functions

openml.datasets.functions

attributes_arff_from_df

attributes_arff_from_df(df: DataFrame) -> list[tuple[str, list[str] | str]]

Describe attributes of the dataframe according to ARFF specification.

PARAMETER	DESCRIPTION
df	The dataframe containing the data set. TYPE: (DataFrame, shape(n_samples, n_features))

RETURNS	DESCRIPTION
attributes_arff	The data set attributes as required by the ARFF format. TYPE: list[str]

Source code in openml/datasets/functions.py

def attributes_arff_from_df(df: pd.DataFrame) -> list[tuple[str, list[str] | str]]:
    """Describe attributes of the dataframe according to ARFF specification.

    Parameters
    ----------
    df : DataFrame, shape (n_samples, n_features)
        The dataframe containing the data set.

    Returns
    -------
    attributes_arff : list[str]
        The data set attributes as required by the ARFF format.
    """
    PD_DTYPES_TO_ARFF_DTYPE = {"integer": "INTEGER", "floating": "REAL", "string": "STRING"}
    attributes_arff: list[tuple[str, list[str] | str]] = []

    if not all(isinstance(column_name, str) for column_name in df.columns):
        logger.warning("Converting non-str column names to str.")
        df.columns = [str(column_name) for column_name in df.columns]

    for column_name in df:
        # skipna=True does not infer properly the dtype. The NA values are
        # dropped before the inference instead.
        column_dtype = pd.api.types.infer_dtype(df[column_name].dropna(), skipna=False)

        if column_dtype == "categorical":
            # for categorical feature, arff expects a list string. However, a
            # categorical column can contain mixed type and should therefore
            # raise an error asking to convert all entries to string.
            categories = df[column_name].cat.categories
            categories_dtype = pd.api.types.infer_dtype(categories)
            if categories_dtype not in ("string", "unicode"):
                raise ValueError(
                    f"The column '{column_name}' of the dataframe is of "
                    "'category' dtype. Therefore, all values in "
                    "this columns should be string. Please "
                    "convert the entries which are not string. "
                    f"Got {categories_dtype} dtype in this column.",
                )
            attributes_arff.append((column_name, categories.tolist()))
        elif column_dtype == "boolean":
            # boolean are encoded as categorical.
            attributes_arff.append((column_name, ["True", "False"]))
        elif column_dtype in PD_DTYPES_TO_ARFF_DTYPE:
            attributes_arff.append((column_name, PD_DTYPES_TO_ARFF_DTYPE[column_dtype]))
        else:
            raise ValueError(
                f"The dtype '{column_dtype}' of the column '{column_name}' is not "
                "currently supported by liac-arff. Supported "
                "dtypes are categorical, string, integer, "
                "floating, and boolean.",
            )
    return attributes_arff

check_datasets_active

check_datasets_active(dataset_ids: list[int], raise_error_if_not_exist: bool = True) -> dict[int, bool]

Check if the dataset ids provided are active.

Raises an error if a dataset_id in the given list of dataset_ids does not exist on the server and raise_error_if_not_exist is set to True (default).

PARAMETER	DESCRIPTION
dataset_ids	A list of integers representing dataset ids. TYPE: List[int]
raise_error_if_not_exist	Flag that if activated can raise an error, if one or more of the given dataset ids do not exist on the server. TYPE: bool(default=True) DEFAULT: True

RETURNS	DESCRIPTION
dict	A dictionary with items {did: bool}

Source code in openml/datasets/functions.py

def check_datasets_active(
    dataset_ids: list[int],
    raise_error_if_not_exist: bool = True,  # noqa: FBT002
) -> dict[int, bool]:
    """
    Check if the dataset ids provided are active.

    Raises an error if a dataset_id in the given list
    of dataset_ids does not exist on the server and
    `raise_error_if_not_exist` is set to True (default).

    Parameters
    ----------
    dataset_ids : List[int]
        A list of integers representing dataset ids.
    raise_error_if_not_exist : bool (default=True)
        Flag that if activated can raise an error, if one or more of the
        given dataset ids do not exist on the server.

    Returns
    -------
    dict
        A dictionary with items {did: bool}
    """
    datasets = list_datasets(status="all", data_id=dataset_ids)
    missing = set(dataset_ids) - set(datasets.index)
    if raise_error_if_not_exist and missing:
        missing_str = ", ".join(str(did) for did in missing)
        raise ValueError(f"Could not find dataset(s) {missing_str} in OpenML dataset list.")
    mask = datasets["status"] == "active"
    return dict(mask)

create_dataset

create_dataset(name: str, description: str | None, creator: str | None, contributor: str | None, collection_date: str | None, language: str | None, licence: str | None, attributes: list[tuple[str, str | list[str]]] | dict[str, str | list[str]] | Literal['auto'], data: DataFrame | ndarray | coo_matrix, default_target_attribute: str | None, ignore_attribute: str | list[str] | None, citation: str, row_id_attribute: str | None = None, original_data_url: str | None = None, paper_url: str | None = None, update_comment: str | None = None, version_label: str | None = None) -> OpenMLDataset

Create a dataset.

This function creates an OpenMLDataset object. The OpenMLDataset object contains information related to the dataset and the actual data file.

