正在解析结构文件 Python

Question

我想了解在 Python 中使用构造 Case When 的特殊性。我有以下类型的文本文件：

Head 1
a 10
a 14
a 15
Head 4
a 32
a 55
a 79
Head 53
a 22
a 33
Head 33
a 11
a 66
Head 32
a 88
a 89
a 88
End

我想将此文件解析并构建到下一个平面：

Head 1, a 10
Head 1, a 14
Head 1, a 15
Head 4, a 32
Head 4, a 55
Head 4, a 79
Head 53, a 22
Head 53, a 33
Head 33, a 11
Head 33, a 66
Head 32, a 88
Head 32, a 89
Head 32, a 88

刚开始学习的第一件事Python这是没有的情况下。

我尝试的方式：

array = []
with open('C:/file/1.txt') as f:
 for line in f:
  if line[0:4] == 'Head':
   Header = line
   print(Header)
  elif line[0:1] == 'a':
   Subheader = line
   print(Subheader)
  else:
   continue

是否可以使用这种方法将数据分解为所需的格式？谢谢

Answer 1

您可以使用 itertools.groupby:

import itertools
data = [i.strip('\n').split() for i in open('filename.txt')][:-1]
s = [list(b) for _, b in itertools.groupby(data, key=lambda x:x[0] == 'Head')]
new_s = [s[i]+s[i+1] for i in range(0, len(s), 2)]
final_s = [[i[0]+b for b in i[1:]] for i in new_s]
with open('filename1.txt', 'a') as f:
  for row in final_s:
    for i in row:
      f.write('{} {}, {} {}\n'.format(*i))

输出：

Head 1, a 10
Head 1, a 14
Head 1, a 15
Head 4, a 32
Head 4, a 55
Head 4, a 79
Head 53, a 22
Head 53, a 33
Head 33, a 11
Head 33, a 66
Head 32, a 88
Head 32, a 89
Head 32, a 88

Answer 2

假设您的文件名为 filename.txt:

>>> with open('filename.txt', 'r') as f:
...     current_head = None
...     result = []
...     for line in f:
...         if line.startswith('End'):
...             break
...         elif line.startswith('Head'):
...             current_head = line.rstrip()
...         else:
...             result.append('{}, {}'.format(current_head, line.rstrip()))
... 
>>> for line in result:
...     print(line)
... 
Head 1, a 10
Head 1, a 14
Head 1, a 15
Head 4, a 32
Head 4, a 55
Head 4, a 79
Head 53, a 22
Head 53, a 33
Head 33, a 11
Head 33, a 66
Head 32, a 88
Head 32, a 89
Head 32, a 88

正在解析结构文件 Python

Parsing srtructure file Python

python

parsing

if-statement

case-when