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Core Module / コアモジュール

The wandas.core module provides the foundation components of the Wandas library. wandas.core モジュールは、Wandasライブラリの基盤となるコンポーネントを提供します。

BaseFrame

BaseFrame is the base class for all Wandas frames. It defines the basic data structure and operations. BaseFrameはすべてのWandasフレームの基底クラスです。これは基本的なデータ構造と操作を定義します。

wandas.core.base_frame.BaseFrame

Bases: ABC, Generic[T]

Abstract base class for all signal frame types.

This class provides the common interface and functionality for all frame types used in signal processing. It implements basic operations like indexing, iteration, and data manipulation that are shared across all frame types.

Parameters

data : DaArray The signal data to process. Must be a dask array. sampling_rate : float The sampling rate of the signal in Hz. label : str, optional A label for the frame. If not provided, defaults to "unnamed_frame". metadata : dict, optional Additional metadata for the frame. lineage : LineageNode, optional Constructor override for the initial runtime lineage. When omitted, the constructor creates a source node; every constructed frame therefore has exactly one lineage authority. operation_history is its public JSON-safe projection. channel_metadata : list[ChannelMetadata | dict], optional Metadata for each channel in the frame. Can be ChannelMetadata objects or dicts that will be converted to ChannelMetadata objects. previous : BaseFrame, optional Compatibility/debug pointer to the immediate prior frame. This strong reference is not the source of truth for processing history.

Attributes

sampling_rate : float The sampling rate of the signal in Hz. label : str The label of the frame. metadata : dict Additional metadata for the frame. lineage : LineageNode Runtime computation lineage. This is always set during construction and propagated through _create_new_instance. operation_history : list[dict] Flat read-only compatibility view derived from lineage.

Source code in wandas/core/base_frame.py
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class BaseFrame(ABC, Generic[T]):
    """
    Abstract base class for all signal frame types.

    This class provides the common interface and functionality for all frame types
    used in signal processing. It implements basic operations like indexing, iteration,
    and data manipulation that are shared across all frame types.

    Parameters
    ----------
    data : DaArray
        The signal data to process. Must be a dask array.
    sampling_rate : float
        The sampling rate of the signal in Hz.
    label : str, optional
        A label for the frame. If not provided, defaults to "unnamed_frame".
    metadata : dict, optional
        Additional metadata for the frame.
    lineage : LineageNode, optional
        Constructor override for the initial runtime lineage. When omitted, the
        constructor creates a source node; every constructed frame therefore has
        exactly one lineage authority. ``operation_history`` is its public JSON-safe
        projection.
    channel_metadata : list[ChannelMetadata | dict], optional
        Metadata for each channel in the frame. Can be ChannelMetadata objects
        or dicts that will be converted to ChannelMetadata objects.
    previous : BaseFrame, optional
        Compatibility/debug pointer to the immediate prior frame. This strong
        reference is not the source of truth for processing history.

    Attributes
    ----------
    sampling_rate : float
        The sampling rate of the signal in Hz.
    label : str
        The label of the frame.
    metadata : dict
        Additional metadata for the frame.
    lineage : LineageNode
        Runtime computation lineage. This is always set during construction and
        propagated through ``_create_new_instance``.
    operation_history : list[dict]
        Flat read-only compatibility view derived from ``lineage``.
    """

    _CHANNEL_DIM: ClassVar[str] = "channel"
    # Fallback only for neutral-dim and legacy frames. Target frames should
    # prefer the xarray "channel" dimension when it is declared.
    _channel_axis: ClassVar[int | None] = -2
    _xarray_dim_suffix: ClassVar[tuple[str, ...]] = ()
    _array_ufunc_reverse_methods: ClassVar[Mapping[str, str]] = {
        "add": "__radd__",
        "subtract": "__rsub__",
        "multiply": "__rmul__",
        "divide": "__rtruediv__",
        "true_divide": "__rtruediv__",
        "power": "__rpow__",
    }
    _xr: xr.DataArray
    _previous: "BaseFrame[Any] | None"

    def __init__(
        self,
        data: DaArray,
        sampling_rate: float,
        label: str | None = None,
        metadata: dict[str, Any] | None = None,
        channel_metadata: Sequence[ChannelMetadata | dict[str, Any]] | None = None,
        channel_ids: list[str] | None = None,
        previous: "BaseFrame[Any] | None" = None,
        source_time_offset: float | Sequence[float] | NDArrayReal = 0.0,
        lineage: LineageNode | None = None,
        operation_history_prefix: Sequence[Mapping[str, Any]] = (),
    ):
        """Initialize immutable Frame data, metadata, channel state, and lineage."""
        normalized_sampling_rate = _normalize_sampling_rate(sampling_rate)
        self._pending_sampling_rate = normalized_sampling_rate
        normalized_data = self._normalize_data(data)
        frame_label = _normalize_frame_label(label)
        channel_count = self._channel_size_from_xarray_dims(normalized_data)
        if channel_count is None:
            channel_count = self._channel_count_from_data(normalized_data)

        normalized_channel_metadata = self._normalize_channel_metadata_for_count(channel_metadata, channel_count)
        self._pending_channel_metadata = normalized_channel_metadata
        self._pending_channel_ids = (
            self._validate_channel_ids(channel_ids, channel_count)
            if channel_ids is not None
            else self._default_channel_ids(channel_count)
        )

        self._xr = self._build_xarray(normalized_data, name=frame_label)
        self._write_label(label)
        self._write_normalized_sampling_rate(normalized_sampling_rate)
        self._write_metadata(metadata)
        if lineage is not None and operation_history_prefix:
            raise ValueError("operation_history_prefix is valid only for a new source Frame")
        self._lineage = lineage if lineage is not None else source_lineage(operation_history_prefix)
        self._write_normalized_channel_metadata(normalized_channel_metadata, self._pending_channel_ids)
        self._write_source_time_offset(source_time_offset)
        del self._pending_channel_metadata
        del self._pending_channel_ids
        del self._pending_sampling_rate
        self._previous = previous

        try:
            # Display information for newer dask versions
            effective_data = self._effective_data
            logger.debug(f"Dask graph layers: {list(effective_data.dask.layers.keys())}")
            logger.debug(f"Dask graph dependencies: {len(effective_data.dask.dependencies)}")
        except Exception as e:
            logger.debug(f"Dask graph visualization details unavailable: {e}")

    @property
    def _data(self) -> DaArray:
        """Compatibility alias for the Dask array stored in ``_xr``."""
        data = self._xr.data
        if not isinstance(data, DaArray):
            raise TypeError(f"Internal xarray data is not a Dask array: {type(data).__name__}")
        return data

    @property
    def _effective_data(self) -> DaArray:
        """Return lazily calibrated data used by numerical public APIs."""
        factors = tuple(channel.calibration.factor for channel in self.channels)
        if all(factor == 1.0 for factor in factors):
            return self._data
        return apply_channel_factors(self._data, factors)

    def _replace_data(self, data: DaArray) -> None:
        """Replace the internal xarray data container without touching frame state."""
        old_channel_metadata = self.channels.to_list()
        old_channel_ids = self._channel_ids
        old_source_time_offset = self.source_time_offset
        normalized = self._normalize_data(data)
        attrs = copy.deepcopy(self._xr.attrs)
        self._xr = self._build_xarray(normalized, name=self.label)
        self._xr.attrs = attrs
        if len(old_channel_metadata) == self._n_channels and len(old_channel_ids) == self._n_channels:
            self._write_normalized_channel_metadata(old_channel_metadata, old_channel_ids)
            self._write_source_time_offset(old_source_time_offset)

    def _normalize_data(self, data: DaArray) -> DaArray:
        """Normalize Dask data shape and chunks using Wandas channel-wise policy."""
        try:
            normalized = data.reshape((1, -1)) if data.ndim == 1 else data
            if normalized.ndim >= 2:
                chunks = tuple([1] + [-1] * (normalized.ndim - 1))
            else:
                chunks = tuple([-1] * normalized.ndim)
            return normalized.rechunk(chunks)
        except Exception as e:
            logger.warning(f"Rechunk failed: {e!r}. Falling back to chunks=-1.")
            return data.rechunk(chunks=-1)

    def _build_xarray(self, data: DaArray, *, name: str) -> xr.DataArray:
        """Build the internal xarray container for frame data, dims, and coords."""
        return xr.DataArray(
            data,
            dims=self._xarray_dims(data),
            coords=self._xarray_coords(data),
            name=name,
        )

    def _xarray_dims(self, data: DaArray) -> tuple[str, ...]:
        """Return semantic xarray dims only for exact suffix-shaped data."""
        suffix = self._xarray_dim_suffix
        if suffix and data.ndim == len(suffix):
            return suffix
        return tuple(f"dim_{i}" for i in range(data.ndim))

    def _xarray_coords(self, data: DaArray) -> dict[str, Any]:
        """Return conservative coordinates for declared xarray dimensions."""
        channel_size = self._channel_size_from_xarray_dims(data)
        if channel_size is None:
            return {}

        metadata = getattr(self, "_pending_channel_metadata", None)
        channel_ids = getattr(self, "_pending_channel_ids", None)
        if metadata is None or channel_ids is None or len(metadata) != channel_size:
            return {}
        return {
            self._CHANNEL_DIM: (self._CHANNEL_DIM, channel_ids),
            _CHANNEL_LABEL_KEY: (self._CHANNEL_DIM, [ch.label for ch in metadata]),
            _CHANNEL_UNIT_KEY: (self._CHANNEL_DIM, [ch.unit for ch in metadata]),
            _CHANNEL_REF_KEY: (self._CHANNEL_DIM, [ch.ref for ch in metadata]),
            _CHANNEL_CALIBRATION_FACTOR_KEY: (
                self._CHANNEL_DIM,
                [ch.calibration.factor for ch in metadata],
            ),
        }

    def _channel_size_from_xarray_dims(self, data: DaArray) -> int | None:
        """Return the channel size implied by xarray dims, if present."""
        dims = self._xarray_dims(data)
        if self._CHANNEL_DIM not in dims:
            return None
        return int(data.shape[dims.index(self._CHANNEL_DIM)])

    def _channel_count_from_data(self, data: DaArray) -> int:
        """Return the frame channel count from the declared channel axis."""
        if self._channel_axis is None:
            return 1
        return int(data.shape[self._channel_axis])

    @property
    def _n_channels(self) -> int:
        """Returns the number of channels from the xarray channel dimension when available."""
        if self._CHANNEL_DIM in self._xr.sizes:
            return int(self._xr.sizes[self._CHANNEL_DIM])
        return self._channel_count_from_data(self._data)

    @staticmethod
    def _default_channel_ids(n_channels: int) -> list[str]:
        """Return deterministic source channel identifiers."""
        return [f"c{i}" for i in range(n_channels)]

    @staticmethod
    def _validate_channel_ids(channel_ids: Sequence[Any], n_channels: int) -> list[str]:
        """Normalize unique channel identifiers and enforce channel-count agreement."""
        return _normalize_channel_ids(channel_ids, expected_count=n_channels)

    def _normalize_channel_metadata_for_count(
        self,
        channel_metadata: Sequence[ChannelMetadata | dict[str, Any]] | None,
        channel_count: int,
    ) -> list[ChannelMetadata]:
        """Return defensive metadata values matching an exact channel count."""

        def _to_channel_metadata(ch: ChannelMetadata | dict[str, Any], index: int) -> ChannelMetadata:
            """Decode one metadata-like value with index-aware errors."""
            if type(ch) is ChannelMetadataView:
                return ch.to_metadata()
            if isinstance(ch, ChannelMetadata):
                return copy.deepcopy(ch)
            if isinstance(ch, dict):
                try:
                    return ChannelMetadata(**ch)
                except (TypeError, ValueError) as e:
                    raise ValueError(
                        f"Invalid channel_metadata at index {index}\n"
                        f"  Got: {ch}\n"
                        f"  Error: {e}\n"
                        f"Ensure all dict keys match ChannelMetadata fields "
                        f"(label, unit, ref, extra) and have correct types."
                    ) from e
            raise TypeError(
                f"Invalid type in channel_metadata at index {index}\n"
                f"  Got: {type(ch).__name__} ({ch!r})\n"
                f"  Expected: ChannelMetadata or dict\n"
                f"Use ChannelMetadata objects or dicts with valid fields."
            )

        if channel_metadata is None:
            result = [ChannelMetadata(label=f"ch{i}", unit="", extra={}) for i in range(channel_count)]
        else:
            result = [_to_channel_metadata(ch, i) for i, ch in enumerate(channel_metadata)]
        if len(result) > channel_count:
            raise ValueError(
                "Channel metadata length must not exceed number of channels\n"
                f"  Metadata entries: {len(result)}\n"
                f"  Channels: {channel_count}"
            )
        if len(result) < channel_count:
            result.extend(ChannelMetadata(label=f"ch{i}", unit="", extra={}) for i in range(len(result), channel_count))
        return result

    def _refresh_xarray_channel_coord(self) -> None:
        """Refresh auxiliary channel metadata coordinates after compatibility mutations."""
        self._set_channel_metadata(list(self.channels), self._channel_ids)

    @property
    def _channel_ids(self) -> list[str]:
        """Return channel identifiers from xarray coordinates or legacy attrs."""
        if self._CHANNEL_DIM in self._xr.coords:
            return _normalize_channel_ids(self._xr.coords[self._CHANNEL_DIM].values.tolist())
        return _normalize_channel_ids(self._xr.attrs.get(_CHANNEL_IDS_ATTR, []))

    def _channel_id_at(self, index: int) -> str:
        """Return the stable identifier for one channel position."""
        if self._CHANNEL_DIM in self._xr.coords:
            value = self._xr.coords[self._CHANNEL_DIM].values[index]
        else:
            value = self._xr.attrs[_CHANNEL_IDS_ATTR][index]
        return _normalize_channel_ids([value], expected_count=1)[0]

    def _get_channel_coord_value(self, coord_name: str, index: int) -> Any:
        """Read one channel metadata value from coordinates or legacy attrs."""
        if coord_name in self._xr.coords:
            return self._xr.coords[coord_name].values[index]
        return self._xr.attrs[coord_name][index]

    def _channel_ids_for_selection(self, indices: Sequence[int]) -> list[str]:
        """Return collision-free stable identifiers for a channel selection."""
        selected_ids: list[str] = []
        used_ids: set[str] = set()
        for index in indices:
            channel_id = self._channel_id_at(index)
            if channel_id in used_ids:
                channel_id = self._next_channel_id([*self._channel_ids, *selected_ids])
            selected_ids.append(channel_id)
            used_ids.add(channel_id)
        return selected_ids

    @property
    def channels(self) -> ChannelMetadataIndexer:
        """Property to access channel metadata."""
        return ChannelMetadataIndexer(self)

    def _borrowed_channel_metadata_descriptors(
        self,
        indices: Sequence[int] | None = None,
        *,
        calibrations: Mapping[str, ChannelCalibration] | None = None,
    ) -> list[dict[str, Any]]:
        """Describe channel state for immediate ownership by a Frame constructor.