PARAMETER	DESCRIPTION
name	Name of the dataset. TYPE: str
description	Description of the dataset. TYPE: str
creator	The person who created the dataset. TYPE: str
contributor	People who contributed to the current version of the dataset. TYPE: str
collection_date	The date the data was originally collected, given by the uploader. TYPE: str
language	Language in which the data is represented. Starts with 1 upper case letter, rest lower case, e.g. 'English'. TYPE: str
licence	License of the data. TYPE: str
attributes	A list of tuples. Each tuple consists of the attribute name and type. If passing a pandas DataFrame, the attributes can be automatically inferred by passing 'auto'. Specific attributes can be manually specified by a passing a dictionary where the key is the name of the attribute and the value is the data type of the attribute. TYPE: list, dict, or 'auto'
data	An array that contains both the attributes and the targets. When providing a dataframe, the attribute names and type can be inferred by passing attributes='auto'. The target feature is indicated as meta-data of the dataset. TYPE: (ndarray, list, dataframe, coo_matrix, shape(n_samples, n_features))
default_target_attribute	The default target attribute, if it exists. Use None for unsupervised datasets (e.g. clustering, anomaly detection) where no natural target column exists. Can have multiple values, comma separated. TYPE: str
ignore_attribute	Attributes that should be excluded in modelling, such as identifiers and indexes. Can have multiple values, comma separated. TYPE: str | list
citation	Reference(s) that should be cited when building on this data. TYPE: str
version_label	Version label provided by user. Can be a date, hash, or some other type of id. TYPE: str DEFAULT: None
row_id_attribute	The attribute that represents the row-id column, if present in the dataset. If data is a dataframe and row_id_attribute is not specified, the index of the dataframe will be used as the row_id_attribute. If the name of the index is None, it will be discarded. .. versionadded: 0.8 Inference of row_id_attribute from a dataframe. TYPE: str DEFAULT: None
original_data_url	For derived data, the url to the original dataset. TYPE: str DEFAULT: None
paper_url	Link to a paper describing the dataset. TYPE: str DEFAULT: None
update_comment	An explanation for when the dataset is uploaded. TYPE: str DEFAULT: None

RETURNS	DESCRIPTION
class	TYPE: `openml.OpenMLDataset`
Dataset description.

Source code in openml/datasets/functions.py

def create_dataset(  # noqa: C901, PLR0912, PLR0915
    name: str,
    description: str | None,
    creator: str | None,
    contributor: str | None,
    collection_date: str | None,
    language: str | None,
    licence: str | None,
    # TODO(eddiebergman): Docstring says `type` but I don't know what this is other than strings
    # Edit: Found it could also be like ["True", "False"]
    attributes: list[tuple[str, str | list[str]]] | dict[str, str | list[str]] | Literal["auto"],
    data: pd.DataFrame | np.ndarray | scipy.sparse.coo_matrix,
    default_target_attribute: str | None,
    ignore_attribute: str | list[str] | None,
    citation: str,
    row_id_attribute: str | None = None,
    original_data_url: str | None = None,
    paper_url: str | None = None,
    update_comment: str | None = None,
    version_label: str | None = None,
) -> OpenMLDataset:
    """Create a dataset.

    This function creates an OpenMLDataset object.
    The OpenMLDataset object contains information related to the dataset
    and the actual data file.

    Parameters
    ----------
    name : str
        Name of the dataset.
    description : str
        Description of the dataset.
    creator : str
        The person who created the dataset.
    contributor : str
        People who contributed to the current version of the dataset.
    collection_date : str
        The date the data was originally collected, given by the uploader.
    language : str
        Language in which the data is represented.
        Starts with 1 upper case letter, rest lower case, e.g. 'English'.
    licence : str
        License of the data.
    attributes : list, dict, or 'auto'
        A list of tuples. Each tuple consists of the attribute name and type.
        If passing a pandas DataFrame, the attributes can be automatically
        inferred by passing ``'auto'``. Specific attributes can be manually
        specified by a passing a dictionary where the key is the name of the
        attribute and the value is the data type of the attribute.
    data : ndarray, list, dataframe, coo_matrix, shape (n_samples, n_features)
        An array that contains both the attributes and the targets. When
        providing a dataframe, the attribute names and type can be inferred by
        passing ``attributes='auto'``.
        The target feature is indicated as meta-data of the dataset.
    default_target_attribute : str
        The default target attribute, if it exists. Use ``None`` for unsupervised datasets
        (e.g. clustering, anomaly detection) where no natural target column exists.
        Can have multiple values, comma separated.
    ignore_attribute : str | list
        Attributes that should be excluded in modelling,
        such as identifiers and indexes.
        Can have multiple values, comma separated.
    citation : str
        Reference(s) that should be cited when building on this data.
    version_label : str, optional
        Version label provided by user.
         Can be a date, hash, or some other type of id.
    row_id_attribute : str, optional
        The attribute that represents the row-id column, if present in the
        dataset. If ``data`` is a dataframe and ``row_id_attribute`` is not
        specified, the index of the dataframe will be used as the
        ``row_id_attribute``. If the name of the index is ``None``, it will
        be discarded.

