假设我有这个文件：
1
17:02,111
Problem report related to
router
2
17:05,223
Restarting the systems
3
18:02,444
Must erase hard disk
now due to compromised data
我想要这个输出：
1
17:02,111
Problem report related to router
2
17:05,223
Restarting the systems
3
18:02,444
Must erase hard disk now due to compromised data
一直在尝试 bash 并找到一种接近的解决方案，但我不知道如何在 Python 上执行此操作。
先感谢您
为此，如果该行后面没有空的新行，或者该行之前应该有与以下 regex 匹配的行，您可以检查每个类似的 2 个条件^\d{2}:\d{2},\d{3}\s$。
因此，为了在每次迭代中访问下一行，您可以从主文件对象创建一个文件对象，其名称为tempusingitertools.tee并在其上应用该next函数。并用于re.match匹配正则表达式。
from itertools import tee
import re
with open('ex.txt') as f,open('new.txt','w') as out:
temp,f=tee(f)
next(temp)
try:
for line in f:
if next(temp) !='\n' or re.match(r'^\d{2}:\d{2},\d{3}\s$',pre):
out.write(line)
pre=line
except :
pass
结果 ：
1
17:02,111
Problem report related to
2
17:05,223
Restarting the systems
3
18:02,444
Must erase hard disk
如果您想将第三行之后的其余行连接到第三行，您可以使用以下正则表达式来查找文件 ( )后面\n\n或结尾的所有块：$
r"(.*?)(?=\n\n|$)"
然后根据日期格式的行拆分块并将部分写入输出文件，但请注意，您需要用空格替换第 3 部分中的新行：
ex.txt：
1
17:02,111
Problem report related to
router
another line
2
17:05,223
Restarting the systems
3
18:02,444
Must erase hard disk
now due to compromised data
line 5
line 6
line 7
演示：
def splitter(s):
for x in re.finditer(r"(.*?)(?=\n\n|$)", s,re.DOTALL):
g=x.group(0)
if g:
yield g
import re
with open('ex.txt') as f,open('new.txt','w') as out:
for block in splitter(f.read()):
first,second,third= re.split(r'(\d{2}:\d{2},\d{3}\n)',block)
out.write(first+second+third.replace('\n',' '))
结果 ：
1
17:02,111
Problem report related to router another line
2
17:05,223
Restarting the systems
3
18:02,444
Must erase hard disk now due to compromised data line 5 line 6 line 7
在这个答案中，该splitter函数返回一个生成器，当您处理大文件并拒绝在内存中存储不可用的行时，该生成器非常有效。
当且仅当文件符合您给定的样本时，这才有效
笔记：
There may be a faster way if regex is used and it might also be simpler但想以合乎逻辑的方式做到这一点
代码：
inp=open("output.txt","r")
inp=inp.read().split("\n")
print inp
tempString=""
output=[]
w=0
for s in inp:
if s:
if any(c.isalpha() for c in s):
tempString=tempString+" "+s
else:
w=0
if tempString:
output.append(tempString.strip())
tempString=""
output.append(s)
else:
if tempString:
output.append(tempString.strip())
tempString=""
output.append(" ")
if tempString:
output.append(tempString.strip())
print "\n".join(output)
out=open("newoutput.txt","w")
out.write("\n".join(output))
out.close()
输入：
1
17:02,111
Problem report related to
2 router
2
17:05,223
Restarting the systems
3
18:02,444
Must erase hard disk
now due to compromised data
4
17:02,111
Problem report related to
router
输出：
1
17:02,111
Problem report related to 2 router
2
17:05,223
Restarting the systems
3
18:02,444
Must erase hard disk now due to compromised data
4
17:02,111
Problem report related to router
x="""1
17:02,111
Problem report related to
router
2
17:05,223
Restarting the systems
3
18:02,444
Must erase hard disk
now due to compromised data
or something"""
def repl(matchobj):
ll=matchobj.group().split("\n")
return "\n".join(ll[:3])+" "+" ".join(ll[3:])
print re.sub(r"\b\d+\n\d+:\d+,\d+\b[\s\S]*?(?=\n{2}|$)",repl,x)
您可以使用re.sub自己的自定义替换功能。