        The returned ``extra`` dictionaries remain owned by this Frame. Callers must
        pass the descriptors directly to a Frame constructor, whose normalization
        boundary takes one defensive copy.
        """
        selected = range(self.n_channels) if indices is None else indices
        descriptors: list[dict[str, Any]] = []
        for index in selected:
            channel_id = self._channel_id_at(index)
            calibration = (
                calibrations[channel_id]
                if calibrations is not None and channel_id in calibrations
                else self.channels[index].calibration
            )
            descriptors.append(
                {
                    "label": self.channels[index].label,
                    "calibration": calibration,
                    "extra": self._channel_extra_at(index),
                }
            )
        return descriptors

    def _channel_extra_at(self, index: int) -> Mapping[str, Any]:
        """Borrow one internal channel-extra mapping for immediate reconstruction."""
        values = self._xr.attrs.get(_CHANNEL_EXTRA_ATTR, {})
        value = values.get(self._channel_id_at(index), {}) if isinstance(values, Mapping) else {}
        return value if isinstance(value, Mapping) else {}

    @property
    def _channel_metadata(self) -> list[ChannelMetadata]:
        """Compatibility list-like view over xarray-backed channel metadata."""
        return cast(list[ChannelMetadata], self.channels)

    @_channel_metadata.setter
    def _channel_metadata(self, value: Sequence[ChannelMetadata | dict[str, Any]]) -> None:
        """Replace the compatibility metadata view through xarray-backed state."""
        self._set_channel_metadata(value)

    def _set_channel_coord_value(self, coord_name: str, index: int, value: Any) -> None:
        """Update one xarray-backed channel metadata coordinate defensively."""
        if coord_name == _CHANNEL_LABEL_KEY:
            value = _normalize_channel_label(value)
        elif coord_name in {
            _CHANNEL_CALIBRATION_FACTOR_KEY,
            _CHANNEL_UNIT_KEY,
            _CHANNEL_REF_KEY,
        }:
            raise RuntimeError("Calibration coordinates must be written atomically with _set_channel_calibration")
        if coord_name in self._xr.coords:
            values = self._xr.coords[coord_name].values.tolist()
            values[index] = value
            self._xr = self._xr.assign_coords({coord_name: (self._CHANNEL_DIM, values)})
            return
        values = list(self._xr.attrs.get(coord_name, []))
        values[index] = value
        self._xr.attrs[coord_name] = values

    def _set_channel_calibration(self, index: int, calibration: ChannelCalibration) -> None:
        """Atomically replace one channel's factor and physical-domain coordinates."""
        if not isinstance(calibration, ChannelCalibration):
            raise TypeError("calibration must be a ChannelCalibration")
        updates = {
            _CHANNEL_CALIBRATION_FACTOR_KEY: calibration.factor,
            _CHANNEL_UNIT_KEY: calibration.unit,
            _CHANNEL_REF_KEY: calibration.ref,
        }
        if self._CHANNEL_DIM in self._xr.dims:
            coords: dict[str, Any] = {}
            for name, value in updates.items():
                values = self._xr.coords[name].values.tolist()
                values[index] = value
                coords[name] = (self._CHANNEL_DIM, values)
            self._xr = self._xr.assign_coords(coords)
            return
        for name, value in updates.items():
            values = list(self._xr.attrs[name])
            values[index] = value
            self._xr.attrs[name] = values

    def _set_channel_metadata(
        self,
        channel_metadata: Sequence[ChannelMetadata | dict[str, Any]],
        channel_ids: Sequence[Any] | None = None,
    ) -> None:
        """Take ownership of metadata-like values and write synchronized storage."""
        normalized = self._normalize_channel_metadata_for_count(channel_metadata, self._n_channels)
        self._write_normalized_channel_metadata(normalized, channel_ids)

    def _write_normalized_channel_metadata(
        self,
        channel_metadata: Sequence[ChannelMetadata],
        channel_ids: Sequence[Any] | None = None,
    ) -> None:
        """Write exclusively owned, normalized channel metadata without copying."""
        ids = (
            self._validate_channel_ids(channel_ids, self._n_channels) if channel_ids is not None else self._channel_ids
        )
        if not ids:
            ids = self._default_channel_ids(self._n_channels)
        if len(channel_metadata) != self._n_channels:
            raise ValueError(
                "Normalized channel metadata length must match number of channels\n"
                f"  Metadata entries: {len(channel_metadata)}\n"
                f"  Channels: {self._n_channels}"
            )
        labels = [_normalize_channel_label(ch.label) for ch in channel_metadata]
        units = [ch.unit for ch in channel_metadata]
        refs = [ch.ref for ch in channel_metadata]
        factors = [ch.calibration.factor for ch in channel_metadata]
        channel_extra = {channel_id: ch.extra for channel_id, ch in zip(ids, channel_metadata, strict=True)}
        self._xr.attrs[_CHANNEL_EXTRA_ATTR] = channel_extra
        if self._CHANNEL_DIM in self._xr.dims:
            self._xr = self._xr.assign_coords(
                {
                    self._CHANNEL_DIM: (self._CHANNEL_DIM, ids),
                    _CHANNEL_LABEL_KEY: (self._CHANNEL_DIM, labels),
                    _CHANNEL_UNIT_KEY: (self._CHANNEL_DIM, units),
                    _CHANNEL_REF_KEY: (self._CHANNEL_DIM, refs),
                    _CHANNEL_CALIBRATION_FACTOR_KEY: (self._CHANNEL_DIM, factors),
                }
            )
            for name in _CHANNEL_COORD_FALLBACK_ATTRS:
                self._xr.attrs.pop(name, None)
            return
        self._xr.attrs.update(
            {
                _CHANNEL_IDS_ATTR: ids,
                _CHANNEL_LABEL_KEY: labels,
                _CHANNEL_UNIT_KEY: units,
                _CHANNEL_REF_KEY: refs,
                _CHANNEL_CALIBRATION_FACTOR_KEY: factors,
            }
        )

    def _next_channel_id(self, existing_ids: Sequence[str] | None = None) -> str:
        """Return the first unused deterministic channel identifier."""
        ids = set(existing_ids if existing_ids is not None else self._channel_ids)
        index = 0
        while f"c{index}" in ids:
            index += 1
        return f"c{index}"

    @property
    def n_channels(self) -> int:
        """Returns the number of channels."""
        return self._n_channels

    @property
    def previous(self) -> "BaseFrame[Any] | None":
        """Return the immediate prior frame for compatibility/debug inspection.

        This strong reference is not the source of truth for processing
        history. Runtime lineage drives ``operation_history`` and Recipe extraction.
        """
        return self._previous

    @property
    def sampling_rate(self) -> float:
        """Return the frame sampling rate from xarray attrs."""
        return float(self._xr.attrs["sampling_rate"])

    def _write_sampling_rate(self, value: float) -> None:
        self._write_normalized_sampling_rate(_normalize_sampling_rate(value))

    def _write_normalized_sampling_rate(self, value: float) -> None:
        """Store a sampling rate already validated in its binary64 representation."""
        self._xr.attrs["sampling_rate"] = value

    @property
    def label(self) -> str:
        """Return the frame label from xarray attrs."""
        value = self._xr.attrs.get("label", self._xr.name)
        return _normalize_frame_label(value)

    def _write_label(self, value: str | None) -> None:
        label = _normalize_frame_label(value)
        self._xr.attrs["label"] = label
        self._xr.name = label

    @property
    def metadata(self) -> dict[str, Any]:
        """Return an owned snapshot of frame metadata."""
        value = self._xr.attrs.get("metadata")
        if value is None:
            return {}
        if not isinstance(value, dict):
            raise TypeError(f"Internal metadata attrs must be a dictionary, got {type(value).__name__}")
        return copy.deepcopy(value)

    def _write_metadata(self, value: dict[str, Any] | None) -> None:
        self._xr.attrs["metadata"] = _snapshot_frame_metadata(value, none_as_empty=True)

    @property
    def operation_history(self) -> list[dict[str, Any]]:
        """Return the sole public, JSON-safe provenance projection."""
        return lineage_history(self._lineage)

    @property
    def lineage(self) -> LineageNode:
        """Return runtime computation lineage for this frame."""
        return self._lineage

    def _required_semantic_lineage(self) -> LineageNode:
        """Return the active authoritative lineage or reject an internal bypass."""
        lineage = active_semantic_lineage()
        if not isinstance(lineage, LineageNode):
            raise RuntimeError("Public semantic lineage capture is not active")
        return lineage

    def _semantic_index_params(self, key: Any) -> Mapping[str, Any]:
        """Encode one public index as portable selector intent when supported."""
        if isinstance(key, tuple) and len(key) == 1:
            key = key[0]
        if isinstance(key, numbers.Integral) and not isinstance(key, bool | np.bool_):
            return {"indexing": "integer", "index": int(key)}
        if isinstance(key, str):
            return {"indexing": "label", "label": key}
        if isinstance(key, slice):
            bounds = self._slice_for_lineage(key)
            return {"indexing": "unsupported"} if bounds is None else {"indexing": "channel_slice", **bounds}
        if isinstance(key, np.ndarray) and key.ndim == 1 and key.dtype in (bool, np.bool_):
            return {"indexing": "boolean_mask", "mask": tuple(bool(value) for value in key.tolist())}
        if isinstance(key, np.ndarray) and key.ndim == 1 and np.issubdtype(key.dtype, np.integer):
            return {"indexing": "integer_array", "indices": tuple(int(value) for value in key.tolist())}
        if isinstance(key, list) and key and all(isinstance(value, str) for value in key):
            return {"indexing": "label_list", "labels": tuple(key)}
        if (
            isinstance(key, list)
            and key
            and all(isinstance(value, numbers.Integral) and not isinstance(value, bool | np.bool_) for value in key)
        ):
            return {"indexing": "integer_list", "indices": tuple(int(value) for value in key)}
        if isinstance(key, tuple) and key:
            channel = self._channel_selector_for_lineage(key[0])
            axis_slices = self._axis_slices_for_lineage(key[1:])
            if channel is not None and axis_slices is not None:
                return {"indexing": "multidimensional_slice", "channel": channel, "axis_slices": axis_slices}
            return {"indexing": "multidimensional"}
        return {"indexing": "unsupported"}

    @staticmethod
    def _slice_from_intent(value: Mapping[str, Any]) -> slice:
        """Decode canonical slice bounds into a fresh Python slice."""
        return slice(value.get("start"), value.get("stop"), value.get("step"))

    @classmethod
    def _selector_from_intent(cls, value: Mapping[str, Any]) -> Any:
        """Decode canonical channel-selector intent for public Recipe replay."""
        kind = value.get("indexing")
        if kind == "integer":
            return int(value["index"])
        if kind == "label":
            return value["label"]
        if kind == "channel_slice":
            return cls._slice_from_intent(value)
        if kind in {"integer_list", "integer_array"}:
            indices = [int(item) for item in value["indices"]]
            return indices if kind == "integer_list" else np.asarray(indices, dtype=int)
        if kind == "label_list":
            return list(value["labels"])
        if kind == "boolean_mask":
            return np.asarray(value["mask"], dtype=bool)
        if kind == "multidimensional_slice":
            channel = cls._selector_from_intent(cast(Mapping[str, Any], value["channel"]))
            axes = tuple(cls._slice_from_intent(item) for item in value["axis_slices"])
            return (channel, *axes)
        raise TypeError(f"Unsupported canonical selector: {kind!r}")

    def _apply_index_intent(self: S, intent: Mapping[str, Any]) -> S:
        """Apply one already-validated canonical selector."""
        return self[self._selector_from_intent(intent)]

    @staticmethod
    def _slice_bound_for_lineage(value: Any) -> int | None:
        """Normalize an optional integral slice bound for semantic capture."""
        if value is None:
            return None
        if isinstance(value, bool) or not isinstance(value, numbers.Integral):
            return None
        return int(value)

    @classmethod
    def _slice_for_lineage(cls, key: slice) -> dict[str, int | None] | None:
        """Encode a portable integral slice or return ``None`` when unsupported."""
        start = cls._slice_bound_for_lineage(key.start)
        stop = cls._slice_bound_for_lineage(key.stop)
        step = cls._slice_bound_for_lineage(key.step)
        if (key.start is not None and start is None) or (key.stop is not None and stop is None):
            return None
        if key.step is not None and step is None:
            return None
        return {"start": start, "stop": stop, "step": step}

    @classmethod
    def _axis_slices_for_lineage(cls, keys: tuple[Any, ...]) -> tuple[dict[str, int | None], ...] | None:
        """Encode portable non-channel axis slices for multidimensional indexing."""
        axis_slices: list[dict[str, int | None]] = []
        for key in keys:
            if not isinstance(key, slice):
                return None
            axis_slice = cls._slice_for_lineage(key)
            if axis_slice is None:
                return None
            axis_slices.append(axis_slice)
        return tuple(axis_slices)

    @property
    def source_time_offset(self) -> NDArrayReal:
        """Return each channel's offset from local time axis to source time."""
        if "source_time_offset" in self._xr.coords:
            value = self._xr.coords["source_time_offset"].values
        else:
            value = self._xr.attrs.get("source_time_offset", 0.0)
        return self._normalize_source_time_offset(value, self.n_channels)

    def _write_source_time_offset(self, value: float | Sequence[float] | NDArrayReal) -> None:
        offsets = self._normalize_source_time_offset(value, self.n_channels)
        if self._CHANNEL_DIM in self._xr.dims:
            self._xr = self._xr.assign_coords({"source_time_offset": (self._CHANNEL_DIM, offsets)})
            self._xr.attrs.pop("source_time_offset", None)
            return
        self._xr.attrs["source_time_offset"] = offsets

    @staticmethod
    def _normalize_source_time_offset(
        value: object,
        n_channels: int,
    ) -> NDArrayReal:
        """Return a defensive finite per-channel source-time offset array."""
        return _normalize_source_time_offset_value(value, n_channels)

    def with_label(self: S, label: str | None) -> S:
        """Return an annotation-only copy with a replacement Frame label."""
        return self._with_annotations(label=label, label_is_set=True)

    def with_metadata(self: S, updates: Mapping[str, Any], *, replace: bool = False) -> S:
        """Return an annotation-only copy with merged or replaced metadata."""
        _validate_frame_metadata(updates)
        return self._with_annotations(metadata=updates, replace=replace)

    def _resolve_one_channel(self, selector: str | int) -> int:
        if isinstance(selector, bool) or not isinstance(selector, str | int):
            raise TypeError("Channel selector must be a label or integer index")
        if isinstance(selector, int):
            if selector < -self.n_channels or selector >= self.n_channels:
                raise IndexError(f"Channel index out of range: {selector}")
            return selector % self.n_channels
        matches = [index for index, label in enumerate(self.labels) if label == selector]
        if not matches:
            raise KeyError(f"Channel selector not found: {selector!r}")
        if len(matches) > 1:
            raise ValueError(f"Channel label is ambiguous: {selector!r}; use an integer index")
        return matches[0]

    def with_channel_extra(
        self: S,
        channel: str | int,
        updates: Mapping[str, Any],
        *,
        replace: bool = False,
    ) -> S:
        """Return an annotation-only copy with one channel's extra metadata updated."""
        return self._with_annotations(channel_extra={channel: updates}, replace=replace)

    def _with_annotations(
        self: S,
        *,
        label: str | None = None,
        label_is_set: bool = False,
        metadata: Mapping[str, Any] | None = None,
        channel_extra: Mapping[str | int, Mapping[str, Any]] | None = None,
        replace: bool = False,
    ) -> S:
        """Apply normalized annotation intent through one reconstruction engine."""
        if type(replace) is not bool:
            raise TypeError("replace must be a bool")
        normalized_label = _normalize_frame_label(label) if label_is_set else self.label
        normalized_metadata = _validate_frame_metadata(metadata) if metadata is not None else None
        stored_metadata = self._xr.attrs.get("metadata", {})
        new_metadata = (
            {}
            if replace and normalized_metadata is not None
            else dict(_validate_frame_metadata(stored_metadata, none_as_empty=True))
        )
        if normalized_metadata is not None:
            new_metadata.update(normalized_metadata)
        descriptors = self._borrowed_channel_metadata_descriptors()
        if channel_extra is not None:
            if not isinstance(channel_extra, Mapping):
                raise TypeError("channel_extra must map channel selectors to update mappings")
            resolved: set[int] = set()
            for selector, updates in channel_extra.items():
                normalized_updates = _validate_channel_extra(updates)
                index = self._resolve_one_channel(selector)
                if index in resolved:
                    raise ValueError(f"Duplicate channel selector resolves to index {index}")
                resolved.add(index)
                extra = {} if replace else dict(descriptors[index]["extra"])
                extra.update(normalized_updates)
                descriptors[index]["extra"] = extra
        return self._create_new_instance(
            self._data,
            label=normalized_label,
            metadata=new_metadata,
            channel_metadata=descriptors,
            channel_ids=self._channel_ids,
            source_time_offset=self.source_time_offset,
            lineage=self.lineage,
        )

    @recipe_operation(
        "wandas.frame.with_source_time_offset",
        capture=_capture_source_time_offset,
        handler=_apply_source_time_offset_recipe,
        validate_params=_validate_source_time_offset_recipe_params,
    )
    def with_source_time_offset(self: S, value: float | Sequence[float] | NDArrayReal) -> S:
        """Return a Recipe-capable copy preserving scalar or vector call intent."""
        offsets = self._normalize_source_time_offset(value, self.n_channels)
        return self._create_new_instance(
            self._data,
            source_time_offset=offsets,
            lineage=self._required_semantic_lineage(),
        )

