sort()方法 | sorted()函數 | __call__()方法 | Python

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#     sort()方法與sorted()函數的區別：#     sort()方法是在原可迭代對象直接修改；#     sorted()函數是返回一個新的可迭代對象；# 例子：根據列表中哪個資料更靠近10來排序；# 1.lambda()>> list_first = [1,4,7,9,33,22,55,77]>> list_first.sort(key=lambda x:abs(x-10))>> print(list_first)>> [9, 7, 4, 1, 22, 33, 55, 77]>> list_second = [1,4,7,9,33,22,55,77]>> sorted(list_second, key=lambda x:abs(x-10))>> [9, 7, 4, 1, 22, 33, 55, 77]# 2.自訂函數>> def which_closed(x):>>     return abs(x-10)>> list_first = [1,4,7,9,33,22,55,77]>> list_first.sort(key=which_closed)>> print(list_first)>> [9, 7, 4, 1, 22, 33, 55, 77]# 3.類類比函數 | __call__()>> class WhichClosed(object):>>     def __init__(self,select_num):>>         self.select_num = select_num>>     def __call__(self,x):>>         return abs(x-self.select_num)>> list_first = [1,4,7,9,33,22,55,77]>> list_first.sort(key=WhichClosed(10))>> print(list_first)>> [9, 7, 4, 1, 22, 33, 55, 77]# __call__()作用：使對象變成可調用介面>> class WhichClosed(object):>>     def __init__(self,select_num):>>         self.select_num = select_num>>     def __call__(self,x):>>         return abs(x-self.select_num)>> obj = WhichClosed(10)  # 執行個體化對象>> obj(2)  # 對象加上小括弧時，對象內部調用__call__()方法；>> 8

 

sort()方法 | sorted()函數 | __call__()方法 | Python