python list dict util (分割，分组)

1.list数据分割为多个小列表  （java   lists.partition）

2. 分组

import itertools

def partition(mylist, size):
    """
    :param mylist: 需要分割的列表
    :param size: 每几个分割一起
    :return: [[],[]]
    """
    return [mylist[i:i + size] for i in range(0, len(mylist), size)]

#
def groupby(mylist,key):
    """
    :param mylist: eg: [{"user":"sea","age":"23"},{"user":"sea1","age":"22"}]
    :param key:  eg: lambda x:x["user"]  or lambda d:d.x
    :return:
    """
    result = {}
    # lstg = groupby(mylist,key=lambda x:x['no'])
    lstg = itertools.groupby(mylist, key= key)
    for (key, group) in lstg:
        result[key] = list(group)
    return result

if __name__ == '__main__':
    # 分割
    l = [i for i in range(15)]
    partition1 = partition(l, 3)
    print(partition1)

去重： 思路其实就是先把ids变为[[], 1,2,3,......] ,然后在利用reduce的特性

def distinc(my_list):
    return reduce(lambda x, y: x if y in x else x + [y], [[]] + my_list)

过滤：

    my_list = []
    my_list.append({"sea1": 1,"age":2})
    my_list.append({"sea1": 2,"age":2})
    my_list.append({"sea1": 3,"age":2})
    a = itertools.filterfalse(lambda x: x["sea1"]==2, my_list)
    print(list(a))

result： [{'sea1': 1, 'age': 2}, {'sea1': 3, 'age': 2}]