    @recipe_operation(
        "wandas.channel.rename_channels",
        capture=_capture_rename_channels,
        handler=_rename_channels_recipe,
        validate_params=_validate_rename_recipe_params,
    )
    def rename_channels(self: S, mapping: Mapping[int | str, str]) -> S:
        """Return a copy with channel labels renamed by index or current label."""
        mapping = _normalize_rename_mapping(mapping)
        labels = self.labels
        new_labels = labels.copy()
        resolved: dict[int, str] = {}
        for key, new_label in mapping.items():
            if type(key) is int:
                if not 0 <= key < self.n_channels:
                    raise KeyError(f"Channel index out of range: {key}")
                index = key
            else:
                matches = [i for i, label in enumerate(labels) if label == key]
                if not matches:
                    raise KeyError(f"Channel label not found: {key!r}")
                if len(matches) > 1:
                    raise ValueError(f"Channel label is ambiguous: {key!r}")
                index = matches[0]
            if index in resolved:
                raise ValueError(f"Duplicate channel rename mapping for index {index}")
            resolved[index] = new_label
            new_labels[index] = new_label
        if len(set(new_labels)) != len(new_labels):
            raise ValueError(f"Duplicate channel label after rename: {new_labels}")
        descriptors = self._borrowed_channel_metadata_descriptors()
        for descriptor, new_label in zip(descriptors, new_labels, strict=True):
            descriptor["label"] = new_label
        return self._create_new_instance(
            self._data,
            channel_metadata=descriptors,
            channel_ids=self._channel_ids,
            lineage=self._required_semantic_lineage(),
        )

    def _channel_indices_from_query(self, query: QueryType, validate_keys: bool) -> list[int]:
        """Resolve a public metadata query to ordered channel indices."""
        if isinstance(query, str):
            return [index for index, channel in enumerate(self.channels) if channel.label == query]
        if isinstance(query, Pattern):
            return [index for index, channel in enumerate(self.channels) if query.search(channel.label)]
        if callable(query):
            predicate = cast(Callable[[ChannelMetadata], bool], query)
            return [index for index, channel in enumerate(self.channels) if predicate(channel)]
        if not isinstance(query, Mapping):
            raise TypeError(f"Unsupported query type: {type(query).__name__}")
        if validate_keys:
            known_keys = set(ChannelMetadata._MODEL_FIELDS)
            for channel in self.channels:
                known_keys.update(channel.extra)
            unknown_keys = [key for key in query if key not in known_keys]
            if unknown_keys:
                raise KeyError("Unknown channel metadata key(s): " + ", ".join(map(str, unknown_keys)))
        return [index for index, channel in enumerate(self.channels) if channel.matches_query(dict(query))]

    def _channel_indices(self, selector: Any) -> list[int]:
        """Normalize and validate one channel selector as an index list."""
        if isinstance(selector, numbers.Integral) and not isinstance(selector, bool | np.bool_):
            index = int(selector)
            if index < -self.n_channels or index >= self.n_channels:
                raise IndexError(f"Channel index out of range: {index}")
            return [index]
        if isinstance(selector, str):
            return [self.label2index(selector)]
        if isinstance(selector, slice):
            return list(range(self.n_channels))[selector]
        if isinstance(selector, np.ndarray):
            if selector.ndim != 1:
                raise ValueError(f"Channel selector must be 1-D, got shape {selector.shape}")
            if np.issubdtype(selector.dtype, np.bool_):
                if len(selector) != self.n_channels:
                    raise ValueError(
                        f"Boolean mask length {len(selector)} does not match number of channels {self.n_channels}"
                    )
                return [int(index) for index in np.flatnonzero(selector)]
            if np.issubdtype(selector.dtype, np.integer):
                return self._channel_indices(selector.tolist())
            raise TypeError(f"NumPy selector must have integer or boolean dtype, got {selector.dtype}")
        if isinstance(selector, tuple):
            selector = list(selector)
        if isinstance(selector, list):
            if not selector:
                raise ValueError("Cannot index with an empty list")
            if all(isinstance(item, str) for item in selector):
                return [self.label2index(item) for item in selector]
            if all(isinstance(item, numbers.Integral) and not isinstance(item, bool | np.bool_) for item in selector):
                indices = [int(item) for item in selector]
                for index in indices:
                    if index < -self.n_channels or index >= self.n_channels:
                        raise IndexError(f"Channel index out of range: {index}")
                return indices
            raise TypeError(f"Channel list contains mixed or unsupported values: {selector!r}")
        raise TypeError(f"Invalid channel selector type: {type(selector).__name__}")

    def _select_channels(self: S, indices: list[int], lineage: LineageNode) -> S:
        """Create a channel subset that preserves metadata, offsets, and lineage."""
        return self._create_new_instance(
            data=self._data[indices],
            channel_metadata=self._borrowed_channel_metadata_descriptors(indices),
            channel_ids=self._channel_ids_for_selection(indices),
            source_time_offset=self.source_time_offset[indices],
            lineage=lineage,
        )

    @recipe_operation(
        "wandas.frame.get_channel",
        capture=_capture_get_channel,
        handler=_apply_get_channel_recipe,
    )
    def get_channel(
        self: S,
        channel_idx: int | list[int] | tuple[int, ...] | npt.NDArray[np.int_] | npt.NDArray[np.bool_] | None = None,
        query: QueryType | None = None,
        validate_query_keys: bool = True,
    ) -> S:
        """
        Get channel(s) by index.

        Parameters
        ----------
        channel_idx : int or sequence of int
            Single channel index or sequence of channel indices.
            Supports negative indices (e.g., -1 for the last channel).
        query : str, re.Pattern, callable, or dict, optional
            If a query is provided, use it to derive indices and ignore the positional channel_idx argument.
            Query to select channels based on metadata. Supported types:
            - str: exact label match
            - re.Pattern: regex search against label
            - callable(ChannelMetadata) -> bool: predicate on channel metadata
            - dict: attribute equality on ChannelMetadata (values may be re.Pattern)
        validate_query_keys : bool, default True
            If True (default), dict queries that contain unknown keys (neither
            model fields nor any channel `extra` keys) will raise `KeyError`.
            Set to False to disable this strict validation and allow callers
            to attempt matches without pre-validation.
        Returns
        -------
        S
            New instance containing the selected channel(s).

        Examples
        --------
        >>> frame.get_channel(0)  # Single channel
        >>> frame.get_channel([0, 2, 3])  # Multiple channels
        >>> frame.get_channel((-1, -2))  # Last two channels
        >>> frame.get_channel(np.array([1, 2]))  # NumPy array of indices
        """

        if query is not None:
            indices = self._channel_indices_from_query(query, validate_query_keys)
            if not indices:
                raise KeyError(f"No channels match query: {query!r}")
        else:
            if channel_idx is None:
                raise TypeError("Either 'channel_idx' or 'query' must be provided.")
            indices = self._channel_indices(channel_idx)
        return self._select_channels(indices, self._required_semantic_lineage())

    def __len__(self) -> int:
        """
        Returns the number of channels.
        """
        return len(self._channel_metadata)

    def __iter__(self: S) -> Iterator[S]:
        """Yield immutable single-channel Frame selections in channel order."""
        for idx in range(len(self)):
            yield self[idx]

    @recipe_operation(
        "wandas.frame.index",
        capture=_capture_index,
        handler=_apply_index_recipe,
    )
    def __getitem__(
        self: S,
        key: int
        | str
        | slice
        | list[int]
        | list[str]
        | tuple[
            int | str | slice | list[int] | list[str] | npt.NDArray[np.int_] | npt.NDArray[np.bool_],
            ...,
        ]
        | npt.NDArray[np.int_]
        | npt.NDArray[np.bool_],
    ) -> S:
        """
        Get channel(s) by index, label, or advanced indexing.

        This method supports multiple indexing patterns similar to NumPy and pandas:

        - Single channel by index: `frame[0]`
        - Single channel by label: `frame["ch0"]`
        - Slice of channels: `frame[0:3]`
        - Multiple channels by indices: `frame[[0, 2, 5]]`
        - Multiple channels by labels: `frame[["ch0", "ch2"]]`
        - NumPy integer array: `frame[np.array([0, 2])]`
        - Boolean mask: `frame[mask]` where mask is a boolean array
        - Multidimensional indexing: `frame[0, 100:200]` (channel + axis slice)

        Parameters
        ----------
        key : int, str, slice, list, tuple, or ndarray
            - int: Single channel index (supports negative indexing)
            - str: Single channel label
            - slice: Range of channels
            - list[int]: Multiple channel indices
            - list[str]: Multiple channel labels
            - tuple: A channel selector followed by slices for semantic axes such
              as frequency or time
            - ndarray[int]: NumPy array of channel indices
            - ndarray[bool]: Boolean mask for channel selection

        Returns
        -------
        S
            New instance containing the selected channel(s).

        Raises
        ------
        ValueError
            If the key length is invalid for the shape, a non-channel selector
            is not a slice, a time slice is stepped or reversed, or a boolean mask
            length doesn't match the channels.
        IndexError
            If the channel index is out of range.
        TypeError
            If the key type is invalid or list contains mixed types.
        KeyError
            If a channel label is not found.

        Examples
        --------
        >>> # Single channel selection
        >>> frame[0]  # First channel
        >>> frame["acc_x"]  # By label
        >>> frame[-1]  # Last channel
        >>>
        >>> # Multiple channel selection
        >>> frame[[0, 2, 5]]  # Multiple indices
        >>> frame[["acc_x", "acc_z"]]  # Multiple labels
        >>> frame[0:3]  # Slice
        >>>
        >>> # NumPy array indexing
        >>> frame[np.array([0, 2, 4])]  # Integer array
        >>> mask = np.array([True, False, True])
        >>> frame[mask]  # Boolean mask
        >>>
        >>> # Time slicing (multidimensional)
        >>> frame[0, 100:200]  # Channel 0, samples 100-200
        >>> frame[[0, 1], 100:200]  # Channels 0-1, continuous sample slice
        """
        if isinstance(key, tuple) and len(key) == 1:
            key = key[0]
        lineage = self._required_semantic_lineage()
        if isinstance(key, tuple):
            return self._handle_multidim_indexing(cast(tuple[Any, ...], key))
        return self._select_channels(self._channel_indices(key), lineage)

    def _handle_multidim_indexing(self: S, key: tuple[Any, ...]) -> S:
        """Handle rank-preserving channel and non-channel axis selection.

        Parameters
        ----------
        key : tuple
            The first element selects channels. Each remaining element must be a
            slice along the corresponding semantic axis, such as frequency or time.

        Returns
        -------
        S
            New instance with the selected channels and axis ranges.

        Raises
        ------
        ValueError
            If the key length exceeds the data dimensions, a non-channel selector
            is not a slice, or a time-axis slice is stepped or reversed.
        """
        if len(key) > self._data.ndim:
            raise ValueError(f"Invalid key length: {len(key)} for shape {self.shape}")

        indices = self._channel_indices(key[0])
        axis_selectors = key[1:]
        selected_data = self._data[indices]
        source_time_offset = self.source_time_offset[indices]
        if axis_selectors:
            if not all(isinstance(selector, slice) for selector in axis_selectors):
                raise ValueError(
                    "Only slice selectors on non-channel axes are supported; "
                    "use a one-element slice for point selection"
                )
            time_slice_context = self._source_time_slice_context(axis_selectors)
            if time_slice_context is not None:
                time_axis_key, time_axis_size, time_step = time_slice_context
                if time_axis_key.step not in (None, 1):
                    raise ValueError("Only continuous forward slicing on the time axis is supported")
                start, _, _ = time_axis_key.indices(time_axis_size)
                source_time_offset = source_time_offset + start * time_step
            selected_data = selected_data[(slice(None),) + axis_selectors]  # noqa: RUF005
        return self._create_new_instance(
            data=selected_data,
            channel_metadata=self._borrowed_channel_metadata_descriptors(indices),
            channel_ids=self._channel_ids_for_selection(indices),
            source_time_offset=source_time_offset,
            lineage=self._required_semantic_lineage(),
        )

    def _channel_selector_for_lineage(self, key: Any) -> dict[str, Any] | None:
        """Encode the channel part of a multidimensional index when portable."""
        if isinstance(key, numbers.Integral) and not isinstance(key, bool | np.bool_):
            return {"indexing": "integer", "index": int(key)}
        if isinstance(key, str):
            return {"indexing": "label", "label": key}
        if isinstance(key, slice):
            bounds = self._slice_for_lineage(key)
            return None if bounds is None else {"indexing": "channel_slice", **bounds}
        if isinstance(key, list) and key and all(isinstance(item, str) for item in key):
            return {"indexing": "label_list", "labels": tuple(key)}
        if (
            isinstance(key, list)
            and key
            and all(isinstance(item, numbers.Integral) and not isinstance(item, bool | np.bool_) for item in key)
        ):
            return {"indexing": "integer_list", "indices": tuple(int(item) for item in key)}
        if isinstance(key, np.ndarray) and key.ndim == 1 and np.issubdtype(key.dtype, np.bool_):
            return {"indexing": "boolean_mask", "mask": tuple(bool(item) for item in key.tolist())}
        if isinstance(key, np.ndarray) and key.ndim == 1 and np.issubdtype(key.dtype, np.integer):
            return {"indexing": "integer_array", "indices": tuple(int(item) for item in key.tolist())}
        return None

    def _source_time_slice_context(self, keys: tuple[Any, ...]) -> tuple[Any, int, float] | None:
        """Return the sliced time-axis key, axis size, and seconds per index."""
        dims = self._xr.dims
        if "time" not in dims:
            return None
        time_dim_index = dims.index("time")
        key_index = time_dim_index - 1
        if key_index < 0 or key_index >= len(keys):
            return None
        hop_length = getattr(self, "hop_length", 1)
        return keys[key_index], self._data.shape[time_dim_index], float(hop_length) / self.sampling_rate

    def label2index(self, label: str) -> int:
        """
        Get the index from a channel label.

        Parameters
        ----------
        label : str
            Channel label.

        Returns
        -------
        int
            Corresponding index.

        Raises
        ------
        KeyError
            If the channel label is not found.
        """
        for idx, ch in enumerate(self.channels):
            if ch.label == label:
                return idx
        raise KeyError(f"Channel label '{label}' not found.")

    @property
    def shape(self) -> tuple[int, ...]:
        """Return data shape with the singleton channel dimension suppressed."""
        _shape: tuple[int, ...] = self._data.shape
        if _shape[0] == 1:
            return _shape[1:]
        return _shape

    @property
    def data(self) -> T:
        """Return the frame's calibrated values as a NumPy array.

        Channel calibration factors are applied automatically. A single-channel
        frame returns an array without the singleton channel axis; multichannel
        frames preserve the channel axis.
        """
        data = self._compute()
        if self.n_channels == 1:
            return cast(T, data.squeeze(axis=0))
        return data

    @property
    def labels(self) -> list[str]:
        """Get a list of all channel labels."""
        return [ch.label for ch in self.channels]

    def _compute(self) -> T:
        """Return calibrated values while preserving every frame dimension.

        This private materialization boundary is for internal code that requires
        the channel-first representation, including its singleton channel axis.

        Returns
        -------
        NDArrayReal
            The computed data.

        Raises
        ------
        ValueError
            If the computed result is not a NumPy array.
        """
        logger.debug("COMPUTING DASK ARRAY - This will trigger file reading and all processing")
        result = self._effective_data.compute()

        if not isinstance(result, np.ndarray):
            raise ValueError(f"Computed result is not a np.ndarray: {type(result)}")

        logger.debug(f"Computation complete, result shape: {result.shape}")
        return cast(T, result)

    @abstractmethod
    def plot(self, plot_type: str = "default", ax: "Axes | None" = None, **kwargs: Any) -> "Axes | Iterator[Axes]":
        """Plot the data"""

    def save(
        self,
        path: str | Path,
        *,
        compress: str | None = "gzip",
        overwrite: bool = False,
    ) -> None:
        """Save this exact built-in Frame type as a WDF 0.4 artifact.

        WDF stores the raw tensor together with the constructor state, semantic
        dimensions, channel calibration, metadata, and display history needed to
        reconstruct the same Frame type. Runtime lineage and the Dask task graph are
        intentionally outside the persistence boundary.

        Args:
            path: Destination path. The ``.wdf`` suffix is appended when absent.
            compress: HDF5 dataset compression filter, or ``None`` for no
                compression.
            overwrite: Replace an existing artifact when true.

