使用 Sqlite,select .. from
命令会返回结果 output
,它会打印:
With Sqlite, a select .. from
command returns the results output
, which prints:
>>print output
[(12.2817, 12.2817), (0, 0), (8.52, 8.52)]
这似乎是一个元组列表.我想将 output
转换为一个简单的列表:
It seems to be a list of tuples. I would like to either convert output
to a simple list:
[12.2817, 12.2817, 0, 0, 8.52, 8.52]
或 2x3 矩阵:
12.2817 12.2817
0 0
8.52 8.52
通过output[i][j]
flatten 命令对第一个选项不起作用,我不知道第二个...
The flatten command does not do the job for the 1st option, and I have no idea for the second one...
我们将不胜感激快速的解决方案,因为实际数据要大得多.
A fast solution would be appreciated, as the real data is much bigger.
迄今为止发布的最快(和最短)的解决方案:
By far the fastest (and shortest) solution posted:
list(sum(output, ()))
比 itertools
解决方案快约 50%,比 map
解决方案快约 70%.
About 50% faster than the itertools
solution, and about 70% faster than the map
solution.
这篇关于变换“元组列表";放入一个平面列表或矩阵的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持跟版网!