        .. versionadded: 0.8
            Inference of ``row_id_attribute`` from a dataframe.
    original_data_url : str, optional
        For derived data, the url to the original dataset.
    paper_url : str, optional
        Link to a paper describing the dataset.
    update_comment : str, optional
        An explanation for when the dataset is uploaded.

    Returns
    -------
    class:`openml.OpenMLDataset`
    Dataset description.
    """
    if isinstance(data, pd.DataFrame):
        # infer the row id from the index of the dataset
        if row_id_attribute is None:
            row_id_attribute = data.index.name
        # When calling data.values, the index will be skipped.
        # We need to reset the index such that it is part of the data.
        if data.index.name is not None:
            data = data.reset_index()

    if attributes == "auto" or isinstance(attributes, dict):
        if not isinstance(data, pd.DataFrame):
            raise ValueError(
                "Automatically inferring attributes requires "
                f"a pandas DataFrame. A {data!r} was given instead.",
            )
        # infer the type of data for each column of the DataFrame
        attributes_ = attributes_arff_from_df(data)
        if isinstance(attributes, dict):
            # override the attributes which was specified by the user
            for attr_idx in range(len(attributes_)):
                attr_name = attributes_[attr_idx][0]
                if attr_name in attributes:
                    attributes_[attr_idx] = (attr_name, attributes[attr_name])
    else:
        attributes_ = attributes
    ignore_attributes = _expand_parameter(ignore_attribute)
    _validated_data_attributes(ignore_attributes, attributes_, "ignore_attribute")

    default_target_attributes = _expand_parameter(default_target_attribute)
    _validated_data_attributes(default_target_attributes, attributes_, "default_target_attribute")

    if row_id_attribute is not None:
        is_row_id_an_attribute = any(attr[0] == row_id_attribute for attr in attributes_)
        if not is_row_id_an_attribute:
            raise ValueError(
                "'row_id_attribute' should be one of the data attribute. "
                f" Got '{row_id_attribute}' while candidates are"
                f" {[attr[0] for attr in attributes_]}.",
            )

    if isinstance(data, pd.DataFrame):
        if all(isinstance(dtype, pd.SparseDtype) for dtype in data.dtypes):
            data = data.sparse.to_coo()
            # liac-arff only support COO matrices with sorted rows
            row_idx_sorted = np.argsort(data.row)  # type: ignore
            data.row = data.row[row_idx_sorted]  # type: ignore
            data.col = data.col[row_idx_sorted]  # type: ignore
            data.data = data.data[row_idx_sorted]  # type: ignore
        else:
            data = data.to_numpy()

    data_format: Literal["arff", "sparse_arff"]
    if isinstance(data, (list, np.ndarray)):
        if isinstance(data[0], (list, np.ndarray)):
            data_format = "arff"
        elif isinstance(data[0], dict):
            data_format = "sparse_arff"
        else:
            raise ValueError(
                "When giving a list or a numpy.ndarray, "
                "they should contain a list/ numpy.ndarray "
                "for dense data or a dictionary for sparse "
                f"data. Got {data[0]!r} instead.",
            )
    elif isinstance(data, coo_matrix):
        data_format = "sparse_arff"
    else:
        raise ValueError(
            "When giving a list or a numpy.ndarray, "
            "they should contain a list/ numpy.ndarray "
            "for dense data or a dictionary for sparse "
            f"data. Got {data[0]!r} instead.",
        )

    arff_object = {
        "relation": name,
        "description": description,
        "attributes": attributes_,
        "data": data,
    }

    # serializes the ARFF dataset object and returns a string
    arff_dataset = arff.dumps(arff_object)
    try:
        # check if ARFF is valid
        decoder = arff.ArffDecoder()
        return_type = arff.COO if data_format == "sparse_arff" else arff.DENSE
        decoder.decode(arff_dataset, encode_nominal=True, return_type=return_type)
    except arff.ArffException as e:
        raise ValueError(
            "The arguments you have provided do not construct a valid ARFF file"
        ) from e

    return OpenMLDataset(
        name=name,
        description=description,
        data_format=data_format,
        creator=creator,
        contributor=contributor,
        collection_date=collection_date,
        language=language,
        licence=licence,
        default_target_attribute=default_target_attribute,
        row_id_attribute=row_id_attribute,
        ignore_attribute=ignore_attribute,
        citation=citation,
        version_label=version_label,
        original_data_url=original_data_url,
        paper_url=paper_url,
        update_comment=update_comment,
        dataset=arff_dataset,
    )

data_feature_add_ontology

data_feature_add_ontology(data_id: int, index: int, ontology: str) -> bool

An ontology describes the concept that are described in a feature. An ontology is defined by an URL where the information is provided. Adds an ontology (URL) to a given dataset feature (defined by a dataset id and index). The dataset has to exists on OpenML and needs to have been processed by the evaluation engine.

PARAMETER	DESCRIPTION
data_id	id of the dataset to which the feature belongs TYPE: int
index	index of the feature in dataset (0-based) TYPE: int
ontology	URL to ontology (max. 256 characters) TYPE: str

RETURNS	DESCRIPTION
True or throws an OpenML server exception

Source code in openml/datasets/functions.py

def data_feature_add_ontology(data_id: int, index: int, ontology: str) -> bool:
    """
    An ontology describes the concept that are described in a feature. An
    ontology is defined by an URL where the information is provided. Adds
    an ontology (URL) to a given dataset feature (defined by a dataset id
    and index). The dataset has to exists on OpenML and needs to have been
    processed by the evaluation engine.

    Parameters
    ----------
    data_id : int
        id of the dataset to which the feature belongs
    index : int
        index of the feature in dataset (0-based)
    ontology : str
        URL to ontology (max. 256 characters)

    Returns
    -------
    True or throws an OpenML server exception
    """
    return openml._backend.dataset.feature_add_ontology(data_id, index, ontology)

data_feature_remove_ontology

data_feature_remove_ontology(data_id: int, index: int, ontology: str) -> bool

Removes an existing ontology (URL) from a given dataset feature (defined by a dataset id and index). The dataset has to exists on OpenML and needs to have been processed by the evaluation engine. Ontology needs to be attached to the specific fearure.

PARAMETER	DESCRIPTION
data_id	id of the dataset to which the feature belongs TYPE: int
index	index of the feature in dataset (0-based) TYPE: int
ontology	URL to ontology (max. 256 characters) TYPE: str

RETURNS	DESCRIPTION
True or throws an OpenML server exception

Source code in openml/datasets/functions.py

def data_feature_remove_ontology(data_id: int, index: int, ontology: str) -> bool:
    """
    Removes an existing ontology (URL) from a given dataset feature (defined
    by a dataset id and index). The dataset has to exists on OpenML and needs
    to have been processed by the evaluation engine. Ontology needs to be
    attached to the specific fearure.

    Parameters
    ----------
    data_id : int
        id of the dataset to which the feature belongs
    index : int
        index of the feature in dataset (0-based)
    ontology : str
        URL to ontology (max. 256 characters)

    Returns
    -------
    True or throws an OpenML server exception
    """
    return openml._backend.dataset.feature_remove_ontology(data_id, index, ontology)

delete_dataset

delete_dataset(dataset_id: int) -> bool

Delete dataset with id dataset_id from the OpenML server.

This can only be done if you are the owner of the dataset and no tasks are attached to the dataset.

PARAMETER	DESCRIPTION
dataset_id	OpenML id of the dataset TYPE: int

RETURNS	DESCRIPTION
bool	True if the deletion was successful. False otherwise.

Source code in openml/datasets/functions.py

def delete_dataset(dataset_id: int) -> bool:
    """Delete dataset with id `dataset_id` from the OpenML server.

    This can only be done if you are the owner of the dataset and
    no tasks are attached to the dataset.

    Parameters
    ----------
    dataset_id : int
        OpenML id of the dataset

    Returns
    -------
    bool
        True if the deletion was successful. False otherwise.
    """
    return openml._backend.dataset.delete(dataset_id)

edit_dataset

edit_dataset(data_id: int, description: str | None = None, creator: str | None = None, contributor: str | None = None, collection_date: str | None = None, language: str | None = None, default_target_attribute: str | None = None, ignore_attribute: str | list[str] | None = None, citation: str | None = None, row_id_attribute: str | None = None, original_data_url: str | None = None, paper_url: str | None = None) -> int

Edits an OpenMLDataset.

In addition to providing the dataset id of the dataset to edit (through data_id), you must specify a value for at least one of the optional function arguments, i.e. one value for a field to edit.

This function allows editing of both non-critical and critical fields. Critical fields are default_target_attribute, ignore_attribute, row_id_attribute.

• Editing non-critical data fields is allowed for all authenticated users.
• Editing critical fields is allowed only for the owner, provided there are no tasks associated with this dataset.

If dataset has tasks or if the user is not the owner, the only way to edit critical fields is to use fork_dataset followed by edit_dataset.

PARAMETER	DESCRIPTION
data_id	ID of the dataset. TYPE: int
description	Description of the dataset. TYPE: str DEFAULT: None
creator	The person who created the dataset. TYPE: str DEFAULT: None
contributor	People who contributed to the current version of the dataset. TYPE: str DEFAULT: None
collection_date	The date the data was originally collected, given by the uploader. TYPE: str DEFAULT: None
language	Language in which the data is represented. Starts with 1 upper case letter, rest lower case, e.g. 'English'. TYPE: str DEFAULT: None
default_target_attribute	The default target attribute, if it exists. Can have multiple values, comma separated. TYPE: str DEFAULT: None
ignore_attribute	Attributes that should be excluded in modelling, such as identifiers and indexes. TYPE: str | list DEFAULT: None
citation	Reference(s) that should be cited when building on this data. TYPE: str DEFAULT: None
row_id_attribute	The attribute that represents the row-id column, if present in the dataset. If data is a dataframe and row_id_attribute is not specified, the index of the dataframe will be used as the row_id_attribute. If the name of the index is None, it will be discarded. .. versionadded: 0.8 Inference of row_id_attribute from a dataframe. TYPE: str DEFAULT: None
original_data_url	For derived data, the url to the original dataset. TYPE: str DEFAULT: None
paper_url	Link to a paper describing the dataset. TYPE: str DEFAULT: None

RETURNS	DESCRIPTION
Dataset id

Source code in openml/datasets/functions.py

def edit_dataset(
    data_id: int,
    description: str | None = None,
    creator: str | None = None,
    contributor: str | None = None,
    collection_date: str | None = None,
    language: str | None = None,
    default_target_attribute: str | None = None,
    ignore_attribute: str | list[str] | None = None,
    citation: str | None = None,
    row_id_attribute: str | None = None,
    original_data_url: str | None = None,
    paper_url: str | None = None,
) -> int:
    """Edits an OpenMLDataset.

    In addition to providing the dataset id of the dataset to edit (through data_id),
    you must specify a value for at least one of the optional function arguments,
    i.e. one value for a field to edit.

    This function allows editing of both non-critical and critical fields.
    Critical fields are default_target_attribute, ignore_attribute, row_id_attribute.

     - Editing non-critical data fields is allowed for all authenticated users.
     - Editing critical fields is allowed only for the owner, provided there are no tasks
       associated with this dataset.

    If dataset has tasks or if the user is not the owner, the only way
    to edit critical fields is to use fork_dataset followed by edit_dataset.

    Parameters
    ----------
    data_id : int
        ID of the dataset.
    description : str
        Description of the dataset.
    creator : str
        The person who created the dataset.
    contributor : str
        People who contributed to the current version of the dataset.
    collection_date : str
        The date the data was originally collected, given by the uploader.
    language : str
        Language in which the data is represented.
        Starts with 1 upper case letter, rest lower case, e.g. 'English'.
    default_target_attribute : str
        The default target attribute, if it exists.
        Can have multiple values, comma separated.
    ignore_attribute : str | list
        Attributes that should be excluded in modelling,
        such as identifiers and indexes.
    citation : str
        Reference(s) that should be cited when building on this data.
    row_id_attribute : str, optional
        The attribute that represents the row-id column, if present in the
        dataset. If ``data`` is a dataframe and ``row_id_attribute`` is not
        specified, the index of the dataframe will be used as the
        ``row_id_attribute``. If the name of the index is ``None``, it will
        be discarded.

        .. versionadded: 0.8
            Inference of ``row_id_attribute`` from a dataframe.
    original_data_url : str, optional
        For derived data, the url to the original dataset.
    paper_url : str, optional
        Link to a paper describing the dataset.

    Returns
    -------
    Dataset id
    """
    if not isinstance(data_id, int):
        raise TypeError(f"`data_id` must be of type `int`, not {type(data_id)}.")

    if not any(
        field
        for field in [
            description,
            creator,
            contributor,
            collection_date,
            language,
            default_target_attribute,
            ignore_attribute,
            citation,
            row_id_attribute,
            original_data_url,
            paper_url,
        ]
    ):
        raise ValueError(
            "Please provide atleast one field among description, creator, "
            "contributor, collection_date, language, citation, "
            "original_data_url, default_target_attribute, row_id_attribute, "
            "ignore_attribute or paper_url to edit.",
        )

    return openml._backend.dataset.edit(
        data_id,
        description=description,
        creator=creator,
        contributor=contributor,
        collection_date=collection_date,
        language=language,
        default_target_attribute=default_target_attribute,
        ignore_attribute=ignore_attribute,
        citation=citation,
        row_id_attribute=row_id_attribute,
        original_data_url=original_data_url,
        paper_url=paper_url,
    )

fork_dataset

fork_dataset(data_id: int) -> int

Creates a new dataset version, with the authenticated user as the new owner. The forked dataset can have distinct dataset meta-data, but the actual data itself is shared with the original version.

This API is intended for use when a user is unable to edit the critical fields of a dataset through the edit_dataset API. (Critical fields are default_target_attribute, ignore_attribute, row_id_attribute.)

Specifically, this happens when the user is: 1. Not the owner of the dataset. 2. User is the owner of the dataset, but the dataset has tasks.

In these two cases the only way to edit critical fields is: 1. STEP 1: Fork the dataset using fork_dataset API 2. STEP 2: Call edit_dataset API on the forked version.

PARAMETER	DESCRIPTION
data_id	id of the dataset to be forked TYPE: int

RETURNS	DESCRIPTION
Dataset id of the forked dataset

Source code in openml/datasets/functions.py

def fork_dataset(data_id: int) -> int:
    """
     Creates a new dataset version, with the authenticated user as the new owner.
     The forked dataset can have distinct dataset meta-data,
     but the actual data itself is shared with the original version.

     This API is intended for use when a user is unable to edit the critical fields of a dataset
     through the edit_dataset API.
     (Critical fields are default_target_attribute, ignore_attribute, row_id_attribute.)

     Specifically, this happens when the user is:
            1. Not the owner of the dataset.
            2. User is the owner of the dataset, but the dataset has tasks.

     In these two cases the only way to edit critical fields is:
            1. STEP 1: Fork the dataset using fork_dataset API
            2. STEP 2: Call edit_dataset API on the forked version.


    Parameters
    ----------
    data_id : int
        id of the dataset to be forked

    Returns
    -------
    Dataset id of the forked dataset

    """
    if not isinstance(data_id, int):
        raise TypeError(f"`data_id` must be of type `int`, not {type(data_id)}.")

    return openml._backend.dataset.fork(dataset_id=data_id)

get_dataset

get_dataset(dataset_id: int | str, download_data: bool = False, version: int | None = None, error_if_multiple: bool = False, cache_format: Literal['pickle', 'feather'] = 'pickle', download_qualities: bool = False, download_features_meta_data: bool = False, download_all_files: bool = False, force_refresh_cache: bool = False) -> OpenMLDataset

Download the OpenML dataset representation, optionally also download actual data file.

