def __init__(self, add_small_diag=True):
        """Initialize the object.

        Args:
            add_small_diag (bool, optional): For signals with truly constant
                segments, the covariance matrix is badly conditioned, so we add
                a small diagonal matrix. Defaults to True.
        """
        self.signal = None
        self.min_size = 2
        self.add_small_diag = add_small_diag
        if add_small_diag:
            warnings.warn(
                "New behaviour in v1.1.5: "
                "a small bias is added to the covariance matrix to cope with truly "
                "constant segments (see PR#198).",
                UserWarning,
            )
Initialize the object.

        Args:
            add_small_diag (bool, optional): For signals with truly constant
                segments, the covariance matrix is badly conditioned, so we add
                a small diagonal matrix. Defaults to True.
        
src/ruptures/costs/costnormal.py