's, it would be more efficient to store each ArrayXD as a separate column (though I'm not sure by how much)

Perhaps specification / implementation could be supported by something like:

```
features=Features(**{("feature0", "feature1")=Features(feature0=Array2D((None,10), dtype="float32"), feature1=Array2D((None,10), dtype="float32"))
```

### Motivation

Defining efficient composite feature types based on numpy arrays for representing data such as graphs with multiple node and edge attributes is currently challenging.

### Your contribution

Possibly able to contribute
Add R as a How to use from the Polars (R) Library as an option
Author: ran-codes
State: open

### Feature request

The boiler plate code to access a dataset via the hugging face file system is very useful. Please addd 


## Add Polars (R) option
The equivailent code works, because the [Polars-R](https://github.com/pola-rs/r-polars) wrapper has hugging faces funcitonaliy as well.

```r
library(polars)

df <- pl$read_parquet("hf://datasets/SALURBAL/core__admin_cube_public/core__admin_cube_public.parquet")
```

## Polars (python) option
![image](https://github.com/user-attachments/assets/8f1bcd19-e578-4b18-b324-7cc00b80ac0a)


## Libraries Currently

![image](https://github.com/user-attachments/assets/0cf50063-f9db-443c-97b4-3ef0664b6e6e)




### Motivation

There are many data/analysis/research/statistics teams (particularly in academia and pharma) that use R as the default language. R has great integration with most of the newer data techs (arrow, parquet, polars) and having this included could really help in bringing this community into the hugging faces ecosystem.

**This is a small/low-hanging-fruit front end change but would make a big impact expanding the community**

### Your contribution

I am not sure which repositroy this should be in, but I have experience in R, Python and JS and happy to submit a PR in the appropriate repository.
add CustomFeature base class to support user-defined features with encoding/decoding logic
Author: alex-hh
State: open

intended as fix for #7220 if this kind of extensibility is something that datasets is willing to support!


```python
from datasets.features.features import CustomFeature


class ListOfStrs(CustomFeature):
    requires_encoding = True
    def _encode_example(self, value):
        if isinstance(value, str):
            return [str]
        else:
            return value
feats = Features(strlist=ListOfStrs())
feats.encode_example({"strlist": "a"})["strlist"] == feats["strlist"].encode_example("a")
```

@lhoestq would you be open to supporting this kind of extensibility?

I suggested a fix in https://github.com/huggingface/datasets/issues/7220 that would not necessarily require a parent class for custom features, lmk what you think
Custom features not compatible with special encoding/decoding logic
Author: alex-hh
State: open

### Describe the bug

It is possible to register custom features using datasets.features.features.register_feature (https://github.com/huggingface/datasets/pull/6727)

However such features are not compatible with Features.encode_example/decode_example if they require special encoding / decoding logic because encode_nested_example / decode_nested_example checks whether the feature is in a fixed list of encodable types:

https://github.com/huggingface/datasets/blob/16a121d7821a7691815a966270f577e2c503473f/src/datasets/features/features.py#L1349

This prevents the extensibility of features to complex cases

### Steps to reproduce the bug

```python
class ListOfStrs:
    def encode_example(self, value):
        if isinstance(value, str):
            return [str]
        else:
            return value
feats = Features(strlist=ListOfStrs())
assert feats.encode_example({"strlist": "a"})["strlist"] = feats["strlist"].encode_example("a")}
```

### Expected behavior

Registered feature types should be encoded based on some property of the feature (e.g. requires_encoding)?

### Environment info

3.0.2

I think you can fix this simply by replacing the line with hardcoded features with `hastattr(schema, "encode_example")` actually

#7284
ds.map(f, num_proc=10) is slower than df.apply
Author: lanlanlanlanlanlan365
State: open

### Describe the bug

pandas columns: song_id, song_name
ds = Dataset.from_pandas(df)

def has_cover(song_name):
    if song_name is None or pd.isna(song_name):
        return False
    return 'cover' in song_name.lower()

df['has_cover'] = df.song_name.progress_apply(has_cover)
ds = ds.map(lambda x: {'has_cover': has_cover(x['song_name'])}, num_proc=10)

time cost: 
1. df.apply: 100%|██████████| 12500592/12500592 [00:13<00:00, 959825.47it/s]
2. ds.map: Map (num_proc=10):  31%
 3899028/12500592 [00:28<00:38, 222532.89 examples/s]