        Raises:
            FileExistsError: If the destination exists and ``overwrite`` is false.
            TypeError: If this is not an exact supported built-in Frame type.
            ValueError: If Frame state cannot be represented by the current schema.
        """
        from wandas.io.wdf_io import save as wdf_save

        wdf_save(
            self,
            path,
            compress=compress,
            overwrite=overwrite,
        )

    def _get_additional_init_kwargs(self) -> dict[str, Any]:
        """Return additional keyword arguments for ``_create_new_instance``.

        Subclasses that require extra constructor parameters (e.g. ``n_fft``,
        ``hop_length``) should override this method.  The default returns an
        empty dict, which is correct for frames with no extra init args
        (e.g. ``ChannelFrame``).
        """
        return {}

    def _create_new_instance(self: S, data: DaArray, **kwargs: Any) -> S:
        """Reconstruct this Frame type around new lazy data.

        Keyword arguments override copied Frame state. Subclass constructor state is
        supplied by :meth:`_get_additional_init_kwargs`, and compatible represented
        xarray dimension coordinates are restored after construction.
        """

        sampling_rate = kwargs.pop("sampling_rate", self.sampling_rate)

        label = _normalize_frame_label(kwargs.pop("label", self.label))

        metadata = kwargs.pop("metadata") if "metadata" in kwargs else self.metadata
        _validate_frame_metadata(metadata)

        lineage = kwargs.pop("lineage", self.lineage)

        channel_metadata = (
            kwargs.pop("channel_metadata")
            if "channel_metadata" in kwargs
            else self._borrowed_channel_metadata_descriptors()
        )
        if not isinstance(channel_metadata, list):
            raise TypeError("Channel metadata must be a list")

        channel_ids = kwargs.pop("channel_ids", None)
        if channel_ids is None:
            channel_ids = (
                self._channel_ids
                if len(channel_metadata) == self.n_channels
                else self._default_channel_ids(len(channel_metadata))
            )
        if not isinstance(channel_ids, list):
            raise TypeError("Channel ids must be a list")

        source_time_offset = kwargs.pop("source_time_offset", self.source_time_offset)

        # Get additional initialization arguments from derived classes
        additional_kwargs = self._get_additional_init_kwargs()
        kwargs.update(additional_kwargs)

        init_kwargs: dict[str, Any] = {
            "data": data,
            "sampling_rate": sampling_rate,
            "label": label,
            "metadata": metadata,
            "channel_metadata": channel_metadata,
            "channel_ids": channel_ids,
            "source_time_offset": source_time_offset,
            "previous": self,
            "lineage": lineage,
            **kwargs,
        }
        result = type(self)(**init_kwargs)

        # Constructors create canonical xarray dimensions and coordinates. Preserve
        # a represented axis (for example, a sliced quefrency axis) only when it is a
        # one-dimensional coordinate attached to the same dimension and the new
        # tensor kept that dimension's size. Channel coordinates are rebuilt from
        # channel metadata above and must not be overwritten here.
        for dim in self._xr.dims:
            if (
                dim != self._CHANNEL_DIM
                and dim in self._xr.coords
                and dim in result._xr.dims
                and int(result._xr.sizes[dim]) == int(self._xr.sizes[dim])
            ):
                coordinate = self._xr.coords[dim]
                if coordinate.dims == (dim,):
                    result._xr = result._xr.assign_coords({dim: (dim, coordinate.values.copy())})
        return result

    def _metadata_after_analysis(
        self,
        channel_metadata: Sequence[ChannelMetadata] | None = None,
    ) -> list[dict[str, Any]]:
        """Describe channel metadata after consuming each calibration factor."""
        source = self.channels if channel_metadata is None else channel_metadata
        result: list[dict[str, Any]] = []
        for channel in source:
            result.append(
                {
                    "label": channel.label,
                    "calibration": ChannelCalibration(
                        factor=1.0,
                        unit=channel.unit,
                        ref=channel.ref,
                    ),
                    "extra": channel.extra,
                }
            )
        return result

    def __array__(self, dtype: npt.DTypeLike = None, copy: bool | None = None) -> NDArrayReal:
        """Implicit conversion to NumPy array"""
        if copy is False:
            raise ValueError("A Dask-backed Frame cannot provide a zero-copy NumPy array.")

        result = self.data
        if dtype is not None:
            result = result.astype(dtype, copy=copy is True)
        elif copy is True:
            result = result.copy()
        return cast(NDArrayReal, result)

    def __array_ufunc__(self, ufunc: np.ufunc, method: str, *inputs: Any, **kwargs: Any) -> Any:
        """Handle NumPy scalar-left operators without forcing eager arrays."""
        if method == "__call__" and len(inputs) == 2 and inputs[1] is self and isinstance(inputs[0], np.generic):
            reverse_method_name = self._array_ufunc_reverse_methods.get(ufunc.__name__)
            if reverse_method_name is not None:
                result = getattr(self, reverse_method_name)(inputs[0])
                return result
        array_inputs = tuple(np.asarray(input_value) if input_value is self else input_value for input_value in inputs)
        return getattr(ufunc, method)(*array_inputs, **kwargs)

    def visualize_graph(self, filename: str | None = None) -> VisualizeReturnType:
        """
        Visualize the computation graph and save it to a file.

        This method creates a visual representation of the Dask computation graph.
        In interactive Python environments, it returns an IPython.display.Image object
        that can be displayed inline. In other environments, it saves the graph to
        a file and returns None.

        Parameters
        ----------
        filename : str, optional
            Output filename for the graph image. If None, a unique filename
            is generated using UUID. The file is saved in the current working
            directory.

        Returns
        -------
        IPython.display.Image or None
            In interactive Python environments: Returns an IPython.display.Image object
            that can be displayed inline.
            In other environments: Returns None after saving the graph to file.

        Notes
        -----
        This method requires graphviz to be installed on your system:
        - Ubuntu/Debian: `sudo apt-get install graphviz`
        - macOS: `brew install graphviz`
        - Windows: Download from https://graphviz.org/download/

        The graph displays operation names (e.g., 'normalize', 'lowpass_filter')
        making it easier to understand the processing pipeline.

        Examples
        --------
        >>> import wandas as wd
        >>> signal = wd.read("audio.wav")
        >>> processed = signal.normalize().low_pass_filter(cutoff=1000)
        >>> # In interactive environments: displays graph inline
        >>> processed.visualize_graph()
        >>> # Save to specific file
        >>> processed.visualize_graph("my_graph.png")

        See Also
        --------
        debug_info : Print detailed debug information about the frame
        """
        try:
            filename = filename or f"graph_{uuid.uuid4().hex[:8]}.png"
            return self._effective_data.visualize(filename=filename)
        except Exception as e:
            logger.warning(f"Failed to visualize the graph: {e}")
            return None

    def _binary_op(
        self: S,
        other: S | int | float | complex | NDArrayReal | DaArray,
        op: Callable[[DaArray, Any], DaArray],
        symbol: str,
    ) -> S:
        """Apply a forward lazy binary operation through the shared implementation."""
        return self._binary_operand_op(other, op, symbol, reverse=False)

    def _binary_operand_op(
        self: S,
        other: S | int | float | complex | NDArrayReal | DaArray,
        op: Callable[[Any, Any], Any],
        symbol: str,
        *,
        reverse: bool = False,
    ) -> S:
        """Default implementation of binary operations using dask's lazy evaluation.

        Handles both frame-frame and frame-scalar/array operations with
        metadata propagation and runtime lineage tracking. Frame-frame operations are
        index-wise: they combine current array positions without using the right
        operand's coordinates for alignment or relabeling. They do not compare
        ``source_time_offset`` values and do not perform source-time alignment,
        trimming, or padding. Results preserve the left operand's source-time offset
        and compatible dimension coordinates through ``_create_new_instance``. Uses
        ``_create_new_instance`` so that subclass-specific constructor parameters are
        automatically forwarded.

        Subclasses may override this entirely (e.g. ``RoughnessFrame``).
        """
        logger.debug(f"Setting up {symbol} operation (lazy)")

        metadata = self.metadata
        if isinstance(other, BaseFrame):
            if self.sampling_rate != other.sampling_rate:
                raise ValueError(
                    f"Sampling rate mismatch\n"
                    f"  Left operand: {self.sampling_rate} Hz\n"
                    f"  Right operand: {other.sampling_rate} Hz\n"
                    f"Resample one frame to match the other before performing "
                    f"{symbol} operation."
                )
            if self.n_channels != other.n_channels:
                raise ValueError(
                    f"Channel count mismatch\n"
                    f"  Left operand: {self.n_channels} channels\n"
                    f"  Right operand: {other.n_channels} channels\n"
                    f"Binary frame operations require matching channel counts to keep "
                    f"channel metadata aligned.\n"
                    f"Select, duplicate, or remove channels so both operands match "
                    f"before performing {symbol} operation."
                )
            if self._data.shape != other._data.shape or self._xr.dims != other._xr.dims:
                raise ValueError(
                    f"Frame shape mismatch\n"
                    f"  Left operand: {self._data.shape} with axes {self._xr.dims}\n"
                    f"  Right operand: {other._data.shape} with axes {other._xr.dims}\n"
                    f"Binary frame operations require identical semantic shapes."
                )
            result_data = op(self._effective_data, other._effective_data)
            other_str = other.label
            other_labels = other.labels
        else:
            result_data = op(other, self._effective_data) if reverse else op(self._effective_data, other)
            other_str = self._format_operand_str(other)
            other_labels = [other_str] * self.n_channels

        # Build borrowed constructor descriptors and consume calibration once.
        new_channel_metadata = self._metadata_after_analysis()
        for descriptor, self_ch, other_label in zip(
            new_channel_metadata,
            self.channels,
            other_labels,
            strict=True,
        ):
            if reverse and not isinstance(other, BaseFrame):
                descriptor["label"] = f"({other_label} {symbol} {self_ch.label})"
            else:
                descriptor["label"] = f"({self_ch.label} {symbol} {other_label})"

        label = (
            f"({other_str} {symbol} {self.label})"
            if reverse and not isinstance(other, BaseFrame)
            else f"({self.label} {symbol} {other_str})"
        )
        return self._create_new_instance(
            data=result_data,
            label=label,
            metadata=metadata,
            lineage=self._required_semantic_lineage(),
            channel_metadata=new_channel_metadata,
        )

    @staticmethod
    def _is_supported_reverse_scalar(value: object) -> bool:
        """Return whether base reverse arithmetic accepts this scalar."""
        return isinstance(value, numbers.Real) and not isinstance(value, bool)

    def _supports_base_reverse_scalar_op(self) -> bool:
        """Return whether the concrete class retains BaseFrame binary semantics."""
        return type(self)._binary_op is BaseFrame._binary_op

    @staticmethod
    def _format_operand_str(other: object) -> str:
        """Return a short display string for a binary operand."""
        if isinstance(other, int | float):
            return str(other)
        if isinstance(other, np.bool_):
            return str(bool(other))
        if isinstance(other, complex):
            return f"complex({other.real}, {other.imag})"
        if isinstance(other, np.ndarray):
            return f"ndarray{other.shape}"
        if hasattr(other, "shape"):
            return f"dask.array{other.shape}"
        return str(type(other).__name__)

    @recipe_operation(
        "wandas.operator.add",
        binding_patterns=_FORWARD_BINARY_PATTERNS,
        capture=_capture_binary,
        handler=_binary_recipe_handler("__add__"),
    )
    def __add__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
        """Addition operator"""
        return self._binary_op(other, lambda x, y: x + y, "+")

    @recipe_operation(
        "wandas.operator.subtract",
        binding_patterns=_FORWARD_BINARY_PATTERNS,
        capture=_capture_binary,
        handler=_binary_recipe_handler("__sub__"),
    )
    def __sub__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
        """Subtraction operator"""
        return self._binary_op(other, lambda x, y: x - y, "-")

    @recipe_operation(
        "wandas.operator.multiply",
        binding_patterns=_FORWARD_BINARY_PATTERNS,
        capture=_capture_binary,
        handler=_binary_recipe_handler("__mul__"),
    )
    def __mul__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
        """Multiplication operator"""
        return self._binary_op(other, lambda x, y: x * y, "*")

    @recipe_operation(
        "wandas.operator.divide",
        binding_patterns=_FORWARD_BINARY_PATTERNS,
        capture=_capture_binary,
        handler=_binary_recipe_handler("__truediv__"),
    )
    def __truediv__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
        """Division operator"""
        return self._binary_op(other, lambda x, y: x / y, "/")

    @recipe_operation(
        "wandas.operator.power",
        binding_patterns=_FORWARD_BINARY_PATTERNS,
        capture=_capture_binary,
        handler=_binary_recipe_handler("__pow__"),
    )
    def __pow__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
        """Power operator"""
        return self._binary_op(other, lambda x, y: x**y, "**")

    @recipe_operation(
        "wandas.operator.reverse_add",
        binding_patterns=_REVERSE_BINARY_PATTERNS,
        capture=_capture_reverse_binary,
        handler=_binary_recipe_handler("__radd__"),
    )
    def __radd__(self: S, other: int | float) -> S:
        """Reverse addition operator."""
        if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
            return NotImplemented
        return self._binary_operand_op(other, lambda x, y: x + y, "+", reverse=True)

    @recipe_operation(
        "wandas.operator.reverse_subtract",
        binding_patterns=_REVERSE_BINARY_PATTERNS,
        capture=_capture_reverse_binary,
        handler=_binary_recipe_handler("__rsub__"),
    )
    def __rsub__(self: S, other: int | float) -> S:
        """Reverse subtraction operator."""
        if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
            return NotImplemented
        return self._binary_operand_op(other, lambda x, y: x - y, "-", reverse=True)

    @recipe_operation(
        "wandas.operator.reverse_multiply",
        binding_patterns=_REVERSE_BINARY_PATTERNS,
        capture=_capture_reverse_binary,
        handler=_binary_recipe_handler("__rmul__"),
    )
    def __rmul__(self: S, other: int | float) -> S:
        """Reverse multiplication operator."""
        if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
            return NotImplemented
        return self._binary_operand_op(other, lambda x, y: x * y, "*", reverse=True)

    @recipe_operation(
        "wandas.operator.reverse_divide",
        binding_patterns=_REVERSE_BINARY_PATTERNS,
        capture=_capture_reverse_binary,
        handler=_binary_recipe_handler("__rtruediv__"),
    )
    def __rtruediv__(self: S, other: int | float) -> S:
        """Reverse division operator."""
        if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
            return NotImplemented
        return self._binary_operand_op(other, lambda x, y: x / y, "/", reverse=True)

    @recipe_operation(
        "wandas.operator.reverse_power",
        binding_patterns=_REVERSE_BINARY_PATTERNS,
        capture=_capture_reverse_binary,
        handler=_binary_recipe_handler("__rpow__"),
    )
    def __rpow__(self: S, other: int | float) -> S:
        """Reverse power operator."""
        if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
            return NotImplemented
        return self._binary_operand_op(other, lambda x, y: x**y, "**", reverse=True)

    def _apply_named_operation(self: S, operation_name: str, **params: Any) -> S:
        """Execute a numerical operation inside a decorated public boundary."""
        self._required_semantic_lineage()
        return self._apply_operation_impl(operation_name, **params)

    def _updated_metadata(
        self,
        operation_name: str,
        params: Mapping[str, Any],
    ) -> dict[str, Any]:
        """Return frame metadata for a derived frame.

        Operation parameters are owned by runtime lineage. Frame metadata only
        carries user/domain metadata; the receiving Frame constructor takes its
        one defensive ownership copy.
        """
        return self.metadata

    def _apply_operation_impl(self: S, operation_name: str, **params: Any) -> S:
        """Default implementation of operation application.

        Creates the named operation, applies it to the data, and returns
        a new frame with updated metadata and runtime lineage.
        Derived classes may override this to add extra behaviour
        (e.g. channel relabelling).
        """
        logger.debug(f"Applying operation={operation_name} with params={params} (lazy)")
        from wandas.processing import create_operation

        operation = create_operation(operation_name, self.sampling_rate, **params)
        ensure_dependencies = getattr(operation, "ensure_dependencies", None)
        if ensure_dependencies is not None:
            ensure_dependencies()
        processed_data = operation.process(self._effective_data)

        new_metadata = self._updated_metadata(operation_name, params)

        creation_params: dict[str, Any] = {
            "data": processed_data,
            "metadata": new_metadata,
            "lineage": self._required_semantic_lineage(),
            "channel_metadata": self._metadata_after_analysis(),
        }

        return self._create_new_instance(**creation_params)

    @overload
    def _apply_operation_instance(
        self: S,
        operation: Any,
        operation_name: str | None = None,
        output_frame_class: None = None,
        output_frame_kwargs: dict[str, Any] | None = None,
    ) -> S: ...

