Question

第一次發佈和一點菜鳥，所以如果任何禮儀或格式問題，然後讓我知道。

我試圖在文件（圖像下面）上使用grep函數來檢查文件中是否存在單詞。當我查看文件時，這個詞絕對存在。它被空間包圍，並且是一行中的最後一個詞。

由於某種原因，grep無法找到該單詞，程序返回0.爲什麼？

謝謝！

import os 
import re 

word = "aliows" 
folder = '/Users/jordanfreedman/Thinkful/Projects/Spam_Filter/enron1/spam/' 
email = '4201.2005-04-05.GP.spam.txt' 

number = int(os.popen("grep -w -i -l " + word + " " + folder + email + " | wc -l").read()) 
print number 

Answer 1

您需要發佈該文件的片段，以便我們可以測試grep語句。此外，沒有理由掏出：

import re 

word = "aliows" 
folder = '/Users/jordanfreedman/Thinkful/Projects/Spam_Filter/enron1/spam/' 
email = '4201.2005-04-05.GP.spam.txt' 

file = folder + email 
fh = open(file, 'r') 

contents = re.findall(word, fh.read()) 

print(len(contents)) 

Answer 2

你可以找出是否存在使用退出狀態匹配：

import os 
from subprocess import STDOUT, call 

path = os.path.join(folder, email) 
with open(os.devnull, 'wb', 0) as devnull: 
    rc = call(['grep', '-w', '-l', '-i', '-F', word, path], 
      stdout=devnull, stderr=STDOUT) 
if rc == 0: 
    print('found') 
elif rc == 1: 
    print('not found') 
else: 
    print('error') 

或者as @stevieb mentioned，你能找到的單詞是否是在給定的在純Python中的文件：

import re 
from contextlib import closing 
from mmap import ACCESS_READ, mmap 

with open(path) as f, closing(mmap(f.fileno(), 0, access=ACCESS_READ)) as m: 
    if re.search(br"(?i)\b%s\b" % re.escape(word), m): 
     print('found')