in clearbox/features.py [0:0]
def evaluate(self, signal_data: pd.DataFrame) -> npt.NDArray[float]:
"""Evaluate the node on `signal_data`.
Args:
signal_data: `pd.DataFrame` of signal values.
Returns:
Array of results as floats.
"""
if signal_data.empty:
raise ValueError("`signal_data` should not be empty.")
return np.full(signal_data.shape[0], self._value)