Home Backend Development Python Tutorial Python uses regular expressions to implement sample code for searching words

Python uses regular expressions to implement sample code for searching words

Sep 25, 2017 am 11:26 AM
python search expression

Regular expression itself is a small, highly specialized programming language. The following article mainly introduces you to the relevant information about using regular expressions to search for words in Python. The article gives detailed example code. , friends in need can refer to it, let’s take a look below.

Preface

In python, through the embedded re module, programmers can directly call it to achieve regular matching. Regular expression patterns are compiled into a series of bytecodes and then executed by a matching engine written in C.

For example, the following example is used to find a word from a paragraph of text, as follows:

Example code


import re 
 
pattern = 'this' 
text = 'http://blog.csdn.net/caimouse is great, this is great way!' 
 
match = re.search(pattern, text) 
 
s = match.start() 
e = match.end() 
 
print('Found "{}"\nin "{}"\nfrom {} to {} ("{}")'.format( 
 match.re.pattern, match.string, s, e, text[s:e]))

The result output is as follows:


##

Found "this"
in "http://blog.csdn.net/caimouse is great, this is great way!"
from 40 to 44 ("this")
Use

start( here ) indicates the starting position of matching, and end() indicates the ending position.

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