    @overload
    def _apply_operation_instance(
        self: S,
        operation: Any,
        operation_name: str | None = None,
        output_frame_class: type[S_Out] = ...,
        output_frame_kwargs: dict[str, Any] | None = None,
    ) -> S_Out: ...

    def _apply_operation_instance(
        self: S,
        operation: Any,
        operation_name: str | None = None,
        output_frame_class: type[S_Out] | None = None,
        output_frame_kwargs: dict[str, Any] | None = None,
    ) -> S | S_Out:
        """Apply an already-instantiated operation to the frame.

        This method processes data through the operation, updates metadata,
        runtime lineage, and channel labels atomically.  It is the
        entry-point used by ``ChannelProcessingMixin`` and by
        ``ChannelFrame._apply_operation_impl``.

        Parameters
        ----------
        operation : AudioOperation
            Instantiated operation to apply.
        operation_name : str, optional
            Numerical operation name used for metadata and display handling. The
            enclosing ``@recipe_operation`` declaration owns the history operation ID.
        output_frame_class : type, optional
            If provided, the result is wrapped in this frame class instead
            of the same type as ``self``.  Enables domain transitions
            (e.g. ChannelFrame -> SpectralFrame) from ``apply()``.
        output_frame_kwargs : dict, optional
            Extra constructor keyword arguments required by *output_frame_class*
            (e.g. ``{"n_fft": 1024, "window": "hann"}``).
        """
        if operation_name is None:
            operation_name = getattr(operation, "name", "unknown_operation")
        expected_input_count = getattr(operation, "_expected_input_count", 1)
        if isinstance(expected_input_count, int) and expected_input_count != 1:
            raise ValueError(
                "Operation requires multiple runtime inputs\n"
                f"  Operation: {operation_name}\n"
                f"  Expected inputs: {expected_input_count}\n"
                "  Got: this helper provides one frame input\n"
                "Use an operation-specific method that can pass all runtime inputs."
            )

        ensure_dependencies = getattr(operation, "ensure_dependencies", None)
        if ensure_dependencies is not None:
            ensure_dependencies()
        processed_data = operation.process(self._effective_data)

        params = getattr(operation, "params", {})

        new_metadata = self._updated_metadata(operation_name, params)
        lineage = self._required_semantic_lineage()

        metadata_updates = operation.get_metadata_updates()
        if operation_name == "trim":
            start_sample = int(float(params.get("start", 0.0)) * self.sampling_rate)
            metadata_updates["source_time_offset"] = self.source_time_offset + start_sample / self.sampling_rate

        display = operation.get_display_name() or operation_name
        new_channel_metadata = self._metadata_after_analysis()
        for descriptor, channel in zip(new_channel_metadata, self.channels, strict=True):
            descriptor["label"] = f"{display}({channel.label})"

        if output_frame_class is not None:
            if not isinstance(output_frame_class, type) or not issubclass(output_frame_class, BaseFrame):
                raise TypeError(
                    "Invalid output_frame_class\n"
                    f"  Got: {output_frame_class!r}\n"
                    f"  Expected: a BaseFrame subclass\n"
                    f"Pass a compatible Wandas frame class such as "
                    f"SpectralFrame or SpectrogramFrame."
                )
            # Domain transition: build a different frame type
            kw: dict[str, Any] = {
                "data": processed_data,
                "sampling_rate": metadata_updates.pop("sampling_rate", self.sampling_rate),
                "label": self.label,
                "metadata": new_metadata,
                "channel_metadata": new_channel_metadata,
                "channel_ids": self._channel_ids,
                "source_time_offset": metadata_updates.pop("source_time_offset", self.source_time_offset),
                "previous": self,
                "lineage": lineage,
            }
            kw.update(metadata_updates)
            if output_frame_kwargs:
                kw.update(output_frame_kwargs)
            try:
                return output_frame_class(**kw)
            except TypeError as exc:
                provided_kwargs = ", ".join(sorted(kw)) or "none"
                raise TypeError(
                    "Invalid output_frame_class constructor\n"
                    f"  Frame class: {output_frame_class.__name__}\n"
                    f"  Provided keyword arguments: {provided_kwargs}\n"
                    f"Ensure output_frame_class accepts these parameters and "
                    f"use output_frame_kwargs to supply any required "
                    f"domain-specific constructor arguments."
                ) from exc

        creation_params: dict[str, Any] = {
            "data": processed_data,
            "metadata": new_metadata,
            "lineage": lineage,
            "channel_metadata": new_channel_metadata,
            "channel_ids": self._channel_ids,
        }
        creation_params.update(metadata_updates)

        return self._create_new_instance(**creation_params)

    def _relabel_channels(
        self,
        operation_name: str,
        display_name: str | None = None,
    ) -> list[ChannelMetadata]:
        """
        Update channel labels to reflect applied operation.

        This method creates new channel metadata with labels that include
        the operation name, making it easier to track processing history
        and distinguish frames in plots.

        Parameters
        ----------
        operation_name : str
            Name of the operation (e.g., "normalize", "lowpass_filter")
        display_name : str, optional
            Display name for the operation. If None, uses operation_name.
            This allows operations to provide custom, more readable labels.

        Returns
        -------
        list[ChannelMetadata]
            New channel metadata with updated labels.
            Original metadata is deep-copied and only labels are modified.

        Examples
        --------
        >>> # Original label: "ch0"
        >>> # After normalize: "normalize(ch0)"
        >>> # After chained ops: "lowpass_filter(normalize(ch0))"

        Notes
        -----
        Labels are nested for chained operations, allowing full
        traceability of the processing pipeline.
        """
        display = display_name or operation_name
        new_metadata = []
        for ch in self.channels:
            new_ch = ch.to_metadata()
            new_ch.label = f"{display}({ch.label})"
            new_metadata.append(new_ch)
        return new_metadata

    def debug_info(self) -> None:
        """Output detailed debug information"""
        logger.debug(f"=== {self.__class__.__name__} Debug Info ===")
        logger.debug(f"Label: {self.label}")
        logger.debug(f"Shape: {self.shape}")
        logger.debug(f"Sampling rate: {self.sampling_rate} Hz")
        logger.debug(f"Operation history: {len(self.operation_history)} operations")
        try:
            effective_data = self._effective_data
            logger.debug(f"Dask graph layers: {list(effective_data.dask.layers.keys())}")
            logger.debug(f"Dask graph dependencies: {len(effective_data.dask.dependencies)}")
        except Exception as e:
            logger.debug(f"Dask graph details unavailable: {e}")
        self._debug_info_impl()
        logger.debug("=== End Debug Info ===")

    def print_operation_history(self) -> None:
        """
        Print the operation history to standard output in a readable format.

        This method writes a human-friendly representation of the
        `operation_history` list to stdout. Each operation is printed on its
        own line with an index, the operation name (if available), and the
        parameters used.

        Examples
        --------
        >>> cf.print_operation_history()
        1: normalize {}
        2: low_pass_filter {'cutoff': 1000}
        """
        if not self.operation_history:
            print("Operation history: <empty>")
            return

        print(f"Operation history ({len(self.operation_history)}):")
        for i, record in enumerate(self.operation_history, start=1):
            # record is expected to be a dict with at least a 'operation' key
            op_name = record.get("operation") or record.get("name") or "<unknown>"
            # Copy params for display - exclude the 'operation'/'name' keys
            params = {k: v for k, v in record.items() if k not in ("operation", "name")}
            print(f"{i}: {op_name} {params}")

    def to_numpy(self) -> T:
        """Convert the frame data to a NumPy array.

        This method is equivalent to accessing :attr:`data`.

        Returns
        -------
        T
            NumPy array containing the frame data.

        Examples
        --------
        >>> cf = wd.read("audio.wav")
        >>> data = cf.to_numpy()
        >>> print(f"Shape: {data.shape}")  # (n_channels, n_samples)
        """
        return self.data

    def to_tensor(self, framework: str = "torch", device: str | None = None) -> Any:
        """
        Convert the Dask array to a tensor in the specified framework.

        Parameters
        ----------
        framework : str, default="torch"
            The ML framework to use ("torch" or "tensorflow").
        device : str or None, optional
            Device to place the tensor on. For PyTorch, use "cpu", "cuda", "cuda:0",
            etc. For TensorFlow, use "/CPU:0", "/GPU:0", etc. If None, uses the default
            device.

        Returns
        -------
        torch.Tensor or tf.Tensor
            A tensor in the specified framework.

        Raises
        ------
        ImportError
            If the specified framework is not installed.
        ValueError
            If the framework is not supported.
        TypeError
            If self.data is not a Dask array.

        Examples
        --------
        >>> # PyTorch tensor on CPU
        >>> tensor = frame.to_tensor(framework="torch", device="cpu")
        >>> # PyTorch tensor on GPU
        >>> tensor = frame.to_tensor(framework="torch", device="cuda:0")
        >>> # TensorFlow tensor on GPU
        >>> tensor = frame.to_tensor(framework="tensorflow", device="/GPU:0")
        """

        if framework == "torch":
            torch = require_dependency("torch", feature="tensor conversion with framework='torch'")
            numpy_data = self.to_numpy()

            # Convert NumPy array to PyTorch tensor
            tensor = torch.from_numpy(numpy_data)

            # Move to specified device if provided
            if device is not None:
                tensor = tensor.to(device)

            return tensor

        elif framework == "tensorflow":
            tf = require_dependency(
                "tensorflow",
                feature="tensor conversion with framework='tensorflow'",
            )
            numpy_data = self.to_numpy()

            # Convert NumPy array to TensorFlow tensor
            if device is not None:
                with tf.device(device):
                    tensor = tf.convert_to_tensor(numpy_data)
            else:
                tensor = tf.convert_to_tensor(numpy_data)

            return tensor

        else:
            raise ValueError(
                f"Unsupported framework\n"
                f"  Got: '{framework}'\n"
                f"  Expected: 'torch' or 'tensorflow'\n"
                f"Use a supported framework for tensor conversion"
            )

    def to_dataframe(self) -> "pd.DataFrame":
        """Convert the frame data to a pandas DataFrame.

        This method provides a common implementation for converting frame data
        to pandas DataFrame. Subclasses can override this method for custom behavior.

        Returns
        -------
        pd.DataFrame
            DataFrame with appropriate index and columns.

        Examples
        --------
        >>> cf = wd.read("audio.wav")
        >>> df = cf.to_dataframe()
        >>> print(df.head())
        """
        pd = require_pandas("BaseFrame.to_dataframe")

        # Get data as numpy array
        data = self.to_numpy()

        # Get column names from subclass
        columns = self._get_dataframe_columns()

        # Get index from subclass
        index = self._get_dataframe_index()

        # Create DataFrame
        if data.ndim == 1:
            # Single channel case - reshape to 2D
            df = pd.DataFrame(data.reshape(-1, 1), columns=columns, index=index)
        else:
            # Multi-channel case - transpose to (n_samples, n_channels)
            df = pd.DataFrame(data.T, columns=columns, index=index)

        return df

    def _get_dataframe_columns(self) -> list[str]:
        """Get column names for DataFrame.

        Returns channel labels by default. Override in subclasses
        if different column names are needed.

        Returns
        -------
        list[str]
            List of column names.
        """
        return self.labels

    @abstractmethod
    def _get_dataframe_index(self) -> "pd.Index[Any]":
        """Get index for DataFrame.

        This method should be implemented by subclasses to provide
        appropriate index for the DataFrame based on the frame type.

        Returns
        -------
        pd.Index
            Index for the DataFrame.
        """

    def _debug_info_impl(self) -> None:
        """Implement derived class-specific debug information"""

    def _print_operation_history(self) -> None:
        """Print the operation history information.

        This is a helper method for info() implementations to display
        the number of operations applied to the frame in a consistent format.
        """
        if self.operation_history:
            print(f"  Operations Applied: {len(self.operation_history)}")
        else:
            print("  Operations Applied: None")

Attributes

channels property

Property to access channel metadata.

n_channels property

Returns the number of channels.

previous property

Return the immediate prior frame for compatibility/debug inspection.

This strong reference is not the source of truth for processing history. Runtime lineage drives operation_history and Recipe extraction.

sampling_rate property

Return the frame sampling rate from xarray attrs.

label property

Return the frame label from xarray attrs.

metadata property

Return an owned snapshot of frame metadata.

operation_history property

Return the sole public, JSON-safe provenance projection.

lineage property

Return runtime computation lineage for this frame.

source_time_offset property

Return each channel's offset from local time axis to source time.

shape property

Return data shape with the singleton channel dimension suppressed.

data property

Return the frame's calibrated values as a NumPy array.

Channel calibration factors are applied automatically. A single-channel frame returns an array without the singleton channel axis; multichannel frames preserve the channel axis.

labels property

Get a list of all channel labels.

Functions

__init__(data, sampling_rate, label=None, metadata=None, channel_metadata=None, channel_ids=None, previous=None, source_time_offset=0.0, lineage=None, operation_history_prefix=())

Initialize immutable Frame data, metadata, channel state, and lineage.

Source code in wandas/core/base_frame.py
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def __init__(
    self,
    data: DaArray,
    sampling_rate: float,
    label: str | None = None,
    metadata: dict[str, Any] | None = None,
    channel_metadata: Sequence[ChannelMetadata | dict[str, Any]] | None = None,
    channel_ids: list[str] | None = None,
    previous: "BaseFrame[Any] | None" = None,
    source_time_offset: float | Sequence[float] | NDArrayReal = 0.0,
    lineage: LineageNode | None = None,
    operation_history_prefix: Sequence[Mapping[str, Any]] = (),
):
    """Initialize immutable Frame data, metadata, channel state, and lineage."""
    normalized_sampling_rate = _normalize_sampling_rate(sampling_rate)
    self._pending_sampling_rate = normalized_sampling_rate
    normalized_data = self._normalize_data(data)
    frame_label = _normalize_frame_label(label)
    channel_count = self._channel_size_from_xarray_dims(normalized_data)
    if channel_count is None:
        channel_count = self._channel_count_from_data(normalized_data)

    normalized_channel_metadata = self._normalize_channel_metadata_for_count(channel_metadata, channel_count)
    self._pending_channel_metadata = normalized_channel_metadata
    self._pending_channel_ids = (
        self._validate_channel_ids(channel_ids, channel_count)
        if channel_ids is not None
        else self._default_channel_ids(channel_count)
    )

    self._xr = self._build_xarray(normalized_data, name=frame_label)
    self._write_label(label)
    self._write_normalized_sampling_rate(normalized_sampling_rate)
    self._write_metadata(metadata)
    if lineage is not None and operation_history_prefix:
        raise ValueError("operation_history_prefix is valid only for a new source Frame")
    self._lineage = lineage if lineage is not None else source_lineage(operation_history_prefix)
    self._write_normalized_channel_metadata(normalized_channel_metadata, self._pending_channel_ids)
    self._write_source_time_offset(source_time_offset)
    del self._pending_channel_metadata
    del self._pending_channel_ids
    del self._pending_sampling_rate
    self._previous = previous

    try:
        # Display information for newer dask versions
        effective_data = self._effective_data
        logger.debug(f"Dask graph layers: {list(effective_data.dask.layers.keys())}")
        logger.debug(f"Dask graph dependencies: {len(effective_data.dask.dependencies)}")
    except Exception as e:
        logger.debug(f"Dask graph visualization details unavailable: {e}")

with_label(label)

Return an annotation-only copy with a replacement Frame label.

Source code in wandas/core/base_frame.py
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def with_label(self: S, label: str | None) -> S:
    """Return an annotation-only copy with a replacement Frame label."""
    return self._with_annotations(label=label, label_is_set=True)

with_metadata(updates, *, replace=False)

Return an annotation-only copy with merged or replaced metadata.

Source code in wandas/core/base_frame.py
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def with_metadata(self: S, updates: Mapping[str, Any], *, replace: bool = False) -> S:
    """Return an annotation-only copy with merged or replaced metadata."""
    _validate_frame_metadata(updates)
    return self._with_annotations(metadata=updates, replace=replace)

with_channel_extra(channel, updates, *, replace=False)

Return an annotation-only copy with one channel's extra metadata updated.