### Steps to reproduce the bug

pandas columns: song_id, song_name
ds = Dataset.from_pandas(df)

def has_cover(song_name):
    if song_name is None or pd.isna(song_name):
        return False
    return 'cover' in song_name.lower()

df['has_cover'] = df.song_name.progress_apply(has_cover)
ds = ds.map(lambda x: {'has_cover': has_cover(x['song_name'])}, num_proc=10)

### Expected behavior

ds.map is ~num_proc faster than df.apply

### Environment info

pandas: 2.2.2
datasets: 2.19.1

Hi ! `map()` reads all the columns and writes the resulting dataset with all the columns as well, while df.column_name.apply only reads and writes one column and does it in memory. So this is speed difference is actually expected.

Moreover using multiprocessing on a dataset that lives in memory (from_pandas uses the same in-memory data as the pandas DataFrame while load_dataset or from_generator load from disk) requires to copy the data to each subprocess which can also be slow. Data loaded from disk don't need to be copied though since they work as a form of shared memory thanks to memory mapping.

However you can make you map() call much faster by making it read and write only the column you want:

```python
has_cover_ds = ds.map(lambda song_name: {'has_cover': has_cover(song_name)}, input_columns=["song_name"], remove_columns=ds.column_names)  # outputs a dataset with 1 column
ds = ds.concatenate_datasets([ds, has_cover_ds], axis=1)
```

and if your dataset is loaded from disk you can pass num_proc=10 and get a nice speed up as well (no need to copy the data to subprocesses)
Formatted map + with_format(None) changes array dtype for iterable datasets
Author: alex-hh
State: open

### Describe the bug

When applying with_format -> map -> with_format(None), array dtypes seem to change, even if features are passed 

### Steps to reproduce the bug

```python
features=Features(**{"array0": Array3D((None, 10, 10), dtype="float32")})
dataset = Dataset.from_dict({f"array0": [np.zeros((100,10,10), dtype=np.float32)]*25}, features=features)
ds = dataset.to_iterable_dataset().with_format("numpy").map(lambda x: x, features=features)
ex_0 = next(iter(ds))
ds = dataset.to_iterable_dataset().with_format("numpy").map(lambda x: x, features=features).with_format(None)
ex_1 = next(iter(ds))
assert ex_1["array0"].dtype == ex_0["array0"].dtype, f"{ex_1['array0'].dtype} {ex_0['array0'].dtype}"
```


### Expected behavior

Dtypes should be preserved.

### Environment info

3.0.2

possibly due to this logic:

```python
    def _arrow_array_to_numpy(self, pa_array: pa.Array) -> np.ndarray:
        if isinstance(pa_array, pa.ChunkedArray):
            if isinstance(pa_array.type, _ArrayXDExtensionType):
                # don't call to_pylist() to preserve dtype of the fixed-size array
                zero_copy_only = _is_zero_copy_only(pa_array.type.storage_dtype, unnest=True)
                array: List = [
                    row for chunk in pa_array.chunks for row in chunk.to_numpy(zero_copy_only=zero_copy_only)
                ]
            else:
                zero_copy_only = _is_zero_copy_only(pa_array.type) and all(
                    not _is_array_with_nulls(chunk) for chunk in pa_array.chunks
                )
                array: List = [
                    row for chunk in pa_array.chunks for row in chunk.to_numpy(zero_copy_only=zero_copy_only)
                ]
        else:
            if isinstance(pa_array.type, _ArrayXDExtensionType):
                # don't call to_pylist() to preserve dtype of the fixed-size array
                zero_copy_only = _is_zero_copy_only(pa_array.type.storage_dtype, unnest=True)
                array: List = pa_array.to_numpy(zero_copy_only=zero_copy_only)
            else:
                zero_copy_only = _is_zero_copy_only(pa_array.type) and not _is_array_with_nulls(pa_array)
                array: List = pa_array.to_numpy(zero_copy_only=zero_copy_only).tolist()
```
Add with_rank to Dataset.from_generator
Author: muthissar
State: open

### Feature request

Add `with_rank` to `Dataset.from_generator` similar to `Dataset.map` and `Dataset.filter`. 

### Motivation

As for `Dataset.map` and `Dataset.filter`, this is useful when creating cache files using multi-GPU, where the rank can be used to select GPU IDs. For now, rank can be added in the `gen_kwars` argument; however, this, in turn, includes the rank when computing the fingerprint.

