在python中過濾填充為None的元組列表

Question

假設我有一個如下的元組列表：

my_list = [(2, 3), (3, None), (None, None), (3, 4), (None, 2)]

我如何過濾此列表以：

1. 刪除所有包含至少一個 None元組
2. 僅刪除兩個值都為None的元組

因此，每種情況下的結果應為：

1. [(2, 3), (3, 4)]
2. [(2, 3), (3, None), (3, 4), (None, 2)]

Answer 1

使用列表推導過濾您的特定條件：

no_none = [t for t in my_list if None not in t]
some_none = [t for t in my_list if t != (None, None)]

請注意，過濾會選擇不符合您的條件的元素，因此第一個選擇不包含None的所有元組，第二個選擇不等於(None, None)元組的所有元組。

演示：

>>> my_list = [(2, 3), (3, None), (None, None), (3, 4), (None, 2)]
>>> [t for t in my_list if None not in t]
[(2, 3), (3, 4)]
>>> [t for t in my_list if t != (None, None)]
[(2, 3), (3, None), (3, 4), (None, 2)]

Answer 2

您可以使用all來確保all都不為None ，並且可以對表達式使用any ：any值都不為None 。

>>> my_list = [(2,3), (3,None), (None,None), (3,4), (None,2)]
>>> filter(lambda x:all(i is not None for i in x), my_list)
[(2, 3), (3, 4)]
>>> filter(lambda x:any(i is not None for i in x), my_list)
[(2, 3), (3, None), (3, 4), (None, 2)]