pythonreescape

A. 我在学习python编程，请问下怎么实现模糊查询

importre
f=open('user.txt','r')
text=f.read()
f.close()
tofind=raw_input("pleaseinputyowanttofind:")
tofind=re.escape(tofind)
result=re.findall(".*"+tofind+".*",text)
forlineinresult:printline

B. 请问python如何按照属性分类

step1:解析行,得到行中的parid

step2:建立以parid为key的字典采集行

step3:按字典的key输出文件

#!/usr/bin/python
#coding:utf-8
#
#date:Dec.,2013

importre

patt=re.compile(r".*[parid=(?P<parid>[^]]*)].*")

deffileparser(filename):
buff=[]
withopen(filename)ashandle:
forlninhandle:
ifln.startswith('[fn]')ornotbuff:
buff.append(ln)
else:
buff[-1]+=ln
returnbuff


collector={}
forlninfileparser('fn_test.txt'):
collector.setdefault(patt.match(ln).groupdict().get("parid"),[]).append(ln)

#storagetotextfile
forparid,lnsincollector.items():
withopen("%s.txt"%parid,'wt')ashandle:
handle.writelines(lns)

C. 这个python程序运行出错怎么改

你要检查web模块是否包含run这个内容。可以用dir命令， 如
>>> dir(re)
['DEBUG', 'DOTALL', 'I', 'IGNORECASE', 'L', 'LOCALE', 'M', 'MULTILINE', 'S', 'Scanner', 'T', 'TEMPLATE', 'U', 'UNICODE', 'VERBOSE', 'X', '_MAXCACHE', '__all__', '__builtins__', '__doc__', '__file__', '__name__', '__package__', '__version__', '_alphanum', '_cache', '_cache_repl', '_compile', '_compile_repl', '_expand', '_pattern_type', '_pickle', '_subx', 'compile', '_reg', 'error', 'escape', 'findall', 'finditer', 'match', 'purge', 'search', 'split', 'sre_compile', 'sre_parse', 'sub', 'subn', 'sys', 'template']

D. 求教，python如何输出特定字符间的数据

a=open('a').read()
b=open('b').read()
importre
ids=re.findall('(?!S)%%w+',a)
foridinids:
id=re.escape(id)
match=re.search(id+"(?!w).*?(?=%%|)",b,re.S)
ifmatch:
print(match.group(0))

以上是从a文件读取ID,然后输出b文件相应ID下内容的代码

只葽a文件和b文件中ID都是唯一的就可以

E. Python如何将字符串中的符号都换为空格

import re
import string

text=re.sub(re.escape(string.punctuation)," ",text)

F. python，把中序表达式转换成前序表达式的代码，求大神相助。

我有一个转后序的代码你可以看看
def Infix2PostfixExp(self,inputStr,parDict):
print ("Now the inputStr is "+inputStr)
form = re.escape(r"*<>=/+-()&|!?:")
form1 = re.escape(r"<=")
form2 = re.escape(r">=")
form3 = re.escape(r"&&")
form4 = re.escape(r"||")
#print (form)
tmpList = re.split(r"(" + form1+"|"+form2+ "|"+form3 +"|"+form4+ "|["+form+"])",inputStr)
print ("Next will print the split result")
print (tmpList)
print ("Next is the parDict value")
print (parDict)
resultList =[]
opList = []
widthInfo =0

for eachItem in tmpList:
each =eachItem.strip()
if each == "" or each == " ":
continue
elif each == "&&" :
each ="&"
elif each == "||" :
each ="|"
elif each in parDict:
print ("the key is "+each)
(each,widthInfo) = parDict[each]
#widthInfo = parDict[each][1]
print ("the value comes from parDict " +str(each))

if "{" in each and "}" in each:
helpList = re.split("[\{\,\}]",each)
resultValue = 0
resultWidthInfo = 0
print (helpList)
for eachOne in helpList:
(tmp,widthInfo) = self.CalValue(eachOne,parDict)
if tmp !="":
resultValue = resultValue<<widthInfo +int(tmp)
resultWidthInfo += widthInfo
else:
print ("the format is not reconige!")
print (eachOne)
print (each)
sys.exit(1)
resultList.append(resultValue)
print ("The result value is " +str(resultValue))
continue

