def compute_gcvf(sdam: float, scdm: float) -> float:
    """
    Compute the goodness of class variance fit (GCVF).
    :param sdam: Sum of squared deviations for array mean (SDAM)
    :param scdm: Sum of squared class devations from mean (SCDM)
    :return: GCVF
    Sources:
        https://arxiv.org/abs/2005.01653
        https://medium.com/analytics-vidhya/jenks-natural-breaks-best-range-finder-algorithm-8d1907192051
    """
    return (sdam - scdm) / sdam