Searching through more than one file.

[Albert-Jan Roskam]

-----------------------------
On Sun, Dec 28, 2014 8:12 PM CET Dave Angel wrote:

>On 12/28/2014 12:27 PM, Seymore4Head wrote:
>> I need to search through a directory of text files for a string.
>> Here is a short program I made in the past to search through a single
>> text file for a line of text.
>> 
>> How can I modify the code to search through a directory of files that
>> have different filenames, but the same extension?
>> 
>
>You have two other replies to your specific question, glob and os.listdir.  I would also mention the module fileinput:
>
>https://docs.python.org/2/library/fileinput.html


Ah, I was just about to say that. I found out about this gem after reading Dough Helmann's book. Here are some usage examples: http://pymotw.com/2/fileinput/


>import fileinput
>from glob import glob
>
>fnames = glob('*.txt')
>for line in fileinput.input(fnames):
>    pass # do whatever
>
>If you're not on Windows, I'd mention that the shell will expand the wildcards for you, so you could get the filenames from argv even simpler.  See first example on the above web page.
>
>
>I'm more concerned that you think the following code you supplied does a search for a string.  It does something entirely different, involving making a crude dictionary.  But it could be reduced to just a few lines, and probably take much less memory, if this is really the code you're working on.
>
>> fname = raw_input("Enter file name: ")  #"*.txt"
>> fh = open(fname)
>> lst = list()
>> biglst=[]
>> for line in fh:
>>      line=line.rstrip()
>>      line=line.split()
>>      biglst+=line
>> final=[]
>> for out in biglst:
>>      if out not in final:
>>          final.append(out)
>> final.sort()
>> print (final)
>> 
>
>Something like the following:
>
>import fileinput
>from glob import glob
>
>res = set()
>fnames = glob('*.txt')
>for line in fileinput.input(fnames):
>    res.update(line.rstrip().split())
>print sorted(res)
>
>
>
>
>-- DaveA
>-- https://mail.python.org/mailman/listinfo/python-list