Source code in wandas/core/base_frame.py
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def with_channel_extra(
    self: S,
    channel: str | int,
    updates: Mapping[str, Any],
    *,
    replace: bool = False,
) -> S:
    """Return an annotation-only copy with one channel's extra metadata updated."""
    return self._with_annotations(channel_extra={channel: updates}, replace=replace)

with_source_time_offset(value)

Return a Recipe-capable copy preserving scalar or vector call intent.

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.frame.with_source_time_offset",
    capture=_capture_source_time_offset,
    handler=_apply_source_time_offset_recipe,
    validate_params=_validate_source_time_offset_recipe_params,
)
def with_source_time_offset(self: S, value: float | Sequence[float] | NDArrayReal) -> S:
    """Return a Recipe-capable copy preserving scalar or vector call intent."""
    offsets = self._normalize_source_time_offset(value, self.n_channels)
    return self._create_new_instance(
        self._data,
        source_time_offset=offsets,
        lineage=self._required_semantic_lineage(),
    )

rename_channels(mapping)

Return a copy with channel labels renamed by index or current label.

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.channel.rename_channels",
    capture=_capture_rename_channels,
    handler=_rename_channels_recipe,
    validate_params=_validate_rename_recipe_params,
)
def rename_channels(self: S, mapping: Mapping[int | str, str]) -> S:
    """Return a copy with channel labels renamed by index or current label."""
    mapping = _normalize_rename_mapping(mapping)
    labels = self.labels
    new_labels = labels.copy()
    resolved: dict[int, str] = {}
    for key, new_label in mapping.items():
        if type(key) is int:
            if not 0 <= key < self.n_channels:
                raise KeyError(f"Channel index out of range: {key}")
            index = key
        else:
            matches = [i for i, label in enumerate(labels) if label == key]
            if not matches:
                raise KeyError(f"Channel label not found: {key!r}")
            if len(matches) > 1:
                raise ValueError(f"Channel label is ambiguous: {key!r}")
            index = matches[0]
        if index in resolved:
            raise ValueError(f"Duplicate channel rename mapping for index {index}")
        resolved[index] = new_label
        new_labels[index] = new_label
    if len(set(new_labels)) != len(new_labels):
        raise ValueError(f"Duplicate channel label after rename: {new_labels}")
    descriptors = self._borrowed_channel_metadata_descriptors()
    for descriptor, new_label in zip(descriptors, new_labels, strict=True):
        descriptor["label"] = new_label
    return self._create_new_instance(
        self._data,
        channel_metadata=descriptors,
        channel_ids=self._channel_ids,
        lineage=self._required_semantic_lineage(),
    )

get_channel(channel_idx=None, query=None, validate_query_keys=True)

Get channel(s) by index.

Parameters

channel_idx : int or sequence of int Single channel index or sequence of channel indices. Supports negative indices (e.g., -1 for the last channel). query : str, re.Pattern, callable, or dict, optional If a query is provided, use it to derive indices and ignore the positional channel_idx argument. Query to select channels based on metadata. Supported types: - str: exact label match - re.Pattern: regex search against label - callable(ChannelMetadata) -> bool: predicate on channel metadata - dict: attribute equality on ChannelMetadata (values may be re.Pattern) validate_query_keys : bool, default True If True (default), dict queries that contain unknown keys (neither model fields nor any channel extra keys) will raise KeyError. Set to False to disable this strict validation and allow callers to attempt matches without pre-validation. Returns


S New instance containing the selected channel(s).

Examples

frame.get_channel(0) # Single channel frame.get_channel([0, 2, 3]) # Multiple channels frame.get_channel((-1, -2)) # Last two channels frame.get_channel(np.array([1, 2])) # NumPy array of indices

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.frame.get_channel",
    capture=_capture_get_channel,
    handler=_apply_get_channel_recipe,
)
def get_channel(
    self: S,
    channel_idx: int | list[int] | tuple[int, ...] | npt.NDArray[np.int_] | npt.NDArray[np.bool_] | None = None,
    query: QueryType | None = None,
    validate_query_keys: bool = True,
) -> S:
    """
    Get channel(s) by index.

    Parameters
    ----------
    channel_idx : int or sequence of int
        Single channel index or sequence of channel indices.
        Supports negative indices (e.g., -1 for the last channel).
    query : str, re.Pattern, callable, or dict, optional
        If a query is provided, use it to derive indices and ignore the positional channel_idx argument.
        Query to select channels based on metadata. Supported types:
        - str: exact label match
        - re.Pattern: regex search against label
        - callable(ChannelMetadata) -> bool: predicate on channel metadata
        - dict: attribute equality on ChannelMetadata (values may be re.Pattern)
    validate_query_keys : bool, default True
        If True (default), dict queries that contain unknown keys (neither
        model fields nor any channel `extra` keys) will raise `KeyError`.
        Set to False to disable this strict validation and allow callers
        to attempt matches without pre-validation.
    Returns
    -------
    S
        New instance containing the selected channel(s).

    Examples
    --------
    >>> frame.get_channel(0)  # Single channel
    >>> frame.get_channel([0, 2, 3])  # Multiple channels
    >>> frame.get_channel((-1, -2))  # Last two channels
    >>> frame.get_channel(np.array([1, 2]))  # NumPy array of indices
    """

    if query is not None:
        indices = self._channel_indices_from_query(query, validate_query_keys)
        if not indices:
            raise KeyError(f"No channels match query: {query!r}")
    else:
        if channel_idx is None:
            raise TypeError("Either 'channel_idx' or 'query' must be provided.")
        indices = self._channel_indices(channel_idx)
    return self._select_channels(indices, self._required_semantic_lineage())

__len__()

Returns the number of channels.

Source code in wandas/core/base_frame.py
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def __len__(self) -> int:
    """
    Returns the number of channels.
    """
    return len(self._channel_metadata)

__iter__()

Yield immutable single-channel Frame selections in channel order.

Source code in wandas/core/base_frame.py
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def __iter__(self: S) -> Iterator[S]:
    """Yield immutable single-channel Frame selections in channel order."""
    for idx in range(len(self)):
        yield self[idx]

__getitem__(key)

Get channel(s) by index, label, or advanced indexing.

This method supports multiple indexing patterns similar to NumPy and pandas:

  • Single channel by index: frame[0]
  • Single channel by label: frame["ch0"]
  • Slice of channels: frame[0:3]
  • Multiple channels by indices: frame[[0, 2, 5]]
  • Multiple channels by labels: frame[["ch0", "ch2"]]
  • NumPy integer array: frame[np.array([0, 2])]
  • Boolean mask: frame[mask] where mask is a boolean array
  • Multidimensional indexing: frame[0, 100:200] (channel + axis slice)
Parameters

key : int, str, slice, list, tuple, or ndarray - int: Single channel index (supports negative indexing) - str: Single channel label - slice: Range of channels - list[int]: Multiple channel indices - list[str]: Multiple channel labels - tuple: A channel selector followed by slices for semantic axes such as frequency or time - ndarray[int]: NumPy array of channel indices - ndarray[bool]: Boolean mask for channel selection

Returns

S New instance containing the selected channel(s).

Raises

ValueError If the key length is invalid for the shape, a non-channel selector is not a slice, a time slice is stepped or reversed, or a boolean mask length doesn't match the channels. IndexError If the channel index is out of range. TypeError If the key type is invalid or list contains mixed types. KeyError If a channel label is not found.

Examples
Single channel selection

frame[0] # First channel frame["acc_x"] # By label frame[-1] # Last channel

Multiple channel selection

frame[[0, 2, 5]] # Multiple indices frame[["acc_x", "acc_z"]] # Multiple labels frame[0:3] # Slice

NumPy array indexing

frame[np.array([0, 2, 4])] # Integer array mask = np.array([True, False, True]) frame[mask] # Boolean mask

Time slicing (multidimensional)

frame[0, 100:200] # Channel 0, samples 100-200 frame[[0, 1], 100:200] # Channels 0-1, continuous sample slice

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.frame.index",
    capture=_capture_index,
    handler=_apply_index_recipe,
)
def __getitem__(
    self: S,
    key: int
    | str
    | slice
    | list[int]
    | list[str]
    | tuple[
        int | str | slice | list[int] | list[str] | npt.NDArray[np.int_] | npt.NDArray[np.bool_],
        ...,
    ]
    | npt.NDArray[np.int_]
    | npt.NDArray[np.bool_],
) -> S:
    """
    Get channel(s) by index, label, or advanced indexing.

    This method supports multiple indexing patterns similar to NumPy and pandas:

    - Single channel by index: `frame[0]`
    - Single channel by label: `frame["ch0"]`
    - Slice of channels: `frame[0:3]`
    - Multiple channels by indices: `frame[[0, 2, 5]]`
    - Multiple channels by labels: `frame[["ch0", "ch2"]]`
    - NumPy integer array: `frame[np.array([0, 2])]`
    - Boolean mask: `frame[mask]` where mask is a boolean array
    - Multidimensional indexing: `frame[0, 100:200]` (channel + axis slice)

    Parameters
    ----------
    key : int, str, slice, list, tuple, or ndarray
        - int: Single channel index (supports negative indexing)
        - str: Single channel label
        - slice: Range of channels
        - list[int]: Multiple channel indices
        - list[str]: Multiple channel labels
        - tuple: A channel selector followed by slices for semantic axes such
          as frequency or time
        - ndarray[int]: NumPy array of channel indices
        - ndarray[bool]: Boolean mask for channel selection

    Returns
    -------
    S
        New instance containing the selected channel(s).

    Raises
    ------
    ValueError
        If the key length is invalid for the shape, a non-channel selector
        is not a slice, a time slice is stepped or reversed, or a boolean mask
        length doesn't match the channels.
    IndexError
        If the channel index is out of range.
    TypeError
        If the key type is invalid or list contains mixed types.
    KeyError
        If a channel label is not found.

    Examples
    --------
    >>> # Single channel selection
    >>> frame[0]  # First channel
    >>> frame["acc_x"]  # By label
    >>> frame[-1]  # Last channel
    >>>
    >>> # Multiple channel selection
    >>> frame[[0, 2, 5]]  # Multiple indices
    >>> frame[["acc_x", "acc_z"]]  # Multiple labels
    >>> frame[0:3]  # Slice
    >>>
    >>> # NumPy array indexing
    >>> frame[np.array([0, 2, 4])]  # Integer array
    >>> mask = np.array([True, False, True])
    >>> frame[mask]  # Boolean mask
    >>>
    >>> # Time slicing (multidimensional)
    >>> frame[0, 100:200]  # Channel 0, samples 100-200
    >>> frame[[0, 1], 100:200]  # Channels 0-1, continuous sample slice
    """
    if isinstance(key, tuple) and len(key) == 1:
        key = key[0]
    lineage = self._required_semantic_lineage()
    if isinstance(key, tuple):
        return self._handle_multidim_indexing(cast(tuple[Any, ...], key))
    return self._select_channels(self._channel_indices(key), lineage)

label2index(label)

Get the index from a channel label.

Parameters

label : str Channel label.

Returns

int Corresponding index.

Raises

KeyError If the channel label is not found.

Source code in wandas/core/base_frame.py
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def label2index(self, label: str) -> int:
    """
    Get the index from a channel label.

    Parameters
    ----------
    label : str
        Channel label.

    Returns
    -------
    int
        Corresponding index.

    Raises
    ------
    KeyError
        If the channel label is not found.
    """
    for idx, ch in enumerate(self.channels):
        if ch.label == label:
            return idx
    raise KeyError(f"Channel label '{label}' not found.")

plot(plot_type='default', ax=None, **kwargs) abstractmethod

Plot the data

Source code in wandas/core/base_frame.py
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@abstractmethod
def plot(self, plot_type: str = "default", ax: "Axes | None" = None, **kwargs: Any) -> "Axes | Iterator[Axes]":
    """Plot the data"""

save(path, *, compress='gzip', overwrite=False)

Save this exact built-in Frame type as a WDF 0.4 artifact.

WDF stores the raw tensor together with the constructor state, semantic dimensions, channel calibration, metadata, and display history needed to reconstruct the same Frame type. Runtime lineage and the Dask task graph are intentionally outside the persistence boundary.

Parameters:

Name Type Description Default
path str | Path

Destination path. The .wdf suffix is appended when absent.

required
compress str | None

HDF5 dataset compression filter, or None for no compression.

'gzip'
overwrite bool

Replace an existing artifact when true.

False

Raises:

Type Description
FileExistsError

If the destination exists and overwrite is false.

TypeError

If this is not an exact supported built-in Frame type.

ValueError

If Frame state cannot be represented by the current schema.

Source code in wandas/core/base_frame.py
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def save(
    self,
    path: str | Path,
    *,
    compress: str | None = "gzip",
    overwrite: bool = False,
) -> None:
    """Save this exact built-in Frame type as a WDF 0.4 artifact.

    WDF stores the raw tensor together with the constructor state, semantic
    dimensions, channel calibration, metadata, and display history needed to
    reconstruct the same Frame type. Runtime lineage and the Dask task graph are
    intentionally outside the persistence boundary.

    Args:
        path: Destination path. The ``.wdf`` suffix is appended when absent.
        compress: HDF5 dataset compression filter, or ``None`` for no
            compression.
        overwrite: Replace an existing artifact when true.

    Raises:
        FileExistsError: If the destination exists and ``overwrite`` is false.
        TypeError: If this is not an exact supported built-in Frame type.
        ValueError: If Frame state cannot be represented by the current schema.
    """
    from wandas.io.wdf_io import save as wdf_save

    wdf_save(
        self,
        path,
        compress=compress,
        overwrite=overwrite,
    )

__array__(dtype=None, copy=None)

Implicit conversion to NumPy array

Source code in wandas/core/base_frame.py
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def __array__(self, dtype: npt.DTypeLike = None, copy: bool | None = None) -> NDArrayReal:
    """Implicit conversion to NumPy array"""
    if copy is False:
        raise ValueError("A Dask-backed Frame cannot provide a zero-copy NumPy array.")

    result = self.data
    if dtype is not None:
        result = result.astype(dtype, copy=copy is True)
    elif copy is True:
        result = result.copy()
    return cast(NDArrayReal, result)

__array_ufunc__(ufunc, method, *inputs, **kwargs)

Handle NumPy scalar-left operators without forcing eager arrays.

Source code in wandas/core/base_frame.py
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def __array_ufunc__(self, ufunc: np.ufunc, method: str, *inputs: Any, **kwargs: Any) -> Any:
    """Handle NumPy scalar-left operators without forcing eager arrays."""
    if method == "__call__" and len(inputs) == 2 and inputs[1] is self and isinstance(inputs[0], np.generic):
        reverse_method_name = self._array_ufunc_reverse_methods.get(ufunc.__name__)
        if reverse_method_name is not None:
            result = getattr(self, reverse_method_name)(inputs[0])
            return result
    array_inputs = tuple(np.asarray(input_value) if input_value is self else input_value for input_value in inputs)
    return getattr(ufunc, method)(*array_inputs, **kwargs)

visualize_graph(filename=None)

Visualize the computation graph and save it to a file.

This method creates a visual representation of the Dask computation graph. In interactive Python environments, it returns an IPython.display.Image object that can be displayed inline. In other environments, it saves the graph to a file and returns None.

Parameters

filename : str, optional Output filename for the graph image. If None, a unique filename is generated using UUID. The file is saved in the current working directory.

Returns

IPython.display.Image or None In interactive Python environments: Returns an IPython.display.Image object that can be displayed inline. In other environments: Returns None after saving the graph to file.

Notes

This method requires graphviz to be installed on your system: - Ubuntu/Debian: sudo apt-get install graphviz - macOS: brew install graphviz - Windows: Download from https://graphviz.org/download/

The graph displays operation names (e.g., 'normalize', 'lowpass_filter') making it easier to understand the processing pipeline.

Examples

import wandas as wd signal = wd.read("audio.wav") processed = signal.normalize().low_pass_filter(cutoff=1000)

In interactive environments: displays graph inline

processed.visualize_graph()

Save to specific file

processed.visualize_graph("my_graph.png")

See Also

debug_info : Print detailed debug information about the frame

Source code in wandas/core/base_frame.py
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def visualize_graph(self, filename: str | None = None) -> VisualizeReturnType:
    """
    Visualize the computation graph and save it to a file.

    This method creates a visual representation of the Dask computation graph.
    In interactive Python environments, it returns an IPython.display.Image object
    that can be displayed inline. In other environments, it saves the graph to
    a file and returns None.

    Parameters
    ----------
    filename : str, optional
        Output filename for the graph image. If None, a unique filename
        is generated using UUID. The file is saved in the current working
        directory.

    Returns
    -------
    IPython.display.Image or None
        In interactive Python environments: Returns an IPython.display.Image object
        that can be displayed inline.
        In other environments: Returns None after saving the graph to file.

    Notes
    -----
    This method requires graphviz to be installed on your system:
    - Ubuntu/Debian: `sudo apt-get install graphviz`
    - macOS: `brew install graphviz`
    - Windows: Download from https://graphviz.org/download/

    The graph displays operation names (e.g., 'normalize', 'lowpass_filter')
    making it easier to understand the processing pipeline.

    Examples
    --------
    >>> import wandas as wd
    >>> signal = wd.read("audio.wav")
    >>> processed = signal.normalize().low_pass_filter(cutoff=1000)
    >>> # In interactive environments: displays graph inline
    >>> processed.visualize_graph()
    >>> # Save to specific file
    >>> processed.visualize_graph("my_graph.png")

    See Also
    --------
    debug_info : Print detailed debug information about the frame
    """
    try:
        filename = filename or f"graph_{uuid.uuid4().hex[:8]}.png"
        return self._effective_data.visualize(filename=filename)
    except Exception as e:
        logger.warning(f"Failed to visualize the graph: {e}")
        return None

__add__(other)

Addition operator

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.add",
    binding_patterns=_FORWARD_BINARY_PATTERNS,
    capture=_capture_binary,
    handler=_binary_recipe_handler("__add__"),
)
def __add__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
    """Addition operator"""
    return self._binary_op(other, lambda x, y: x + y, "+")

__sub__(other)

Subtraction operator

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.subtract",
    binding_patterns=_FORWARD_BINARY_PATTERNS,
    capture=_capture_binary,
    handler=_binary_recipe_handler("__sub__"),
)
def __sub__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
    """Subtraction operator"""
    return self._binary_op(other, lambda x, y: x - y, "-")

__mul__(other)

Multiplication operator

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.multiply",
    binding_patterns=_FORWARD_BINARY_PATTERNS,
    capture=_capture_binary,
    handler=_binary_recipe_handler("__mul__"),
)
def __mul__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
    """Multiplication operator"""
    return self._binary_op(other, lambda x, y: x * y, "*")

__truediv__(other)

Division operator

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.divide",
    binding_patterns=_FORWARD_BINARY_PATTERNS,
    capture=_capture_binary,
    handler=_binary_recipe_handler("__truediv__"),
)
def __truediv__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
    """Division operator"""
    return self._binary_op(other, lambda x, y: x / y, "/")

__pow__(other)

Power operator

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.power",
    binding_patterns=_FORWARD_BINARY_PATTERNS,
    capture=_capture_binary,
    handler=_binary_recipe_handler("__pow__"),
)
def __pow__(self: S, other: S | int | float | complex | NDArrayReal) -> S:
    """Power operator"""
    return self._binary_op(other, lambda x, y: x**y, "**")

__radd__(other)

Reverse addition operator.

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.reverse_add",
    binding_patterns=_REVERSE_BINARY_PATTERNS,
    capture=_capture_reverse_binary,
    handler=_binary_recipe_handler("__radd__"),
)
def __radd__(self: S, other: int | float) -> S:
    """Reverse addition operator."""
    if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
        return NotImplemented
    return self._binary_operand_op(other, lambda x, y: x + y, "+", reverse=True)

__rsub__(other)

Reverse subtraction operator.

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.reverse_subtract",
    binding_patterns=_REVERSE_BINARY_PATTERNS,
    capture=_capture_reverse_binary,
    handler=_binary_recipe_handler("__rsub__"),
)
def __rsub__(self: S, other: int | float) -> S:
    """Reverse subtraction operator."""
    if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
        return NotImplemented
    return self._binary_operand_op(other, lambda x, y: x - y, "-", reverse=True)

__rmul__(other)

Reverse multiplication operator.

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.reverse_multiply",
    binding_patterns=_REVERSE_BINARY_PATTERNS,
    capture=_capture_reverse_binary,
    handler=_binary_recipe_handler("__rmul__"),
)
def __rmul__(self: S, other: int | float) -> S:
    """Reverse multiplication operator."""
    if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
        return NotImplemented
    return self._binary_operand_op(other, lambda x, y: x * y, "*", reverse=True)

__rtruediv__(other)

Reverse division operator.

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.reverse_divide",
    binding_patterns=_REVERSE_BINARY_PATTERNS,
    capture=_capture_reverse_binary,
    handler=_binary_recipe_handler("__rtruediv__"),
)
def __rtruediv__(self: S, other: int | float) -> S:
    """Reverse division operator."""
    if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
        return NotImplemented
    return self._binary_operand_op(other, lambda x, y: x / y, "/", reverse=True)

__rpow__(other)

Reverse power operator.

Source code in wandas/core/base_frame.py
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@recipe_operation(
    "wandas.operator.reverse_power",
    binding_patterns=_REVERSE_BINARY_PATTERNS,
    capture=_capture_reverse_binary,
    handler=_binary_recipe_handler("__rpow__"),
)
def __rpow__(self: S, other: int | float) -> S:
    """Reverse power operator."""
    if not self._is_supported_reverse_scalar(other) or not self._supports_base_reverse_scalar_op():
        return NotImplemented
    return self._binary_operand_op(other, lambda x, y: x**y, "**", reverse=True)

debug_info()

Output detailed debug information

Source code in wandas/core/base_frame.py
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def debug_info(self) -> None:
    """Output detailed debug information"""
    logger.debug(f"=== {self.__class__.__name__} Debug Info ===")
    logger.debug(f"Label: {self.label}")
    logger.debug(f"Shape: {self.shape}")
    logger.debug(f"Sampling rate: {self.sampling_rate} Hz")
    logger.debug(f"Operation history: {len(self.operation_history)} operations")
    try:
        effective_data = self._effective_data
        logger.debug(f"Dask graph layers: {list(effective_data.dask.layers.keys())}")
        logger.debug(f"Dask graph dependencies: {len(effective_data.dask.dependencies)}")
    except Exception as e:
        logger.debug(f"Dask graph details unavailable: {e}")
    self._debug_info_impl()
    logger.debug("=== End Debug Info ===")

print_operation_history()

Print the operation history to standard output in a readable format.

This method writes a human-friendly representation of the operation_history list to stdout. Each operation is printed on its own line with an index, the operation name (if available), and the parameters used.

Examples

cf.print_operation_history() 1: normalize {} 2: low_pass_filter {'cutoff': 1000}

Source code in wandas/core/base_frame.py
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def print_operation_history(self) -> None:
    """
    Print the operation history to standard output in a readable format.

    This method writes a human-friendly representation of the
    `operation_history` list to stdout. Each operation is printed on its
    own line with an index, the operation name (if available), and the
    parameters used.

    Examples
    --------
    >>> cf.print_operation_history()
    1: normalize {}
    2: low_pass_filter {'cutoff': 1000}
    """
    if not self.operation_history:
        print("Operation history: <empty>")
        return

    print(f"Operation history ({len(self.operation_history)}):")
    for i, record in enumerate(self.operation_history, start=1):
        # record is expected to be a dict with at least a 'operation' key
        op_name = record.get("operation") or record.get("name") or "<unknown>"
        # Copy params for display - exclude the 'operation'/'name' keys
        params = {k: v for k, v in record.items() if k not in ("operation", "name")}
        print(f"{i}: {op_name} {params}")

to_numpy()

Convert the frame data to a NumPy array.

This method is equivalent to accessing :attr:data.

Returns

T NumPy array containing the frame data.

Examples

cf = wd.read("audio.wav") data = cf.to_numpy() print(f"Shape: {data.shape}") # (n_channels, n_samples)

Source code in wandas/core/base_frame.py
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def to_numpy(self) -> T:
    """Convert the frame data to a NumPy array.

    This method is equivalent to accessing :attr:`data`.

    Returns
    -------
    T
        NumPy array containing the frame data.

    Examples
    --------
    >>> cf = wd.read("audio.wav")
    >>> data = cf.to_numpy()
    >>> print(f"Shape: {data.shape}")  # (n_channels, n_samples)
    """
    return self.data

to_tensor(framework='torch', device=None)

Convert the Dask array to a tensor in the specified framework.

Parameters

framework : str, default="torch" The ML framework to use ("torch" or "tensorflow"). device : str or None, optional Device to place the tensor on. For PyTorch, use "cpu", "cuda", "cuda:0", etc. For TensorFlow, use "/CPU:0", "/GPU:0", etc. If None, uses the default device.

Returns

torch.Tensor or tf.Tensor A tensor in the specified framework.

Raises

ImportError If the specified framework is not installed. ValueError If the framework is not supported. TypeError If self.data is not a Dask array.

Examples
PyTorch tensor on CPU

tensor = frame.to_tensor(framework="torch", device="cpu")

PyTorch tensor on GPU

tensor = frame.to_tensor(framework="torch", device="cuda:0")

TensorFlow tensor on GPU

tensor = frame.to_tensor(framework="tensorflow", device="/GPU:0")

Source code in wandas/core/base_frame.py
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def to_tensor(self, framework: str = "torch", device: str | None = None) -> Any:
    """
    Convert the Dask array to a tensor in the specified framework.

    Parameters
    ----------
    framework : str, default="torch"
        The ML framework to use ("torch" or "tensorflow").
    device : str or None, optional
        Device to place the tensor on. For PyTorch, use "cpu", "cuda", "cuda:0",
        etc. For TensorFlow, use "/CPU:0", "/GPU:0", etc. If None, uses the default
        device.

    Returns
    -------
    torch.Tensor or tf.Tensor
        A tensor in the specified framework.

    Raises
    ------
    ImportError
        If the specified framework is not installed.
    ValueError
        If the framework is not supported.
    TypeError
        If self.data is not a Dask array.

    Examples
    --------
    >>> # PyTorch tensor on CPU
    >>> tensor = frame.to_tensor(framework="torch", device="cpu")
    >>> # PyTorch tensor on GPU
    >>> tensor = frame.to_tensor(framework="torch", device="cuda:0")
    >>> # TensorFlow tensor on GPU
    >>> tensor = frame.to_tensor(framework="tensorflow", device="/GPU:0")
    """

    if framework == "torch":
        torch = require_dependency("torch", feature="tensor conversion with framework='torch'")
        numpy_data = self.to_numpy()

        # Convert NumPy array to PyTorch tensor
        tensor = torch.from_numpy(numpy_data)

        # Move to specified device if provided
        if device is not None:
            tensor = tensor.to(device)

        return tensor

    elif framework == "tensorflow":
        tf = require_dependency(
            "tensorflow",
            feature="tensor conversion with framework='tensorflow'",
        )
        numpy_data = self.to_numpy()

        # Convert NumPy array to TensorFlow tensor
        if device is not None:
            with tf.device(device):
                tensor = tf.convert_to_tensor(numpy_data)
        else:
            tensor = tf.convert_to_tensor(numpy_data)

        return tensor

    else:
        raise ValueError(
            f"Unsupported framework\n"
            f"  Got: '{framework}'\n"
            f"  Expected: 'torch' or 'tensorflow'\n"
            f"Use a supported framework for tensor conversion"
        )

to_dataframe()

Convert the frame data to a pandas DataFrame.

This method provides a common implementation for converting frame data to pandas DataFrame. Subclasses can override this method for custom behavior.

Returns

pd.DataFrame DataFrame with appropriate index and columns.

Examples

cf = wd.read("audio.wav") df = cf.to_dataframe() print(df.head())

Source code in wandas/core/base_frame.py
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def to_dataframe(self) -> "pd.DataFrame":
    """Convert the frame data to a pandas DataFrame.

    This method provides a common implementation for converting frame data
    to pandas DataFrame. Subclasses can override this method for custom behavior.

    Returns
    -------
    pd.DataFrame
        DataFrame with appropriate index and columns.

    Examples
    --------
    >>> cf = wd.read("audio.wav")
    >>> df = cf.to_dataframe()
    >>> print(df.head())
    """
    pd = require_pandas("BaseFrame.to_dataframe")

    # Get data as numpy array
    data = self.to_numpy()

    # Get column names from subclass
    columns = self._get_dataframe_columns()

    # Get index from subclass
    index = self._get_dataframe_index()

    # Create DataFrame
    if data.ndim == 1:
        # Single channel case - reshape to 2D
        df = pd.DataFrame(data.reshape(-1, 1), columns=columns, index=index)
    else:
        # Multi-channel case - transpose to (n_samples, n_channels)
        df = pd.DataFrame(data.T, columns=columns, index=index)

    return df

ChannelMetadata

The ChannelMetadata class manages metadata related to audio channels. ChannelMetadataクラスはオーディオデータのチャンネルに関連するメタデータを管理します。

wandas.core.metadata.ChannelMetadata dataclass

Metadata for a single channel.

Source code in wandas/core/metadata.py
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@dataclass(init=False)
class ChannelMetadata:
    """Metadata for a single channel."""

    label: str = ""
    calibration: ChannelCalibration = field(default_factory=ChannelCalibration)
    extra: dict[str, Any] = field(default_factory=dict)
    _initialized: bool = field(default=False, init=False, repr=False)

    _MODEL_FIELDS = frozenset({"label", "calibration", "unit", "ref", "extra"})

    def __init__(
        self,
        label: str = "",
        unit: str = "",
        ref: float | _RefUnset = _REF_UNSET,
        extra: dict[str, Any] | _ExtraUnset = _EXTRA_UNSET,
        calibration: ChannelCalibration | None = None,
    ) -> None:
        if extra is _EXTRA_UNSET:
            extra_value = {}
        else:
            extra_value = _snapshot_channel_extra(extra, preserve_mapping_type=True)

        if calibration is not None:
            if not isinstance(calibration, ChannelCalibration):
                raise TypeError("ChannelMetadata calibration must be a ChannelCalibration")
            if unit or not isinstance(ref, _RefUnset):
                raise ValueError(
                    "Conflicting channel calibration metadata\n"
                    "  Got: calibration together with unit or ref\n"
                    "  Expected: one authoritative physical-domain definition\n"
                    "Pass calibration alone, or use the legacy unit/ref arguments."
                )
            calibration_value = calibration
        else:
            calibration_value = ChannelCalibration(factor=1.0, unit=unit, ref=ref)

        object.__setattr__(self, "label", _normalize_channel_label(label))
        object.__setattr__(self, "calibration", calibration_value)
        object.__setattr__(self, "extra", extra_value)
        self.__post_init__()

    def __post_init__(self) -> None:
        if not isinstance(self.calibration, ChannelCalibration):
            raise TypeError("ChannelMetadata calibration must be a ChannelCalibration")
        object.__setattr__(self, "_initialized", True)

    @property
    def unit(self) -> str:
        """Physical unit owned by :attr:`calibration`."""
        return self.calibration.unit

    @unit.setter
    def unit(self, value: str) -> None:
        try:
            current = object.__getattribute__(self, "calibration")
        except AttributeError:
            current = ChannelCalibration()
        self.calibration = current.with_unit(value)

    @property
    def ref(self) -> float:
        """Level reference owned by :attr:`calibration`."""
        return float(self.calibration.ref)

    @ref.setter
    def ref(self, value: float) -> None:
        try:
            current = object.__getattribute__(self, "calibration")
        except AttributeError:
            current = ChannelCalibration()
        self.calibration = current.with_ref(value)

    def __setattr__(self, name: str, value: Any) -> None:
        if name == "label":
            value = _normalize_channel_label(value)
        if name == "extra":
            value = _snapshot_channel_extra(value)
        if name == "calibration" and not isinstance(value, ChannelCalibration):
            raise TypeError("ChannelMetadata calibration must be a ChannelCalibration")
        object.__setattr__(self, name, value)

    def __getitem__(self, key: str) -> Any:
        """Provide dictionary-like behavior."""
        if key in self._MODEL_FIELDS:
            return getattr(self, key)
        return self.extra.get(key)

    def __setitem__(self, key: str, value: Any) -> None:
        """Provide dictionary-like behavior."""
        if key in self._MODEL_FIELDS:
            setattr(self, key, value)
        else:
            self.extra[key] = value

    def matches_query(self, query: dict[str, Any]) -> bool:
        """Check whether this channel matches all key-value pairs in query."""
        for key, expected in query.items():
            actual = getattr(self, key, None)
            if actual is None:
                actual = self.extra.get(key)
                if actual is None:
                    return False

            if hasattr(expected, "search") and callable(expected.search):
                if not (isinstance(actual, str) and expected.search(actual)):
                    return False
            elif actual != expected:
                return False
        return True

    def to_json(self) -> str:
        """Convert to JSON with one authoritative calibration object."""
        return json.dumps(
            {
                "label": self.label,
                "calibration": self.calibration.to_dict(),
                "extra": self.extra,
            },
            indent=4,
        )

    @classmethod
    def from_json(cls, json_data: str) -> "ChannelMetadata":
        """Convert from current or legacy JSON format."""
        try:
            data = json.loads(json_data)
        except json.JSONDecodeError as e:
            raise ValueError(f"Invalid ChannelMetadata JSON: {e}") from e
        if not isinstance(data, dict):
            raise ValueError("ChannelMetadata JSON must decode to an object")
        try:
            if "calibration" in data:
                calibration_data = data.pop("calibration")
                calibration = ChannelCalibration.from_dict(calibration_data)
                if "unit" in data or "ref" in data:
                    raise ValueError("ChannelMetadata JSON must not combine calibration with legacy unit/ref fields")
                data["calibration"] = calibration
            return cls(**data)
        except (TypeError, ValueError) as e:
            raise ValueError(f"Invalid ChannelMetadata JSON object: {e}") from e

Attributes

label = '' class-attribute instance-attribute

calibration = field(default_factory=ChannelCalibration) class-attribute instance-attribute

extra = field(default_factory=dict) class-attribute instance-attribute

unit property writable

Physical unit owned by :attr:calibration.

ref property writable

Level reference owned by :attr:calibration.

