简体   繁体   中英

Python wildcard search in string

Lets say that I have a list

list = ['this','is','just','a','test']

how can I have a user do a wildcard search?

Search Word: 'th_s'

Would return 'this'

Use fnmatch :

import fnmatch
lst = ['this','is','just','a','test']
filtered = fnmatch.filter(lst, 'th?s')

If you want to allow _ as a wildcard, just replace all underscores with '?' (for one character) or * (for multiple characters).

If you want your users to use even more powerful filtering options, consider allowing them to use regular expressions .

Regular expressions are probably the easiest solution to this problem:

import re
regex = re.compile('th.s')
l = ['this', 'is', 'just', 'a', 'test']
matches = [string for string in l if re.match(regex, string)]

You could try the fnmatch module, it's got a shell-like wildcard syntax

or can use regular expressions

import re

Do you mean any specific syntax for wildcards? Usually * stands for "one or many" characters and ? stands for one.

The simplest way probably is to translate a wildcard expression into a regular expression, then use that for filtering the results.

Same idea as Yuushi in using regular expressions, but this uses the findall method within the re library instead of a list comprehension:

import re
regex = re.compile('th.s')
l = ['this', 'is', 'just', 'a', 'test']
matches = re.findall(regex, string)

Why don't you just use the join function? In a regex findall() or group() you will need a string so:

import re
regex = re.compile('th.s')
l = ['this', 'is', 'just', 'a', 'test']
matches = re.findall(regex, ' '.join(l)) #Syntax option 1
matches = regex.findall(' '.join(l)) #Syntax option 2

The join() function allows you to transform a list in a string. The single quote before join is what you will put in the middle of each string on list. When you execute this code part (' '.join(l)) you'll receive this:

'this is just a test'

So you can use the findal() function.

I know i am 7 years late, but i recently create an account because I'm studying and other people could have the same question. I hope this help you and others.


Update After @FélixBrunet comments:

import re
regex = re.compile(r'th.s')
l = ['this', 'is', 'just', 'a', 'test','th','s', 'this is']

matches2=[] #declare a list
for i in range(len(l)): #loop with the iterations = list l lenght. This avoid the first item commented by @Felix
if regex.findall(l[i]) != []: #if the position i is not an empty list do the next line. PS: remember regex.findall() command return a list.
    if l[i]== ''.join(regex.findall(l[i])): # If the string of i position of l list = command findall() i position so it'll allow the program do the next line - this avoid the second item commented by @Félix
        matches2.append(''.join(regex.findall(l[i]))) #adds in the list just the string in the matches2 list

print(matches2)

Easy method is try os.system :

import os
text = 'this is text'
os.system("echo %s | grep 't*'" % text)

The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM