Question

我想创建一个包含三个值的数字列表，并希望覆盖0到3之间的每个组合。例如：

0, 0, 0
0, 0, 1
...
1, 0, 3
1, 1, 3

一直到3, 3, 3。

有没有比使用多个for循环更好的方法呢？

以下是我使用的代码：

for i in range (0, 4):
    for x in range (0, 4):
        for t in range (0, 4):
        assign = [i, x, t]

Answer 1

通常itertools.product：

list(itertools.product(range(4), repeat=3))

Answer 2

您可以使用itertools.product：

>>> from itertools import product
>>> list(product({0, 1, 2, 3}, repeat=3))
[(0, 0, 0), (0, 0, 1), (0, 0, 2), (0, 0, 3), (0, 1, 0), (0, 1, 1), (0, 1, 2), (0, 1, 3), (0, 2, 0), (0, 2, 1), (0, 2, 2), (0, 2, 3), (0, 3, 0), (0, 3, 1), (0, 3, 2), (0, 3, 3), (1, 0, 0), (1, 0, 1), (1, 0, 2), (1, 0, 3), (1, 1, 0), (1, 1, 1), (1, 1, 2), (1, 1, 3), (1, 2, 0), (1, 2, 1), (1, 2, 2), (1, 2, 3), (1, 3, 0), (1, 3, 1), (1, 3, 2), (1, 3, 3), (2, 0, 0), (2, 0, 1), (2, 0, 2), (2, 0, 3), (2, 1, 0), (2, 1, 1), (2, 1, 2), (2, 1, 3), (2, 2, 0), (2, 2, 1), (2, 2, 2), (2, 2, 3), (2, 3, 0), (2, 3, 1), (2, 3, 2), (2, 3, 3), (3, 0, 0), (3, 0, 1), (3, 0, 2), (3, 0, 3), (3, 1, 0), (3, 1, 1), (3, 1, 2), (3, 1, 3), (3, 2, 0), (3, 2, 1), (3, 2, 2), (3, 2, 3), (3, 3, 0), (3, 3, 1), (3, 3, 2), (3, 3, 3)]
>>>

Answer 3

您可以使用itertools.product()功能：

from itertools import product

for i, x, t in product(range(4), repeat=3):
    print (i, x, t)

演示：

>>> from itertools import product
>>> for i, x, t in product(range(4), repeat=3):
...     print (i, x, t)
... 
(0, 0, 0)
(0, 0, 1)
(0, 0, 2)
(0, 0, 3)
(0, 1, 0)
# ... truncated for readability ...
(3, 2, 3)
(3, 3, 0)
(3, 3, 1)
(3, 3, 2)
(3, 3, 3)

Answer 4

itertools.product()是一个很好的解决方案，但是如果你想要一个列表而不是元组列表，你可以使用它：

[ [x,y,z] for x,y,z in itertools.product(range(4), repeat=3)]

或等效列表理解：

[ [x,y,z] for x in range(0,4)
            for y in range(0,4)
                for z in range(0,4)]

创建组合列表

4 个答案: