python - 我怎样才能把这个字符串分开？

Question

我试图在有一个完整的 2 位数字被空格包围的地方之前拆分字符串。最终我希望它能在 Python 中工作，但我一直在使用 sed 工作台，但我无法弄清楚。

我的测试数据是这样的:

13 13 13 13 13 9:07.18 9:12.09 9:15.65
14 14 14 2:04.86 2:05.99 2:06.87 14 4:21.51 4:23.51 4:25.00 14 8:56.28 9:01.09 9:04.58
15 15 57.18 57.61 57.95 15 2:02.61 2:03.72 2:04.58 15 4:17.31 4:19.28 4:20.75 15 8:47.15 8:51.87 8:55.30
16 16 56.34 56.76 57.09 16 2:00.69 2:01.78 2:02.63 16 4:13.75 4:15.69 4:17.14 16 8:39.71 8:44.37 8:47.75
17 25.69 25.85 25.99 17 55.62 56.03 56.36 17 1:59.07 2:00.15 2:00.99 17 4:10.76 4:12.69 4:14.11 17 8:33.73 8:38.34 8:41.68
18 25.43 25.59 25.73 18 55.01 55.42 55.74 18 1:57.74 1:58.81 1:59.63 18 4:08.34 4:10.24 4:11.66 18 8:33.73 8:37.04
19 25.20 25.36 25.49 19 54.50 54.91 55.23 19 1:57.74 1:58.56 19 4:08.34 4:09.74 19 8:33.73

我希望它像这样拆分(注意逗号“,”的位置):

13, 13, 13, 13, 13 9:07.18 9:12.09 9:15.65
14, 14, 14 2:04.86 2:05.99 2:06.87, 14 4:21.51 4:23.51 4:25.00, 14 8:56.28 9:01.09 9:04.58
15, 15 57.18 57.61 57.95, 15 2:02.61 2:03.72 2:04.58, 15 4:17.31 4:19.28 4:20.75, 15 8:47.15 8:51.87 8:55.30
16, 16 56.34 56.76 57.09, 16 2:00.69 2:01.78 2:02.63, 16 4:13.75 4:15.69 4:17.14, 16 8:39.71 8:44.37 8:47.75
17 25.69 25.85 25.99, 17 55.62 56.03 56.36, 17 1:59.07 2:00.15 2:00.99, 17 4:10.76 4:12.69 4:14.11, 17 8:33.73 8:38.34 8:41.68
18 25.43 25.59 25.73, 18 55.01 55.42 55.74, 18 1:57.74 1:58.81 1:59.63, 18 4:08.34 4:10.24 4:11.66, 18 8:33.73 8:37.04
19 25.20 25.36 25.49, 19 54.50 54.91 55.23, 19 1:57.74 1:58.56, 19 4:08.34 4:09.74, 19 8:33.73

上面的数据相当规则，因为两位整数在 [13,19] 范围内，但我应该期望的范围是 [10,99]。

有人可以建议一种执行上述转换的方法吗？我使用正则表达式已经有一段时间了，但我无法涵盖所有​​情况。

Answer 1

前瞻断言 (?=...)可以解决这个问题:

>>> a = """13 13 13 13 13 9:07.18 9:12.09 9:15.65
14 14 14 2:04.86 2:05.99 2:06.87 14 4:21.51 4:23.51 4:25.00 14 8:56.28 9:01.09 9:04.58
15 15 57.18 57.61 57.95 15 2:02.61 2:03.72 2:04.58 15 4:17.31 4:19.28 4:20.75 15 8:47.15 8:51.87 8:55.30
16 16 56.34 56.76 57.09 16 2:00.69 2:01.78 2:02.63 16 4:13.75 4:15.69 4:17.14 16 8:39.71 8:44.37 8:47.75
17 25.69 25.85 25.99 17 55.62 56.03 56.36 17 1:59.07 2:00.15 2:00.99 17 4:10.76 4:12.69 4:14.11 17 8:33.73 8:38.34 8:41.68
18 25.43 25.59 25.73 18 55.01 55.42 55.74 18 1:57.74 1:58.81 1:59.63 18 4:08.34 4:10.24 4:11.66 18 8:33.73 8:37.04
19 25.20 25.36 25.49 19 54.50 54.91 55.23 19 1:57.74 1:58.56 19 4:08.34 4:09.74 19 8:33.73"""

>>> print(re.sub("(\d{2}) (?=\d{2}( |$))","\g<1>, ", a))
13, 13, 13, 13, 13 9:07.18 9:12.09 9:15.65
14, 14, 14 2:04.86 2:05.99 2:06.87, 14 4:21.51 4:23.51 4:25.00, 14 8:56.28 9:01.09 9:04.58
15, 15 57.18 57.61 57.95, 15 2:02.61 2:03.72 2:04.58, 15 4:17.31 4:19.28 4:20.75, 15 8:47.15 8:51.87 8:55.30
16, 16 56.34 56.76 57.09, 16 2:00.69 2:01.78 2:02.63, 16 4:13.75 4:15.69 4:17.14, 16 8:39.71 8:44.37 8:47.75
17 25.69 25.85 25.99, 17 55.62 56.03 56.36, 17 1:59.07 2:00.15 2:00.99, 17 4:10.76 4:12.69 4:14.11, 17 8:33.73 8:38.34 8:41.68
18 25.43 25.59 25.73, 18 55.01 55.42 55.74, 18 1:57.74 1:58.81 1:59.63, 18 4:08.34 4:10.24 4:11.66, 18 8:33.73 8:37.04
19 25.20 25.36 25.49, 19 54.50 54.91 55.23, 19 1:57.74 1:58.56, 19 4:08.34 4:09.74, 19 8:33.73

因此，正则表达式。你需要的是(\d{2}) (?=\d{2}( |$))这意味着:

1. (\d{2}) => 在第 1 组中存储 2 个数字并匹配一个额外的空格。
2. (?=\d{2}( |$)) => 匹配 2 个数字和 1 个空格或 EOL，但不要消耗它们。

这里的关键是不消费第二个匹配的组，下次应用子功能时会再次处理。最后，\g<1>,将用相同的数字和附加的 , 替换 1. .