def _increase_reg(reg: float) -> float:
    """
    Increase regularization factor by factor of 10.

    Parameters
    ----------
    reg: float
        Current regularization factor.

    Returns
    -------
    reg : float
        Increased regularization
    """
    if reg == 0:
        reg = 1e-06
    else:
        reg = reg * 10
    return reg