Method __init__

xarray/backends/scipy_.py:222–278

(
        self,
        filename_or_obj: T_PathFileOrDataStore,
        mode: Literal["r", "w", "a"] = "r",
        format: str | None = None,
        group: str | None = None,
        mmap: bool | None = None,
        lock: Lock | Literal[False] | None = None,
    )

    _manager: FileManager[scipy.io.netcdf_file]

    def __init__(
        self,
        filename_or_obj: T_PathFileOrDataStore,
        mode: Literal["r", "w", "a"] = "r",
        format: str | None = None,
        group: str | None = None,
        mmap: bool | None = None,
        lock: Lock | Literal[False] | None = None,
    ) -> None:
        if group is not None:
            raise ValueError("cannot save to a group with the scipy.io.netcdf backend")

        version: Literal[1, 2]
        if format is None or format == "NETCDF3_64BIT":
            version = 2
        elif format == "NETCDF3_CLASSIC":
            version = 1
        else:
            raise ValueError(f"invalid format for scipy.io.netcdf backend: {format!r}")

        if lock is None and mode != "r" and isinstance(filename_or_obj, str):
            lock = get_write_lock(filename_or_obj)

        self.lock = ensure_lock(lock)

        if isinstance(filename_or_obj, BytesIOProxy):
            source = filename_or_obj
            filename_or_obj = io.BytesIO()
            source.getvalue = filename_or_obj.getbuffer

        manager: FileManager
        if isinstance(filename_or_obj, str):  # path
            manager = CachingFileManager(
                _open_scipy_netcdf,
                filename_or_obj,
                mode=mode,
                lock=lock,
                kwargs=dict(mmap=mmap, version=version),
            )
        elif hasattr(filename_or_obj, "seek"):  # file object
            # Note: checking for .seek matches the check for file objects
            # in scipy.io.netcdf_file
            scipy_dataset = _open_scipy_netcdf(
                filename_or_obj,  # type: ignore[arg-type]  # unsupported cases are caught above
                mode=mode,
                mmap=mmap,
                version=version,
                flush_only=True,
            )
            assert not scipy_dataset.use_mmap  # no mmap for file objects
            manager = DummyFileManager(scipy_dataset)
        else:
            raise ValueError(
                f"cannot open {filename_or_obj=} with scipy.io.netcdf_file"
            )

        self._manager = manager