Regex用于删除直到特定字符的新行

Question

我在一个文件中有一系列字符串，格式如下：

>HEADER_Text1
Information here, yada yada yada
Some more information here, yada yada yada
Even some more information here, yada yada yada
>HEADER_Text2
Information here, yada yada yada
Some more information here, yada yada yada
Even some more information here, yada yada yada
>HEADER_Text3
Information here, yada yada yada
Some more information here, yada yada yada
Even some more information here, yada yada yada

我正在尝试寻找一个正则表达式模式，它将删除下一个>字符之间的>字符下面的换行符。因此，最终结果将如下所示：

>HEADER_Text1
Information here, yada yada yada Some more information here, yada yada yada Even some more information here, yada yada yada
>HEADER_Text2
Information here, yada yada yada Some more information here, yada yada yada Even some more information here, yada yada yada
>HEADER_Text3
Information here, yada yada yada Some more information here, yada yada yada Even some more information here, yada yada yada

有人知道我是如何想出一个正则表达式模式来做这件事的吗？

附注:这种格式在计算科学中是一种常见的FASTA格式。

谢谢!

Answer 1

正如注释中所指出的，最好的选择是使用现有的FASTA解析器。为什么不行？

下面是我如何根据前导的大于号来连接行：

def joinup(f):
    buf = []
    for line in f:
        if line.startswith('>'):
            if buf:
                yield " ".join(buf)
            yield line.rstrip()
            buf = []
        else:
            buf.append(line.rstrip())
    yield " ".join(buf)

for joined_line in joinup(open("...")):
    # blah blah...

Answer 2

假设>总是应该是新行上的第一个字符

"\n(^>)“，带”\1“

Answer 3

您不必使用regex：

[ x.startswith('>') and x or x.replace('\n','') for x in f.readlines()]    

应该行得通。

In [43]: f=open('test.txt')

In [44]: contents=[ x.startswith('>') and x or x.replace('\n','') for x in f.readlines()]                                                                                   

In [45]: contents
Out[45]: 
['>HEADER_Text1\n',
 'Information here, yada yada yada',
 'Some more information here, yada yada yada',
 'Even some more information here, yada yada yada',
 '>HEADER_Text2\n',
 'Information here, yada yada yada',
 'Some more information here, yada yada yada',
 'Even some more information here, yada yada yada',
 '>HEADER_Text3\n',
 'Information here, yada yada yada',
 'Some more information here, yada yada yada',
 'Even some more information here, yada yada yada']