This function is by default NOT thread/multiprocessing safe, as this function uses caching. A check will be performed to determine if the information has previously been downloaded to a cache, and if so be loaded from disk instead of retrieved from the server.

To make this function thread safe, you can install the python package oslo.concurrency. If oslo.concurrency is installed get_dataset becomes thread safe.

Alternatively, to make this function thread/multiprocessing safe initialize the cache first by calling get_dataset(args) once before calling get_dataset(args) many times in parallel. This will initialize the cache and later calls will use the cache in a thread/multiprocessing safe way.

If dataset is retrieved by name, a version may be specified. If no version is specified and multiple versions of the dataset exist, the earliest version of the dataset that is still active will be returned. If no version is specified, multiple versions of the dataset exist and exception_if_multiple is set to True, this function will raise an exception.

PARAMETER	DESCRIPTION
dataset_id	Dataset ID (integer) or dataset name (string) of the dataset to download. TYPE: int or str
download_data	If True, also download the data file. Beware that some datasets are large and it might make the operation noticeably slower. Metadata is also still retrieved. If False, create the OpenMLDataset and only populate it with the metadata. The data may later be retrieved through the OpenMLDataset.get_data method. TYPE: bool(default=False) DEFAULT: False
version	Specifies the version if dataset_id is specified by name. If no version is specified, retrieve the least recent still active version. TYPE: (int, optional(default=None)) DEFAULT: None
error_if_multiple	If True raise an error if multiple datasets are found with matching criteria. TYPE: bool(default=False) DEFAULT: False
cache_format	Format for caching the dataset - may be feather or pickle Note that the default 'pickle' option may load slower than feather when no.of.rows is very high. TYPE: str(default='pickle') in {'pickle', 'feather'} DEFAULT: 'pickle'
download_qualities	Option to download 'qualities' meta-data in addition to the minimal dataset description. If True, download and cache the qualities file. If False, create the OpenMLDataset without qualities metadata. The data may later be added to the OpenMLDataset through the OpenMLDataset.load_metadata(qualities=True) method. TYPE: bool(default=False) DEFAULT: False
download_features_meta_data	Option to download 'features' meta-data in addition to the minimal dataset description. If True, download and cache the features file. If False, create the OpenMLDataset without features metadata. The data may later be added to the OpenMLDataset through the OpenMLDataset.load_metadata(features=True) method. TYPE: bool(default=False) DEFAULT: False
download_all_files	EXPERIMENTAL. Download all files related to the dataset that reside on the server. Useful for datasets which refer to auxiliary files (e.g., meta-album). TYPE: bool DEFAULT: False
force_refresh_cache	Force the cache to refreshed by deleting the cache directory and re-downloading the data. Note, if force_refresh_cache is True, get_dataset is NOT thread/multiprocessing safe, because this creates a race condition to creating and deleting the cache; as in general with the cache. TYPE: bool(default=False) DEFAULT: False

RETURNS	DESCRIPTION
dataset	The downloaded dataset. TYPE: :class:`openml.OpenMLDataset`

Examples:

>>> import openml
>>> dataset = openml.datasets.get_dataset(1)
>>> dataset = openml.datasets.get_dataset("iris", version=1)
>>> dataset = openml.datasets.get_dataset(1, download_data=True)

Source code in openml/datasets/functions.py

@openml.utils.thread_safe_if_oslo_installed
def get_dataset(
    dataset_id: int | str,
    download_data: bool = False,  # noqa: FBT002
    version: int | None = None,
    error_if_multiple: bool = False,  # noqa: FBT002
    cache_format: Literal["pickle", "feather"] = "pickle",
    download_qualities: bool = False,  # noqa: FBT002
    download_features_meta_data: bool = False,  # noqa: FBT002
    download_all_files: bool = False,  # noqa: FBT002
    force_refresh_cache: bool = False,  # noqa: FBT002
) -> OpenMLDataset:
    """Download the OpenML dataset representation, optionally also download actual data file.

    This function is by default NOT thread/multiprocessing safe, as this function uses caching.
    A check will be performed to determine if the information has previously been downloaded to a
    cache, and if so be loaded from disk instead of retrieved from the server.

    To make this function thread safe, you can install the python package ``oslo.concurrency``.
    If ``oslo.concurrency`` is installed `get_dataset` becomes thread safe.

    Alternatively, to make this function thread/multiprocessing safe initialize the cache first by
    calling `get_dataset(args)` once before calling `get_dataset(args)` many times in parallel.
    This will initialize the cache and later calls will use the cache in a thread/multiprocessing
    safe way.

    If dataset is retrieved by name, a version may be specified.
    If no version is specified and multiple versions of the dataset exist,
    the earliest version of the dataset that is still active will be returned.
    If no version is specified, multiple versions of the dataset exist and
    ``exception_if_multiple`` is set to ``True``, this function will raise an exception.

