数组 python 中的进程特定元素

Question

我从 Internet 中获得的已处理数据中复制了数组，结果是data=[[655.0, 48.77, 6.0, '1'], 0.0, [655.0, 48.77, 5.0, '1'], 1.0, [657.0, 49.25, 5.0, '4'], 2.2870067774276484, [657.0, 49.25, 1.0, '1'], 5.40651458890106, [657.0, 49.25, 1.0, '5'], 5.40651458890106]

我只是混淆了我如何读取该数组。 我想复制一组数据成为一个新的

new = [['1',0.0],['1',1.0],['4',2.287006],['1',5.4065145],['5',5.4065145]]

最良好的问候。

Answer 1

让我们假设您处理数据结构的恒定顺序，例如您在示例中提供的列表。

如果我理解得很好：

你得到一个嵌套列表和一些浮点数的输入列表。

[ [ A, B, C, D ], somefloat, [A, B, C, D ] somefloat ]

然后您尝试获取嵌套列表的列表，该列表采用第一个嵌套列表的最后一个元素并将其与下一个浮点数组合成一个新的嵌套列表，如下所示：

[ [D, somefloat], [D, somefloat] ]

一种解决方案可能是使用列表理解，如下所示：

data=[[655.0, 48.77, 6.0, '1'], 0.0, [655.0, 48.77, 5.0, '1'], 1.0, [657.0, 49.25, 5.0, '4'], 2.2870067774276484, [657.0, 49.25, 1.0, '1'], 5.40651458890106, [657.0, 49.25, 1.0, '5'], 5.40651458890106]

newdata = [[data[i][-1], data[i +1]] for i in range(0, len(data), 2)]
print(newdata)

Output

[['1', 0.0], ['1', 1.0], ['4', 2.2870067774276484], ['1', 5.40651458890106], ['5', 5.40651458890106]]

让我们分解一下：

for i in range(0, len(data), 2) 
# will iterate through the first list, the range method here (starts from 0 to the length of the input list) will return the current index as "i" with step of two, for each iteration.

[data[i][-1]
#will take the current item (which is a nested list) and extract from it the last element, feel free to change the -1 by any index of the element you desire (if you decide to finally go with the third element, so change the -1 -which mean the last element- by 2 -which is the third element


data[i +1]
# will take the next element (which is the float number)

[data[i][-1], data[i +1]
# will put them in a nested list (feel free to use tuple or dict if you want to output another kind of nested data structure)