filter和map的區別

相同點：filter 和 map 都是對數組的操作，均返回一個新的數組

不同點：filter是滿足條件的留下，是對原數組的過濾；map則是對原數組的加工，映射成一對一映射的新數組

 

number = [1,2,44,38,58,96,47]
new_list = list(filter(lambda x: (x%2 == 0),number))
print(number)
print(new_list)

my_list = [1, 5, 4, 6, 8, 11, 3, 12]
new_list = list(map(lambda x: x * 2, my_list))
print(my_list)
print(new_list)

[1, 2, 44, 38, 58, 96, 47]
[2, 44, 38, 58, 96]
[1, 5, 4, 6, 8, 11, 3, 12]
[2, 10, 8, 12, 16, 22, 6, 24]