    Parameters
    ----------
    dataset_id : int or str
        Dataset ID (integer) or dataset name (string) of the dataset to download.
    download_data : bool (default=False)
        If True, also download the data file. Beware that some datasets are large and it might
        make the operation noticeably slower. Metadata is also still retrieved.
        If False, create the OpenMLDataset and only populate it with the metadata.
        The data may later be retrieved through the `OpenMLDataset.get_data` method.
    version : int, optional (default=None)
        Specifies the version if `dataset_id` is specified by name.
        If no version is specified, retrieve the least recent still active version.
    error_if_multiple : bool (default=False)
        If ``True`` raise an error if multiple datasets are found with matching criteria.
    cache_format : str (default='pickle') in {'pickle', 'feather'}
        Format for caching the dataset - may be feather or pickle
        Note that the default 'pickle' option may load slower than feather when
        no.of.rows is very high.
    download_qualities : bool (default=False)
        Option to download 'qualities' meta-data in addition to the minimal dataset description.
        If True, download and cache the qualities file.
        If False, create the OpenMLDataset without qualities metadata. The data may later be added
        to the OpenMLDataset through the `OpenMLDataset.load_metadata(qualities=True)` method.
    download_features_meta_data : bool (default=False)
        Option to download 'features' meta-data in addition to the minimal dataset description.
        If True, download and cache the features file.
        If False, create the OpenMLDataset without features metadata. The data may later be added
        to the OpenMLDataset through the `OpenMLDataset.load_metadata(features=True)` method.
    download_all_files: bool (default=False)
        EXPERIMENTAL. Download all files related to the dataset that reside on the server.
        Useful for datasets which refer to auxiliary files (e.g., meta-album).
    force_refresh_cache : bool (default=False)
        Force the cache to refreshed by deleting the cache directory and re-downloading the data.
        Note, if `force_refresh_cache` is True, `get_dataset` is NOT thread/multiprocessing safe,
        because this creates a race condition to creating and deleting the cache; as in general with
        the cache.

    Returns
    -------
    dataset : :class:`openml.OpenMLDataset`
        The downloaded dataset.

    Examples
    --------
    >>> import openml
    >>> dataset = openml.datasets.get_dataset(1)  # doctest: +SKIP
    >>> dataset = openml.datasets.get_dataset("iris", version=1)  # doctest: +SKIP
    >>> dataset = openml.datasets.get_dataset(1, download_data=True)  # doctest: +SKIP
    """
    if download_all_files:
        warnings.warn(
            "``download_all_files`` is experimental and is likely to break with new releases.",
            FutureWarning,
            stacklevel=2,
        )

    if cache_format not in ["feather", "pickle"]:
        raise ValueError(
            "cache_format must be one of 'feather' or 'pickle. "
            f"Invalid format specified: {cache_format}",
        )

    if isinstance(dataset_id, str):
        try:
            dataset_id = int(dataset_id)
        except ValueError:
            dataset_id = _name_to_id(dataset_id, version, error_if_multiple)  # type: ignore
    elif not isinstance(dataset_id, int):
        raise TypeError(
            f"`dataset_id` must be one of `str` or `int`, not {type(dataset_id)}.",
        )

    return openml._backend.dataset.get(
        dataset_id,
        download_data=download_data,
        cache_format=cache_format,
        download_qualities=download_qualities,
        download_features_meta_data=download_features_meta_data,
        download_all_files=download_all_files,
        force_refresh_cache=force_refresh_cache,
    )

get_datasets

get_datasets(dataset_ids: list[str | int], download_data: bool = False, download_qualities: bool = False) -> list[OpenMLDataset]

Download datasets.

This function iterates :meth:openml.datasets.get_dataset.

PARAMETER	DESCRIPTION
dataset_ids	Integers or strings representing dataset ids or dataset names. If dataset names are specified, the least recent still active dataset version is returned. TYPE: iterable
download_data	If True, also download the data file. Beware that some datasets are large and it might make the operation noticeably slower. Metadata is also still retrieved. If False, create the OpenMLDataset and only populate it with the metadata. The data may later be retrieved through the OpenMLDataset.get_data method. TYPE: bool DEFAULT: False
download_qualities	If True, also download qualities.xml file. If False it skip the qualities.xml. TYPE: (bool, optional(default=True)) DEFAULT: False

RETURNS	DESCRIPTION
datasets	A list of dataset objects. TYPE: list of datasets

Examples:

>>> import openml
>>> datasets = openml.datasets.get_datasets([1, 2, 3])

Source code in openml/datasets/functions.py

def get_datasets(
    dataset_ids: list[str | int],
    download_data: bool = False,  # noqa: FBT002
    download_qualities: bool = False,  # noqa: FBT002
) -> list[OpenMLDataset]:
    """Download datasets.

    This function iterates :meth:`openml.datasets.get_dataset`.

    Parameters
    ----------
    dataset_ids : iterable
        Integers or strings representing dataset ids or dataset names.
        If dataset names are specified, the least recent still active dataset version is returned.
    download_data : bool, optional
        If True, also download the data file. Beware that some datasets are large and it might
        make the operation noticeably slower. Metadata is also still retrieved.
        If False, create the OpenMLDataset and only populate it with the metadata.
        The data may later be retrieved through the `OpenMLDataset.get_data` method.
    download_qualities : bool, optional (default=True)
        If True, also download qualities.xml file. If False it skip the qualities.xml.

