open

zarr.open

open(
    store: StoreLike | None = None,
    *,
    mode: AccessModeLiteral | None = None,
    zarr_version: ZarrFormat | None = None,
    zarr_format: ZarrFormat | None = None,
    path: str | None = None,
    storage_options: dict[str, Any] | None = None,
    **kwargs: Any,
) -> Array | Group

Open a group or array using file-mode-like semantics.

Parameters:

• store (StoreLike or None, default: None ) –

  Store or path to directory in file system or name of zip file.

• mode (('r', 'r+', 'a', 'w', 'w-'), default: 'r' ) –

  Persistence mode: 'r' means read only (must exist); 'r+' means read/write (must exist); 'a' means read/write (create if doesn't exist); 'w' means create (overwrite if exists); 'w-' means create (fail if exists). If the store is read-only, the default is 'r'; otherwise, it is 'a'.

• zarr_format ((2, 3, None), default: 2 ) –

  The zarr format to use when saving.

• path (str or None, default: None ) –

  The path within the store to open.

• storage_options (dict, default: None ) –

  If using an fsspec URL to create the store, these will be passed to the backend implementation. Ignored otherwise.

• **kwargs (Any, default: {} ) –

  Additional parameters are passed through to zarr.creation.open_array or open_group.

Returns:

• z ( array or group ) –

  Return type depends on what exists in the given store.

Source code in zarr/api/synchronous.py

def open(
    store: StoreLike | None = None,
    *,
    mode: AccessModeLiteral | None = None,
    zarr_version: ZarrFormat | None = None,  # deprecated
    zarr_format: ZarrFormat | None = None,
    path: str | None = None,
    storage_options: dict[str, Any] | None = None,
    **kwargs: Any,  # TODO: type kwargs as valid args to async_api.open
) -> Array | Group:
    """Open a group or array using file-mode-like semantics.

    Parameters
    ----------
    store : StoreLike or None, default=None
        Store or path to directory in file system or name of zip file.
    mode : {'r', 'r+', 'a', 'w', 'w-'}, optional
        Persistence mode: 'r' means read only (must exist); 'r+' means
        read/write (must exist); 'a' means read/write (create if doesn't
        exist); 'w' means create (overwrite if exists); 'w-' means create
        (fail if exists).
        If the store is read-only, the default is 'r'; otherwise, it is 'a'.
    zarr_format : {2, 3, None}, optional
        The zarr format to use when saving.
    path : str or None, optional
        The path within the store to open.
    storage_options : dict
        If using an fsspec URL to create the store, these will be passed to
        the backend implementation. Ignored otherwise.
    **kwargs
        Additional parameters are passed through to [`zarr.creation.open_array`][] or
        [`open_group`][zarr.api.asynchronous.open_group].

    Returns
    -------
    z : array or group
        Return type depends on what exists in the given store.
    """
    obj = sync(
        async_api.open(
            store=store,
            mode=mode,
            zarr_version=zarr_version,
            zarr_format=zarr_format,
            path=path,
            storage_options=storage_options,
            **kwargs,
        )
    )
    if isinstance(obj, AsyncArray):
        return Array(obj)
    else:
        return Group(obj)

zarr.open_array

open_array(
    store: StoreLike | None = None,
    *,
    zarr_version: ZarrFormat | None = None,
    zarr_format: ZarrFormat | None = None,
    path: PathLike = "",
    storage_options: dict[str, Any] | None = None,
    **kwargs: Any,
) -> Array

Open an array using file-mode-like semantics.

Parameters:

• store (StoreLike, default: None ) –

  Store or path to directory in file system or name of zip file.

• zarr_version ((2, 3, None), default: 2 ) –

  The zarr format to use when saving. Deprecated in favor of zarr_format.

• zarr_format ((2, 3, None), default: 2 ) –

  The zarr format to use when saving.

• path (str, default: '' ) –

  Path in store to array.

• storage_options (dict, default: None ) –

  If using an fsspec URL to create the store, these will be passed to the backend implementation. Ignored otherwise.

• **kwargs (Any, default: {} ) –

  Any keyword arguments to pass to create.

Returns:

• AsyncArray –

  The opened array.

