Class Indexes

xarray/core/indexes.py:1685–1954

Immutable proxy for Dataset or DataArray indexes. It is a mapping where keys are coordinate names and values are either pandas or xarray indexes. It also contains the indexed coordinate variables and provides some utility methods.

class Indexes(collections.abc.Mapping, Generic[T_PandasOrXarrayIndex]):
    """Immutable proxy for Dataset or DataArray indexes.

    It is a mapping where keys are coordinate names and values are either pandas
    or xarray indexes.

    It also contains the indexed coordinate variables and provides some utility
    methods.

    """

    _index_type: type[Index | pd.Index]
    _indexes: dict[Any, T_PandasOrXarrayIndex]
    _variables: dict[Any, Variable]

    __slots__ = (
        "__coord_name_id",
        "__id_coord_names",
        "__id_index",
        "_dims",
        "_index_type",
        "_indexes",
        "_variables",
    )

    def __init__(
        self,
        indexes: Mapping[Any, T_PandasOrXarrayIndex] | None = None,
        variables: Mapping[Any, Variable] | None = None,
        index_type: type[Index | pd.Index] = Index,
    ):
        """Constructor not for public consumption.

        Parameters
        ----------
        indexes : dict
            Indexes held by this object.
        variables : dict
            Indexed coordinate variables in this object. Entries must
            match those of `indexes`.
        index_type : type
            The type of all indexes, i.e., either :py:class:`xarray.indexes.Index`
            or :py:class:`pandas.Index`.

        """
        if indexes is None:
            indexes = {}
        if variables is None:
            variables = {}

        unmatched_keys = set(indexes) ^ set(variables)
        if unmatched_keys:
            raise ValueError(
                f"unmatched keys found in indexes and variables: {unmatched_keys}"
            )

        if any(not isinstance(idx, index_type) for idx in indexes.values()):
            index_type_str = f"{index_type.__module__}.{index_type.__name__}"