    Returns
    -------
    datasets : list of datasets
        A list of dataset objects.

    Examples
    --------
    >>> import openml
    >>> datasets = openml.datasets.get_datasets([1, 2, 3])  # doctest: +SKIP
    """
    datasets = []
    for dataset_id in dataset_ids:
        datasets.append(
            get_dataset(dataset_id, download_data, download_qualities=download_qualities),
        )
    return datasets

list_datasets

list_datasets(data_id: list[int] | None = None, offset: int | None = None, size: int | None = None, status: str | None = None, tag: str | None = None, data_name: str | None = None, data_version: int | None = None, number_instances: int | str | None = None, number_features: int | str | None = None, number_classes: int | str | None = None, number_missing_values: int | str | None = None) -> DataFrame

Return a dataframe of all dataset which are on OpenML.

Supports large amount of results.

PARAMETER	DESCRIPTION
data_id	A list of data ids, to specify which datasets should be listed TYPE: list DEFAULT: None
offset	The number of datasets to skip, starting from the first. TYPE: int DEFAULT: None
size	The maximum number of datasets to show. TYPE: int DEFAULT: None
status	Should be {active, in_preparation, deactivated}. By default active datasets are returned, but also datasets from another status can be requested. TYPE: str DEFAULT: None
tag	TYPE: str DEFAULT: None
data_name	TYPE: str DEFAULT: None
data_version	TYPE: int DEFAULT: None
number_instances	TYPE: int | str DEFAULT: None
number_features	TYPE: int | str DEFAULT: None
number_classes	TYPE: int | str DEFAULT: None
number_missing_values	TYPE: int | str DEFAULT: None

RETURNS	DESCRIPTION
datasets	Each row maps to a dataset Each column contains the following information: - dataset id - name - format - status If qualities are calculated for the dataset, some of these are also included as columns. TYPE: dataframe

Source code in openml/datasets/functions.py

def list_datasets(
    data_id: list[int] | None = None,
    offset: int | None = None,
    size: int | None = None,
    status: str | None = None,
    tag: str | None = None,
    data_name: str | None = None,
    data_version: int | None = None,
    number_instances: int | str | None = None,
    number_features: int | str | None = None,
    number_classes: int | str | None = None,
    number_missing_values: int | str | None = None,
) -> pd.DataFrame:
    """Return a dataframe of all dataset which are on OpenML.

    Supports large amount of results.

    Parameters
    ----------
    data_id : list, optional
        A list of data ids, to specify which datasets should be
        listed
    offset : int, optional
        The number of datasets to skip, starting from the first.
    size : int, optional
        The maximum number of datasets to show.
    status : str, optional
        Should be {active, in_preparation, deactivated}. By
        default active datasets are returned, but also datasets
        from another status can be requested.
    tag : str, optional
    data_name : str, optional
    data_version : int, optional
    number_instances : int | str, optional
    number_features : int | str, optional
    number_classes : int | str, optional
    number_missing_values : int | str, optional

    Returns
    -------
    datasets: dataframe
        Each row maps to a dataset
        Each column contains the following information:
        - dataset id
        - name
        - format
        - status
        If qualities are calculated for the dataset, some of
        these are also included as columns.
    """
    listing_call = partial(
        openml._backend.dataset.list,
        data_id=data_id,
        status=status,
        tag=tag,
        data_name=data_name,
        data_version=data_version,
        number_instances=number_instances,
        number_features=number_features,
        number_classes=number_classes,
        number_missing_values=number_missing_values,
    )
    batches = openml.utils._list_all(listing_call, offset=offset, limit=size)
    if len(batches) == 0:
        return pd.DataFrame()

    return pd.concat(batches)

list_qualities

list_qualities() -> list[str]

Return list of data qualities available.

The function performs an API call to retrieve the entire list of data qualities that are computed on the datasets uploaded.

RETURNS	DESCRIPTION
list

Source code in openml/datasets/functions.py

def list_qualities() -> list[str]:
    """Return list of data qualities available.

    The function performs an API call to retrieve the entire list of
    data qualities that are computed on the datasets uploaded.

    Returns
    -------
    list
    """
    return openml._backend.dataset.list_qualities()

status_update

status_update(data_id: int, status: Literal['active', 'deactivated']) -> None

Updates the status of a dataset to either 'active' or 'deactivated'. Please see the OpenML API documentation for a description of the status and all legal status transitions: docs.openml.org/concepts/data/#dataset-status

PARAMETER	DESCRIPTION
data_id	The data id of the dataset TYPE: int
status	'active' or 'deactivated' TYPE: (str,)

Source code in openml/datasets/functions.py

def status_update(data_id: int, status: Literal["active", "deactivated"]) -> None:
    """
    Updates the status of a dataset to either 'active' or 'deactivated'.
    Please see the OpenML API documentation for a description of the status
    and all legal status transitions:
    https://docs.openml.org/concepts/data/#dataset-status

    Parameters
    ----------
    data_id : int
        The data id of the dataset
    status : str,
        'active' or 'deactivated'
    """
    legal_status = {"active", "deactivated"}
    if status not in legal_status:
        raise ValueError(f"Illegal status value. Legal values: {legal_status}")

    openml._backend.dataset.status_update(dataset_id=data_id, status=status)