### Your contribution

Added #7199 which passes rank based on the `job_id` set by `num_proc`.
Describe only selected fields in README
Author: alozowski
State: open

### Feature request

Hi Datasets team! 

Is it possible to add the ability to describe only selected fields of the dataset files in `README.md`? For example, I have this open dataset ([open-llm-leaderboard/results](https://huggingface.co/datasets/open-llm-leaderboard/results?row=0)) and I want to describe only some fields in order not to overcomplicate the Dataset Preview and filter out some fields 

### Motivation

The `Results` dataset for the Open LLM Leaderboard contains json files with a complex nested structure. I would like to add `README.md` there to use the SQL console, for example. But if I describe the structure of this dataset completely, it will overcomplicate the use of Dataset Preview and the total number of columns will exceed 50 

### Your contribution

I'm afraid I'm not familiar with the project structure, so I won't be able to open a PR, but I'll try to help with something else if possible
Convert Array features to numpy arrays rather than lists by default
Author: alex-hh
State: open

### Feature request

It is currently quite easy to cause massive slowdowns when using datasets and not familiar with the underlying data conversions by e.g. making bad choices of formatting.

Would it be more user-friendly to set defaults that avoid this as much as possible? e.g. format Array features as numpy arrays rather than python lists

### Motivation

Default array formatting leads to slow performance: e.g.

```python
import numpy as np
from datasets import Dataset, Features, Array3D
features=Features(**{"array0": Array3D((None, 10, 10), dtype="float32"), "array1": Array3D((None,10,10), dtype="float32")})
dataset = Dataset.from_dict({f"array{i}": [np.zeros((x,10,10), dtype=np.float32) for x in [2000,1000]*25] for i in range(2)}, features=features)
```

```python
t0 = time.time()
for ex in ds:
   pass
t1 = time.time()
```
~1.4 s

```python
ds = dataset.to_iterable_dataset()
t0 = time.time()
for ex in ds:
    pass
t1 = time.time()
```
~10s

```python
ds = dataset.with_format("numpy")
t0 = time.time()
for ex in ds:
    pass
t1 = time.time()
```
~0.04s

```python
ds = dataset.to_iterable_dataset().with_format("numpy")
t0 = time.time()
for ex in ds:
    pass
t1 = time.time()
```
~0.04s

### Your contribution

May be able to contribute
Preserve features in iterable dataset.filter
Author: alex-hh
State: closed

Fixes example in #7208 - I'm not sure what other checks I should do? @lhoestq 

I also haven't thought hard about the concatenate / interleaving example iterables but think this might work assuming that features are either all identical or None?

Yes your assumption on concatenate/interleave is ok imo.

It seems the TypedExamplesIterable can slow down things, it should take formatting into account to not convert numpy arrays to python lists

right now it's slow (unrelatedly to your PR):

```python
>>> ds = Dataset.from_dict({"a": np.zeros((1000, 32, 32))}).to_iterable_dataset().with_format("np")
>>> filtered_ds = ds.filter(lambda x: True)
>>> %time sum(1 for _ in ds)
CPU times: user 175 ms, sys: 8.1 ms, total: 183 ms
Wall time: 184 ms
1000
>>> %time sum(1 for _ in filtered_ds)
CPU times: user 4.1 s, sys: 8.41 ms, total: 4.1 s
Wall time: 4.12 s
1000
```

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7209). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

> It seems the TypedExamplesIterable can slow down things, it should take formatting into account to not convert numpy arrays to python lists

Should be fixed by updated #7207 I hope!
Iterable dataset.filter should not override features
Author: alex-hh
State: closed

### Describe the bug

When calling filter on an iterable dataset, the features get set to None

### Steps to reproduce the bug

import numpy as np
import time
from datasets import Dataset, Features, Array3D

```python
features=Features(**{"array0": Array3D((None, 10, 10), dtype="float32"), "array1": Array3D((None,10,10), dtype="float32")})
dataset = Dataset.from_dict({f"array{i}": [np.zeros((x,10,10), dtype=np.float32) for x in [2000,1000]*25] for i in range(2)}, features=features)
ds = dataset.to_iterable_dataset()
orig_column_names = ds.column_names
ds = ds.filter(lambda x: True)
assert ds.column_names == orig_column_names
```

### Expected behavior

Filter should preserve features information

### Environment info

3.0.2

closed by https://github.com/huggingface/datasets/pull/7209, thanks @alex-hh !