Python - Find line number from text file [closed]

Answer 1

Something like this:

import re
import os # You can go without is if you have other means to get your filepath

i = 1
matches = []
target = raw_input("Please type string to match\n")
with open(os.getenv("SOME_PATH") + "/myfile.txt") as fic: # open("myfile.txt") if in your current directory
     for line in fic:
         if re.search(target, line):
             print "Found at line {}".format(i)
             matches.append(i)
         i = i +1
if not len(matches):
    raise Exception, "target not found"

By doing this, you can input a regular expression and it should work (i.e. if you input "p.zza" or "^p.*", it will work.). The list matches will contain all indices of lines that match the input pattern.