Get Line Number of certain phrase in file Python

Question

I need to get the line number of a phrase in a text file  The phrase could be   the dog barked   I need to open the file  search it for that phrase and print the line number   I m using Python 2 6 on Windows XP    This Is What I Have   o   open  C  file txt   j   o read   if  the dog barked  in j       print  Found It  else       print  Couldn t Find It    This is not homework  it is part of a project I am working on  I don t even have a clue how to get the line number

User · Answer

for n line in enumerate open  file         if  pattern  in line  print n 1

User · Answer

suzanshakya  I m actually modifying your code  I think this will simplify the code  but make sure before running the code the file must be in the same directory of the console otherwise you ll get error   lookup  The String You re Searching  file name   open  file txt   for num  line in enumerate file name 1           if lookup in line              print num

User · Answer

You can use list comprehension  content   open  quot path to file txt quot   readlines    lookup    the dog barked   lines    line num for line num  line content in enumerate content  if lookup in line content   print lines

User · Answer

f   open  some file txt   r   line num   0 search phrase    the dog barked  for line in f readlines        line num    1     if line find search phrase   gt   0          print line num   EDIT 1 5 years later  after seeing it get another upvote   I m leaving this as is  but if I was writing today would write something closer to Ash suzanshakya s solution     def line num for phrase in file phrase  the dog barked   filename  file txt       with open filename  r   as f          for  i  line  in enumerate f               if phrase in line                  return i     return -1    Using with to open files is the pythonic idiom -- it ensures the file will be properly closed when the block using the file ends    Iterating through a file using for line in f is much better than for line in f readlines      The former is pythonic  e g   would work if f is any generic iterable  not necessarily a file object that implements readlines   and more efficient f readlines   creates an list with the entire file in memory and then iterates through it      if search phrase in line is more pythonic than if line find search phrase   gt   0  as it doesn t require line to implement find  reads more easily to see what s intended  and isn t easily screwed up  e g   if line find search phrase  and if line find search phrase   gt  0 both will not work for all cases as find returns the index of the first match or -1     Its simpler cleaner to wrap an iterated item in enumerate like for i  line in enumerate f  than to initialize line num   0 before the loop and then manually increment in the loop    Though arguably  this is more difficult to read for people unfamiliar with enumerate       See code like pythonista

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Here s what I ve found to work   f rd   open path   r   file lines   f rd readlines   f rd close    matches    line for line in file lines if  chars of Interest  in line  index   file lines index matches 0

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lookup    the dog barked   with open filename  as myFile      for num  line in enumerate myFile  1           if lookup in line              print  found at line    num

User · Answer

listStr   open  file name   mode    if  search element  in listStr      print listStr index  search element      This will gives you the line number

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def get line number phrase  file name       with open file name  as f          for i  line in enumerate f  1               if phrase in line                  return i

User · Answer

Open your file  and then do something like     for line in f      nlines    1     if  line find phrase   gt   0           print  Its here    nlines   There are numerous ways of reading lines from files in Python  but the for line in f technique is more efficient than most

[python] Get Line Number of certain phrase in file Python

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