Source code in zarr/api/synchronous.py

def open_array(
    store: StoreLike | None = None,
    *,
    zarr_version: ZarrFormat | None = None,
    zarr_format: ZarrFormat | None = None,
    path: PathLike = "",
    storage_options: dict[str, Any] | None = None,
    **kwargs: Any,
) -> Array:
    """Open an array using file-mode-like semantics.

    Parameters
    ----------
    store : StoreLike
        Store or path to directory in file system or name of zip file.
    zarr_version : {2, 3, None}, optional
        The zarr format to use when saving. Deprecated in favor of zarr_format.
    zarr_format : {2, 3, None}, optional
        The zarr format to use when saving.
    path : str, optional
        Path in store to array.
    storage_options : dict
        If using an fsspec URL to create the store, these will be passed to
        the backend implementation. Ignored otherwise.
    **kwargs
        Any keyword arguments to pass to [`create`][zarr.api.asynchronous.create].


    Returns
    -------
    AsyncArray
        The opened array.
    """
    return Array(
        sync(
            async_api.open_array(
                store=store,
                zarr_version=zarr_version,
                zarr_format=zarr_format,
                path=path,
                storage_options=storage_options,
                **kwargs,
            )
        )
    )

zarr.open_consolidated

open_consolidated(
    *args: Any,
    use_consolidated: Literal[True] = True,
    **kwargs: Any,
) -> Group

Alias for open_group with use_consolidated=True.

Source code in zarr/api/synchronous.py

def open_consolidated(*args: Any, use_consolidated: Literal[True] = True, **kwargs: Any) -> Group:
    """
    Alias for [`open_group`][zarr.api.synchronous.open_group] with ``use_consolidated=True``.
    """
    return Group(
        sync(async_api.open_consolidated(*args, use_consolidated=use_consolidated, **kwargs))
    )

zarr.open_group

open_group(
    store: StoreLike | None = None,
    *,
    mode: AccessModeLiteral = "a",
    cache_attrs: bool | None = None,
    synchronizer: Any = None,
    path: str | None = None,
    chunk_store: StoreLike | None = None,
    storage_options: dict[str, Any] | None = None,
    zarr_version: ZarrFormat | None = None,
    zarr_format: ZarrFormat | None = None,
    meta_array: Any | None = None,
    attributes: dict[str, JSON] | None = None,
    use_consolidated: bool | str | None = None,
) -> Group

Open a group using file-mode-like semantics.

Parameters:

• store (StoreLike or None, default: None ) –

  Store or path to directory in file system or name of zip file.

  Strings are interpreted as paths on the local file system and used as the root argument to zarr.storage.LocalStore.

  Dictionaries are used as the store_dict argument in zarr.storage.MemoryStore.

  By default (store=None) a new zarr.storage.MemoryStore is created.

• mode (('r', 'r+', 'a', 'w', 'w-'), default: 'r' ) –

  Persistence mode: 'r' means read only (must exist); 'r+' means read/write (must exist); 'a' means read/write (create if doesn't exist); 'w' means create (overwrite if exists); 'w-' means create (fail if exists).

• cache_attrs (bool, default: None ) –

  If True (default), user attributes will be cached for attribute read operations. If False, user attributes are reloaded from the store prior to all attribute read operations.

• synchronizer (object, default: None ) –

  Array synchronizer.

• path (str, default: None ) –

  Group path within store.

• chunk_store (StoreLike or None, default: None ) –

  Store or path to directory in file system or name of zip file.

• storage_options (dict, default: None ) –

  If using an fsspec URL to create the store, these will be passed to the backend implementation. Ignored otherwise.

• meta_array (array - like, default: None ) –

  An array instance to use for determining arrays to create and return to users. Use numpy.empty(()) by default.

• attributes (dict, default: None ) –

  A dictionary of JSON-serializable values with user-defined attributes.

• use_consolidated (bool or str, default: None ) –

  Whether to use consolidated metadata.

  By default, consolidated metadata is used if it's present in the store (in the zarr.json for Zarr format 3 and in the .zmetadata file for Zarr format 2).

  To explicitly require consolidated metadata, set use_consolidated=True, which will raise an exception if consolidated metadata is not found.

  To explicitly not use consolidated metadata, set use_consolidated=False, which will fall back to using the regular, non consolidated metadata.

  Zarr format 2 allowed configuring the key storing the consolidated metadata (.zmetadata by default). Specify the custom key as use_consolidated to load consolidated metadata from a non-default key.