(tmp,widthInfo) = self.CalValue(each,parDict)
if tmp !="":
resultList.append(tmp)
continue

#print ("next will process " +str(each))
if self.isNumber(each):
#print ("we will add below to resultList " +each)
resultList.append(each)
elif each =="(":
opList.append(each)
elif each ==")":
tmp = opList.pop()
while tmp != "(":
resultList.append(tmp)
tmp = opList.pop()
elif each in "+-":
if len(opList) !=0:
(opList,resultList) = self.ExpStackOP(opList,resultList,each)
else:
opList.append(each)
elif each in "*/":
if len(opList) !=0:
(opList,resultList) = self.ExpStackOP(opList,resultList,each)
else:
opList.append(each)
elif each in "&|^":
if len(opList) !=0:
if opList[-1] == "(":
opList.append(each)
else:
tmp = opList.pop()
resultList.append(tmp)
opList.append(each)
else:
opList.append(each)
elif each =="?":
if len(opList) !=0:
tmp = opList.pop()
resultList.append(tmp)
else:
print ("The length for opList is wrong")
print (opList)
print (inputList)
print (resultList)
sys.exit(1)
opList.append(each)
else:
opList.append(each)
print (opList)
print (resultList)

if len(opList)!=0:
for index in range(0,len(opList)):
tmp = opList.pop()
resultList.append(tmp)

print (resultList)

G. python3怎么导入re模块

Python除了 str 对象自带的一些方法外，re文字处理能力也很强大。

正则表达式元字符说明
[python正则表达式]
导入和查看正则表达式模块

import re
查看正则表达式模块方法
dir(re)
[‘DEBUG’, ‘DOTALL’, ‘I’, ‘IGNORECASE’, ‘L’, ‘LOCALE’, ‘M’, ‘MULTILINE’, ‘S’, ‘Scanner’, ‘T’,’TEMPLATE’, ‘U’, ‘UNICODE’, ‘VERBOSE’, ‘X’, ‘_MAXCACHE’, ‘all‘, ‘builtins‘, ‘doc‘,’file‘, ‘name‘, ‘package‘, ‘version‘, ‘_alphanum’, ‘_cache’, ‘_cache_repl’,’_compile’, ‘_compile_repl’, ‘_expand’, ‘_pattern_type’, ‘_pickle’, ‘_subx’, ‘compile’,’_reg’, ‘error’, ‘escape’, ‘findall’, ‘finditer’, ‘match’, ‘purge’, ‘search’, ‘split’,’sre_compile’, ‘sre_parse’, ‘sub’, ‘subn’, ‘sys’, ‘template’]
提示：
1. 当我们不会用模块方法的时候用help
2. py2中pattern中的字符串要和string的编码一致，不然会找不到，这个经常出现。

H. python中的re模块是自带的吗

使用python的re模块，尽管不能满足所有复杂的匹配情况，但足够在绝大多数情况下能够有效地实现对复杂字符串的分析并提取出相关信息。
python 会将正则表达式转化为字节码，利用 C 语言的匹配引擎进行深度优先的匹配。

I. python基础教程 10-11例子如何执行

2020年最新Python零基础教程（高清视频）网络网盘

链接:

若资源有问题欢迎追问~

J. 如何用python删除txt中指定段落的内容 比如txt内容是 <a> x <b> <a> y <b> 我

importre
text=open(r"test.txt").read()
rep=re.escape(r"y")
text=re.sub("<a>
"+rep+"
<b>","<a>
<b>",text)
f=open(r"test.txt","w")
f.write(text)
f.close()