从文件中提取变量名称

Question

我有一个包含大量这样的行的文本文件。

NOTE: Variable Variable_S1 already exists on file D1.D, using Var_S8 instead.  
NOTE: The variable name more_than_eight_letters_m has been truncated to ratio_s.  
NOTE: Variable ratio_s already exists on file D1.D, using Var_S9 instead.  

我正在尝试创建一个包含2列的列表：

Variable_S1 Var_S8   
more_than_eight_letters Var_S9  

有人可以告诉我如何使用sed或python甚至R吗？

Answer 1

我不知道sed或R，但是在Python中：

>>> import re
>>> i = """NOTE: Variable Variable_S1 already exists on file D1.D, using Var_S8 instead.
NOTE: The variable name more_than_eight_letters_m has been truncated to ratio_s.
NOTE: Variable ratio_s already exists on file D1.D, using Var_S9 instead."""
>>> print(re.findall(r'(\w+_\w+)', i))
['Variable_S1', 'Var_S8', 'more_than_eight_letters_m', 'ratio_s', 'ratio_s', 'Var_S9']

这是一个改进版本，它将为您提供每行的变量集：

>>> print([re.findall(r'(\w+_\w+)', line) for line in i.split('\n')])
[['Variable_S1', 'Var_S8'],
 ['more_than_eight_letters_m', 'ratio_s'],
 ['ratio_s', 'Var_S9']]