Question

我有两个号码x和y。例如x为1.5，y为1.5 我需要创建一个包含8个不同值的列表列表。

[[0.5,0.5],[0.5,1.5],[0.5,2.5],
[1.5,0.5],[1.5,1.5],[1.5,2.5],
[2.5,0.5],[2.5,1.5],[2.5,2.5]]

[1.5,1.5] #needs to be removed from the above list.

如何使用不同的x和y值在python 3中执行此操作？ x和y将始终为1到10之间的数字。但它们将为1.5或2.5或3.5等。

Answer 1

尝试使用以下列表理解：

items = [[a, b] for a in items for b in items if x != a or y != b]

因此：

>>> x = 1.5
>>> y = 1.5
>>> items = [x-1, x, x+1]
>>> items = [[a, b] for a in items for b in items if x != a or y != b]
>>> items 
[[0.5, 0.5], [0.5, 1.5], [0.5, 2.5], [1.5, 0.5], [1.5, 2.5], [2.5, 0.5], [2.5, 1.5], [2.5, 2.5]]
>>>

编辑：

或者，如果列表理解太混乱，您可以将其更改为嵌套的for循环：

for i in items:
    for j in items:
        if i != x or j != y:
            cp.append([i, j])

运行如下：

>>> x = 1.5
>>> y = 1.5
>>> items = [x-1, x, x+1]
>>> cp = []
>>> for i in items:
...     for j in items:
...         if i != x or j != y:
...             cp.append([i, j])
... 
>>> items = cp
>>> items
[[0.5, 0.5], [0.5, 1.5], [0.5, 2.5], [1.5, 0.5], [1.5, 2.5], [2.5, 0.5], [2.5, 1.5], [2.5, 2.5]]
>>>

Answer 2

试试这个：

values = [0.5, 1.5, 2.5]
[[x, y] for x in values for y in values if x <> y]

输出：

[[0.5, 1.5], [0.5, 2.5], [1.5, 0.5], [1.5, 2.5], [2.5, 0.5], [2.5, 1.5]]

Answer 3

查看this question。

要从列表中删除：

list_to_remove = [x, y]
list_of_lists = [[0.5,0.5],[0.5,1.5],[0.5,2.5],
                [1.5,0.5],[1.5,1.5],[1.5,2.5],
                [2.5,0.5],[2.5,1.5],[2.5,2.5]]
list_of_lists.remove(list_to_remove)

请注意，如果list_to_remove不在list_of_lists，则会引发异常。要抓住这个，你需要：

list_to_remove = [x, y]
list_of_lists = [[0.5,0.5],[0.5,1.5],[0.5,2.5],
                [1.5,0.5],[1.5,1.5],[1.5,2.5],
                [2.5,0.5],[2.5,1.5],[2.5,2.5]]

try:
    list_of_lists.remove(list_to_remove)
except:
    print "{0} is not in list_of_lists".format(str(list_to_remove))

创建具有两个不同数字的列表

3 个答案:

编辑：