如何將列表（矩陣）拆分爲其他列表？

Question

我不知道怎麼的10x10矩陣轉換成的5x5四個矩陣，例如：

[[10, 11, 12, 13, 14, 15, 16, 17, 18, 19], # matrix 10x10 
[20, 21, 22, 23, 24, 25, 26, 27, 28, 29], 
[30, 31, 32, 33, 34, 35, 36, 37, 38, 39], 
[40, 41, 42, 43, 44, 45, 46, 47, 48, 49], 
[50, 51, 52, 53, 54, 55, 56, 57, 58, 59], 
[60, 61, 62, 63, 64, 65, 66, 67, 68, 69], 
[10, 11, 12, 13, 14, 15, 16, 17, 18, 19], 
[20, 21, 22, 23, 24, 25, 26, 27, 28, 29], 
[30, 31, 32, 33, 34, 35, 36, 37, 38, 39], 
[40, 41, 42, 43, 44, 45, 46, 47, 48, 49]] 

我需要轉換成這樣：

[[10, 11, 12, 13, 14] # 4 like this with the other numbers too 
[20, 21, 22, 23, 24] 
[30, 31, 32, 33, 34] 
[40, 41, 42, 43, 44] 
[50, 51, 52, 53, 54]] 

Answer 1

您可以使用slicing和list comprehension：

>>> matrix = \ 
... [[10, 11, 12, 13, 14, 15, 16, 17, 18, 19], 
... [20, 21, 22, 23, 24, 25, 26, 27, 28, 29], 
... [30, 31, 32, 33, 34, 35, 36, 37, 38, 39], 
... [40, 41, 42, 43, 44, 45, 46, 47, 48, 49], 
... [50, 51, 52, 53, 54, 55, 56, 57, 58, 59], 
... [60, 61, 62, 63, 64, 65, 66, 67, 68, 69], 
... [10, 11, 12, 13, 14, 15, 16, 17, 18, 19], 
... [20, 21, 22, 23, 24, 25, 26, 27, 28, 29], 
... [30, 31, 32, 33, 34, 35, 36, 37, 38, 39], 
... [40, 41, 42, 43, 44, 45, 46, 47, 48, 49]] 
>>> from pprint import pprint 
>>> pprint([x[:5] for x in matrix[:5]]) 
[[10, 11, 12, 13, 14], 
[20, 21, 22, 23, 24], 
[30, 31, 32, 33, 34], 
[40, 41, 42, 43, 44], 
[50, 51, 52, 53, 54]] 
>>> 

sequence[:5]獲取前五項目。因此，matrix[:5]獲得matrix中的前五個子列表，x[:5]獲得每個子列表中的前五個子列表。 pprint.pprint僅用於格式化輸出。