Python——list返回最大的K个元素的索引

自定义的一个有用的Python方法

返回最大的K个值的索引

引用自Stack Overflow

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def get_top_k_indexes_of_list(target_list, k, is_max=True, min_value=None):
    """
    get the top k indexes of elements in list
    Example:
    Problem: I have a list say a = [5,3,1,4,10],
            and I need to get a index of top two values of the list viz 5 and 10.
            Is there a one-liner that python offers for such a case?
    Usage: get_top_k_indexes_of_list(target_list=a, k=2, is_max=True)
    link: https://stackoverflow.com/questions/13070461/get-index-of-the-top-n-values-of-a-list-in-python
    :param target_list: target list
    :param k: the number of indexes
    :param is_max: True means max else False means min
    :param min_value: if min_value is not None
            filter the indexes whose value less than or equals to min_value
    :return: a list of indexes
    """
    indexes = sorted(range(len(target_list)), key=lambda i: target_list[i], reverse=is_max)[:k]
    result = list()
    if min_value is not None:
        for index in indexes:
            if target_list[index] <= min_value:
                break
            result.append(index)
    else:
        result = indexes
    return result

一次性索引出多个元素

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def get_elements_from_list(target_list, indexes):
    """
    get elements from target_list by indexes
    :param target_list: target list
    :param indexes: a list of indexes
    :return: a list of elements
    """
    elements = [target_list[i] for i in indexes]
    return elements