Functions

__init__(label='', unit='', ref=_REF_UNSET, extra=_EXTRA_UNSET, calibration=None)

Source code in wandas/core/metadata.py
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def __init__(
    self,
    label: str = "",
    unit: str = "",
    ref: float | _RefUnset = _REF_UNSET,
    extra: dict[str, Any] | _ExtraUnset = _EXTRA_UNSET,
    calibration: ChannelCalibration | None = None,
) -> None:
    if extra is _EXTRA_UNSET:
        extra_value = {}
    else:
        extra_value = _snapshot_channel_extra(extra, preserve_mapping_type=True)

    if calibration is not None:
        if not isinstance(calibration, ChannelCalibration):
            raise TypeError("ChannelMetadata calibration must be a ChannelCalibration")
        if unit or not isinstance(ref, _RefUnset):
            raise ValueError(
                "Conflicting channel calibration metadata\n"
                "  Got: calibration together with unit or ref\n"
                "  Expected: one authoritative physical-domain definition\n"
                "Pass calibration alone, or use the legacy unit/ref arguments."
            )
        calibration_value = calibration
    else:
        calibration_value = ChannelCalibration(factor=1.0, unit=unit, ref=ref)

    object.__setattr__(self, "label", _normalize_channel_label(label))
    object.__setattr__(self, "calibration", calibration_value)
    object.__setattr__(self, "extra", extra_value)
    self.__post_init__()

__post_init__()

Source code in wandas/core/metadata.py
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def __post_init__(self) -> None:
    if not isinstance(self.calibration, ChannelCalibration):
        raise TypeError("ChannelMetadata calibration must be a ChannelCalibration")
    object.__setattr__(self, "_initialized", True)

__setattr__(name, value)

Source code in wandas/core/metadata.py
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def __setattr__(self, name: str, value: Any) -> None:
    if name == "label":
        value = _normalize_channel_label(value)
    if name == "extra":
        value = _snapshot_channel_extra(value)
    if name == "calibration" and not isinstance(value, ChannelCalibration):
        raise TypeError("ChannelMetadata calibration must be a ChannelCalibration")
    object.__setattr__(self, name, value)

__getitem__(key)

Provide dictionary-like behavior.

Source code in wandas/core/metadata.py
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def __getitem__(self, key: str) -> Any:
    """Provide dictionary-like behavior."""
    if key in self._MODEL_FIELDS:
        return getattr(self, key)
    return self.extra.get(key)

__setitem__(key, value)

Provide dictionary-like behavior.

Source code in wandas/core/metadata.py
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def __setitem__(self, key: str, value: Any) -> None:
    """Provide dictionary-like behavior."""
    if key in self._MODEL_FIELDS:
        setattr(self, key, value)
    else:
        self.extra[key] = value

matches_query(query)

Check whether this channel matches all key-value pairs in query.

Source code in wandas/core/metadata.py
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def matches_query(self, query: dict[str, Any]) -> bool:
    """Check whether this channel matches all key-value pairs in query."""
    for key, expected in query.items():
        actual = getattr(self, key, None)
        if actual is None:
            actual = self.extra.get(key)
            if actual is None:
                return False

        if hasattr(expected, "search") and callable(expected.search):
            if not (isinstance(actual, str) and expected.search(actual)):
                return False
        elif actual != expected:
            return False
    return True

to_json()

Convert to JSON with one authoritative calibration object.

Source code in wandas/core/metadata.py
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def to_json(self) -> str:
    """Convert to JSON with one authoritative calibration object."""
    return json.dumps(
        {
            "label": self.label,
            "calibration": self.calibration.to_dict(),
            "extra": self.extra,
        },
        indent=4,
    )

from_json(json_data) classmethod

Convert from current or legacy JSON format.

Source code in wandas/core/metadata.py
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@classmethod
def from_json(cls, json_data: str) -> "ChannelMetadata":
    """Convert from current or legacy JSON format."""
    try:
        data = json.loads(json_data)
    except json.JSONDecodeError as e:
        raise ValueError(f"Invalid ChannelMetadata JSON: {e}") from e
    if not isinstance(data, dict):
        raise ValueError("ChannelMetadata JSON must decode to an object")
    try:
        if "calibration" in data:
            calibration_data = data.pop("calibration")
            calibration = ChannelCalibration.from_dict(calibration_data)
            if "unit" in data or "ref" in data:
                raise ValueError("ChannelMetadata JSON must not combine calibration with legacy unit/ref fields")
            data["calibration"] = calibration
        return cls(**data)
    except (TypeError, ValueError) as e:
        raise ValueError(f"Invalid ChannelMetadata JSON object: {e}") from e

ChannelCalibration

ChannelCalibration stores the immutable recorded-to-physical factor, unit, and level reference for one channel. See the per-channel calibration learning app for list, mapping, CSV, and 100-channel examples.

wandas.core.metadata.ChannelCalibration dataclass

Immutable calibration applied to one raw signal channel.

factor converts raw samples to physical values. unit and ref describe that physical domain. A missing reference is inferred from the unit (for example, Pa uses 2e-5).

Source code in wandas/core/metadata.py
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@dataclass(frozen=True, slots=True, init=False)
class ChannelCalibration:
    """Immutable calibration applied to one raw signal channel.

    ``factor`` converts raw samples to physical values. ``unit`` and ``ref``
    describe that physical domain. A missing reference is inferred from the
    unit (for example, ``Pa`` uses ``2e-5``).
    """

    factor: float = 1.0
    unit: str = ""
    ref: float = 1.0

    def __init__(
        self,
        factor: float = 1.0,
        unit: str = "",
        ref: float | _RefUnset = _REF_UNSET,
    ) -> None:
        """Normalize values and enforce the calibration contract."""
        if isinstance(factor, bool) or not isinstance(factor, numbers.Real):
            raise TypeError(
                "Invalid channel calibration factor\n"
                f"  Got: {type(factor).__name__} ({factor!r})\n"
                "  Expected: a positive finite number\n"
                "Pass the raw-to-physical scale supplied by the sensor certificate."
            )
        normalized_factor = float(factor)
        if not math.isfinite(normalized_factor) or normalized_factor <= 0:
            raise ValueError(
                "Invalid channel calibration factor\n"
                f"  Got: {normalized_factor!r}\n"
                "  Expected: a positive finite number\n"
                "Check the certificate or calibration table before configuring the channel."
            )
        if not isinstance(unit, str):
            raise TypeError(
                "Invalid channel calibration unit\n"
                f"  Got: {type(unit).__name__} ({unit!r})\n"
                "  Expected: a string\n"
                "Pass a physical unit such as 'Pa' or 'm/s^2', or use an empty string."
            )
        normalized_unit = unit.strip()
        if unit and not normalized_unit:
            raise ValueError(
                "Invalid channel calibration unit\n"
                "  Got: a whitespace-only string\n"
                "  Expected: a physical unit or an empty string\n"
                "Remove surrounding whitespace or use ''."
            )

        if isinstance(ref, _RefUnset):
            normalized_ref = float(unit_to_ref(normalized_unit)) if normalized_unit else 1.0
        else:
            if isinstance(ref, bool) or not isinstance(ref, numbers.Real):
                raise TypeError(
                    "Invalid channel calibration reference\n"
                    f"  Got: {type(ref).__name__} ({ref!r})\n"
                    "  Expected: a positive finite number\n"
                    "Pass the reference value used for level conversion."
                )
            normalized_ref = float(ref)
            if not math.isfinite(normalized_ref) or normalized_ref <= 0:
                raise ValueError(
                    "Invalid channel calibration reference\n"
                    f"  Got: {normalized_ref!r}\n"
                    "  Expected: a positive finite number\n"
                    "Check the physical reference for this channel."
                )

        object.__setattr__(self, "factor", normalized_factor)
        object.__setattr__(self, "unit", normalized_unit)
        object.__setattr__(self, "ref", normalized_ref)

    def with_factor(self, factor: float) -> "ChannelCalibration":
        """Return this physical domain with a replacement factor."""
        return ChannelCalibration(factor=factor, unit=self.unit, ref=self.ref)

    def with_unit(self, unit: str) -> "ChannelCalibration":
        """Replace the unit and reset ``ref`` to that unit's default.

        The calibration factor is preserved. Chain ``with_ref()`` after this
        method when the new unit needs a non-default reference.
        """
        return ChannelCalibration(factor=self.factor, unit=unit)

    def with_ref(self, ref: float) -> "ChannelCalibration":
        """Return a replacement reference preserving factor and unit."""
        return self._with_ref(ref)

    def _with_unit(self, unit: str) -> "ChannelCalibration":
        """Return a private domain replacement using the legacy unit/ref rule."""
        return self.with_unit(unit)

    def _with_ref(self, ref: float) -> "ChannelCalibration":
        """Return a private reference replacement preserving factor and unit."""
        return ChannelCalibration(factor=self.factor, unit=self.unit, ref=ref)

    def to_dict(self) -> dict[str, float | str]:
        """Return a JSON-safe snapshot."""
        return {"factor": self.factor, "unit": self.unit, "ref": self.ref}

    @classmethod
    def from_dict(cls, value: object) -> "ChannelCalibration":
        """Decode an exact calibration snapshot."""
        if not isinstance(value, Mapping) or set(value) != {"factor", "unit", "ref"}:
            raise ValueError(
                "Invalid channel calibration snapshot\n"
                f"  Got: {value!r}\n"
                "  Expected: factor, unit, and ref fields\n"
                "Use ChannelCalibration.to_dict() when serializing calibration values."
            )
        return cls(
            factor=value["factor"],  # ty: ignore[invalid-argument-type]
            unit=value["unit"],  # ty: ignore[invalid-argument-type]
            ref=value["ref"],  # ty: ignore[invalid-argument-type]
        )

Attributes

factor = 1.0 class-attribute instance-attribute

unit = '' class-attribute instance-attribute

ref = 1.0 class-attribute instance-attribute

Functions

__init__(factor=1.0, unit='', ref=_REF_UNSET)

Normalize values and enforce the calibration contract.

Source code in wandas/core/metadata.py
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def __init__(
    self,
    factor: float = 1.0,
    unit: str = "",
    ref: float | _RefUnset = _REF_UNSET,
) -> None:
    """Normalize values and enforce the calibration contract."""
    if isinstance(factor, bool) or not isinstance(factor, numbers.Real):
        raise TypeError(
            "Invalid channel calibration factor\n"
            f"  Got: {type(factor).__name__} ({factor!r})\n"
            "  Expected: a positive finite number\n"
            "Pass the raw-to-physical scale supplied by the sensor certificate."
        )
    normalized_factor = float(factor)
    if not math.isfinite(normalized_factor) or normalized_factor <= 0:
        raise ValueError(
            "Invalid channel calibration factor\n"
            f"  Got: {normalized_factor!r}\n"
            "  Expected: a positive finite number\n"
            "Check the certificate or calibration table before configuring the channel."
        )
    if not isinstance(unit, str):
        raise TypeError(
            "Invalid channel calibration unit\n"
            f"  Got: {type(unit).__name__} ({unit!r})\n"
            "  Expected: a string\n"
            "Pass a physical unit such as 'Pa' or 'm/s^2', or use an empty string."
        )
    normalized_unit = unit.strip()
    if unit and not normalized_unit:
        raise ValueError(
            "Invalid channel calibration unit\n"
            "  Got: a whitespace-only string\n"
            "  Expected: a physical unit or an empty string\n"
            "Remove surrounding whitespace or use ''."
        )

    if isinstance(ref, _RefUnset):
        normalized_ref = float(unit_to_ref(normalized_unit)) if normalized_unit else 1.0
    else:
        if isinstance(ref, bool) or not isinstance(ref, numbers.Real):
            raise TypeError(
                "Invalid channel calibration reference\n"
                f"  Got: {type(ref).__name__} ({ref!r})\n"
                "  Expected: a positive finite number\n"
                "Pass the reference value used for level conversion."
            )
        normalized_ref = float(ref)
        if not math.isfinite(normalized_ref) or normalized_ref <= 0:
            raise ValueError(
                "Invalid channel calibration reference\n"
                f"  Got: {normalized_ref!r}\n"
                "  Expected: a positive finite number\n"
                "Check the physical reference for this channel."
            )

    object.__setattr__(self, "factor", normalized_factor)
    object.__setattr__(self, "unit", normalized_unit)
    object.__setattr__(self, "ref", normalized_ref)

with_factor(factor)

Return this physical domain with a replacement factor.

Source code in wandas/core/metadata.py
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def with_factor(self, factor: float) -> "ChannelCalibration":
    """Return this physical domain with a replacement factor."""
    return ChannelCalibration(factor=factor, unit=self.unit, ref=self.ref)

with_unit(unit)

Replace the unit and reset ref to that unit's default.

The calibration factor is preserved. Chain with_ref() after this method when the new unit needs a non-default reference.

Source code in wandas/core/metadata.py
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def with_unit(self, unit: str) -> "ChannelCalibration":
    """Replace the unit and reset ``ref`` to that unit's default.

    The calibration factor is preserved. Chain ``with_ref()`` after this
    method when the new unit needs a non-default reference.
    """
    return ChannelCalibration(factor=self.factor, unit=unit)

with_ref(ref)

Return a replacement reference preserving factor and unit.

Source code in wandas/core/metadata.py
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def with_ref(self, ref: float) -> "ChannelCalibration":
    """Return a replacement reference preserving factor and unit."""
    return self._with_ref(ref)

to_dict()

Return a JSON-safe snapshot.

Source code in wandas/core/metadata.py
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def to_dict(self) -> dict[str, float | str]:
    """Return a JSON-safe snapshot."""
    return {"factor": self.factor, "unit": self.unit, "ref": self.ref}

from_dict(value) classmethod

Decode an exact calibration snapshot.

Source code in wandas/core/metadata.py
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@classmethod
def from_dict(cls, value: object) -> "ChannelCalibration":
    """Decode an exact calibration snapshot."""
    if not isinstance(value, Mapping) or set(value) != {"factor", "unit", "ref"}:
        raise ValueError(
            "Invalid channel calibration snapshot\n"
            f"  Got: {value!r}\n"
            "  Expected: factor, unit, and ref fields\n"
            "Use ChannelCalibration.to_dict() when serializing calibration values."
        )
    return cls(
        factor=value["factor"],  # ty: ignore[invalid-argument-type]
        unit=value["unit"],  # ty: ignore[invalid-argument-type]
        ref=value["ref"],  # ty: ignore[invalid-argument-type]
    )