删除段落并将所有内容保存到一行

Question

您好，我不知道如何解释，我有这个问题。目前我有一些文字如下所示：

 picture gallery 
    see also 
    adaptation
    ecology
    extreme environment clothing
    extremophile
    lexen life in extreme environments
    natural environment
    references 
    "extreme environment" microbial life np nd web 16 may 2013
    feminism and gis refers to the use of geographic information system gis for feminist research and also how women influence gis at technological stages feminist gis research is aware of power differences in social and economic realms
     history 

我的问题是我如何才能得到这样的结果，例如：

picture gallery see also adaptation ecology extreme environment clothing extremophile lexen life in extreme environments natural environment references "extreme environment" microbial life np nd web 16 may 2013 feminism and gis refers to the use of geographic information system gis for feminist research and also how women influence gis at technological stages feminist gis research is aware of power differences in social and economic realms

我不确定这叫什么，但到目前为止，我找到的解决方案是删除所有我不需要的空格。

请帮帮我。

谢谢。

Answer 1

如果是文件：

text = file('path/to/your/file.txt').read()
new_text = text.replace('\n', ' ')
print(new_text) # this will have no new lines
with open('output.txt', 'wr') as out:
    out.write(new_text) #this will write it to a file

你也可以使用正则表达式，就像 PJSCopeland 说的：

import re
s = "Example String \n more example string"
replaced = re.sub('\s+', ' ', s)
print replaced

Dilettant 的解决方案简洁、正确，而且比使用正则表达式更快（根据我的衡量），因此我建议将其作为最佳解决方案：

filtered = ' '.join(text.strip().split())

Answer 2

请注意，答案中给出的结果在右边距很有创意，它从输入数据中删除了历史；-) 更新：最新评论表明，数据来自文件，因此更新回答。

将此视为一个不需要的小故障，我建议既不使用正则表达式也不替换。只需像这样一次性完成剥离-拆分-连接转换（假设文本在您调用脚本的文件夹中的文件in.txt 中）：

#! /usr/bin/env python

with open('in.txt', 'rt') as f:
    filtered = ' '.join(f.read().strip().split())

或者 - 如果已经在变量中（并且将期望和比较作为最小测试）：

#! /usr/bin/env python

text = '''picture gallery 
    see also 
    adaptation
    ecology
    extreme environment clothing
    extremophile
    lexen life in extreme environments
    natural environment
    references 
    "extreme environment" microbial life np nd web 16 may 2013
    feminism and gis refers to the use of geographic information system gis for feminist research and also how women influence gis at technological stages feminist gis research is aware of power differences in social and economic realms
     history 
'''

expected = (
    'picture gallery see also adaptation ecology extreme environment'
    ' clothing extremophile lexen life in extreme environments'
    ' natural environment references "extreme environment" microbial'
    ' life np nd web 16 may 2013 feminism and gis refers to the use'
    ' of geographic information system gis for feminist research and'
    ' also how women influence gis at technological stages feminist'
    ' gis research is aware of power differences in social and'
    ' economic realms history')

filtered = ' '.join(text.strip().split())

assert filtered == expected

如果您需要在“单行”结果的末尾换行，您可以改为：

filtered = '%s\n' % (' '.join(text.strip().split()),)

或

filtered = ' '.join(text.strip().split()) + '\n'

在这种情况下，断言或预期变量当然应该同步更改；-)

这应该也是一个逻辑清晰的解决方案。正则表达式通常很诱人，但如果结果对于像这样的简单拆分连接管道是可行的，它们会导致一些运行时复杂性（以及嵌入的另一种语言）。

只需使用上述设置进行测量，并为正则表达式调整一个：

print 'strip-split-join:  ', ['%0.4f' % round(z, 4) for z in timeit.Timer("filtered = ' '.join(text.strip().split())", setup=setup).repeat(7, 1000)]
print 're.sub("\s+", " "):', ['%0.4f' % round(z, 4) for z in timeit.Timer("filtered = replaced = re.sub('\s+', ' ', text)", setup=setup_re).repeat(7, 1000)]

这给出（在我的机器上）：

strip-split-join:   ['0.0043', '0.0045', '0.0047', '0.0046', '0.0043', '0.0040', '0.0045']
re.sub("\s+", " "): ['0.0265', '0.0254', '0.0246', '0.0248', '0.0238', '0.0255', '0.0266']

所以正则表达式解决方案慢了大约。 5 倍。

Answer 3

将/\s+/g（至少一个空白字符的每个实例）替换为" "。 （不幸的是，我不熟悉 Python，所以我不知道方法调用会是什么。）