Utils.py 文件源码

def _prob_no_occurrence(
        sample_size,
        subsample_size,
        sample_freq,
        num_subsamples
    ):
    """Compute the probability that an type with a given probability does not
    occur in a subsample of given size drawn from a population of a given size.
    """
    if sample_freq > sample_size - subsample_size:
        return 0
    else:
        return binom(
            sample_size-sample_freq,
            subsample_size,
            exact=True
        ) / num_subsamples