Python 2.7 拆分和 .col 连接

Question

我使用的是python 2.7版本。

我正在尝试使用 python 提取数组列名称。

数组列如下:

`col` array<struct< columnname:string,columnname1:int,columnname2:decimal(10,0),
columnname3:decimal(9,2)>>

到目前为止我尝试过的:

import re
str=input("enter any string:")
fields=str.split(",")
for x in fields:
  name=x.split(":")
  seminame=name[0]+','
  firstname=seminame.find('`')
  lastname=seminame.rfind('`')
  fullname=seminame[(firstname+1):lastname]
  replacename1=fullname.replace(')', '')
  replacename2=fullname.replace('2', '')
  replacename3=fullname.replace('9', '')
  replacename4=fullname.replace('10', '')
  replacename5=fullname.replace('0', '')
  finalname='.'+replacename5
  print(finalname)

<小时/>

Input:
'`col` array<struct< columnname:string,columnname1:int,columnname2:decimal(10,0),
columnname3:decimal(9,2)>>'

我想要输出为

Actual output
.col,
.columnname1,
.columnname2,
.),

Expected output
col.columnname,
col.columnname1,
col.columnname2,
col.columnname3

Answer 1

为什么不使用 re 来做同样的事情？

import re
str = "'`col` array<struct< columnname:string,columnname1:int,columnname2:decimal(10,0),columnname3:decimal(9,2)>>'"
word = re.findall("`\w+`",str,) # match for columns 
word = " ".join(word)
word = re.sub(r'\W+', '', word) # strip `` 
columnnames = re.findall(r"(\w+):",str) # find all words before `:`
for c in columnnames:
  c = re.sub(r'\W+', '', c) # to remove `:`
  print  "%s.%s," %( word,c)

输出:

col.columnname,
col.columnname1,
col.columnname2,
col.columnname3,

要从文件中读取，您可以使用open(filename,mode)方法

import re
with open("test.txt","r") as h:
 str = h.read()
 word = re.findall(r"`\w+`",str,)
 word = " ".join(word)
 word = re.sub(r'\W+', '', word)
 columnnames = re.findall(r"(\w+):",str)
 for c in columnnames:
    c = re.sub(r'\W+', '', c)
    print  "%s.%s," %( word,c)

写入文件:

import re
with open("test.txt","r") as h:
with open("output.dat","a") as w:
str = h.read()
word = re.findall(r"`\w+`",str,)
word = " ".join(word)
word = re.sub(r'\W+', '', word)
columnnames = re.findall(r"(\w+):",str)
for c in columnnames:
    c = re.sub(r'\W+', '', c)
    data =  "%s.%s," %( word,c)
    w.write(data+"\n")
w.close()
h.close()