Returns:

• g ( Group ) –

  The new group.

Source code in zarr/api/synchronous.py

def open_group(
    store: StoreLike | None = None,
    *,
    mode: AccessModeLiteral = "a",
    cache_attrs: bool | None = None,  # default changed, not used in async api
    synchronizer: Any = None,  # not used in async api
    path: str | None = None,
    chunk_store: StoreLike | None = None,  # not used in async api
    storage_options: dict[str, Any] | None = None,  # not used in async api
    zarr_version: ZarrFormat | None = None,  # deprecated
    zarr_format: ZarrFormat | None = None,
    meta_array: Any | None = None,  # not used in async api
    attributes: dict[str, JSON] | None = None,
    use_consolidated: bool | str | None = None,
) -> Group:
    """Open a group using file-mode-like semantics.

    Parameters
    ----------
    store : StoreLike or None, default=None
        Store or path to directory in file system or name of zip file.

        Strings are interpreted as paths on the local file system
        and used as the ``root`` argument to [zarr.storage.LocalStore][].

        Dictionaries are used as the ``store_dict`` argument in
        [zarr.storage.MemoryStore][].

        By default (``store=None``) a new [zarr.storage.MemoryStore][]
        is created.

    mode : {'r', 'r+', 'a', 'w', 'w-'}, optional
        Persistence mode: 'r' means read only (must exist); 'r+' means
        read/write (must exist); 'a' means read/write (create if doesn't
        exist); 'w' means create (overwrite if exists); 'w-' means create
        (fail if exists).
    cache_attrs : bool, optional
        If True (default), user attributes will be cached for attribute read
        operations. If False, user attributes are reloaded from the store prior
        to all attribute read operations.
    synchronizer : object, optional
        Array synchronizer.
    path : str, optional
        Group path within store.
    chunk_store : StoreLike or None, default=None
        Store or path to directory in file system or name of zip file.
    storage_options : dict
        If using an fsspec URL to create the store, these will be passed to
        the backend implementation. Ignored otherwise.
    meta_array : array-like, optional
        An array instance to use for determining arrays to create and return
        to users. Use `numpy.empty(())` by default.
    attributes : dict
        A dictionary of JSON-serializable values with user-defined attributes.
    use_consolidated : bool or str, default None
        Whether to use consolidated metadata.

        By default, consolidated metadata is used if it's present in the
        store (in the ``zarr.json`` for Zarr format 3 and in the ``.zmetadata`` file
        for Zarr format 2).

        To explicitly require consolidated metadata, set ``use_consolidated=True``,
        which will raise an exception if consolidated metadata is not found.

        To explicitly *not* use consolidated metadata, set ``use_consolidated=False``,
        which will fall back to using the regular, non consolidated metadata.

        Zarr format 2 allowed configuring the key storing the consolidated metadata
        (``.zmetadata`` by default). Specify the custom key as ``use_consolidated``
        to load consolidated metadata from a non-default key.

    Returns
    -------
    g : Group
        The new group.
    """
    return Group(
        sync(
            async_api.open_group(
                store=store,
                mode=mode,
                cache_attrs=cache_attrs,
                synchronizer=synchronizer,
                path=path,
                chunk_store=chunk_store,
                storage_options=storage_options,
                zarr_version=zarr_version,
                zarr_format=zarr_format,
                meta_array=meta_array,
                attributes=attributes,
                use_consolidated=use_consolidated,
            )
        )
    )

zarr.open_like

open_like(a: ArrayLike, path: str, **kwargs: Any) -> Array

Open a persistent array like another array.

Parameters:

• a (Array) –

  The shape and data-type of a define these same attributes of the returned array.

• path (str) –

  The path to the new array.

• **kwargs (Any, default: {} ) –

  Any keyword arguments to pass to the array constructor.

Returns:

• AsyncArray –

  The opened array.

Source code in zarr/api/synchronous.py

def open_like(a: ArrayLike, path: str, **kwargs: Any) -> Array:
    """Open a persistent array like another array.

    Parameters
    ----------
    a : Array
        The shape and data-type of a define these same attributes of the returned array.
    path : str
        The path to the new array.
    **kwargs
        Any keyword arguments to pass to the array constructor.

    Returns
    -------
    AsyncArray
        The opened array.
    """
    return Array(sync(async_api.open_like(a, path=path, **kwargs)))