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Reading file using python and and see if a particular string is there inthe file.

Answer 1

+1 A:

use the in operator to see if there is a match

for line in open("file"):
    if "string" in line :
        ....

ghostdog74 2010-08-09 05:37:12

Answer 2

+2 A:

A build on ghostdog74's answer:

def finder(line):
    '''Takes line number as argument. First line is number 0.'''
    with open('/home/vlad/Desktop/file.txt') as f:
        lines = f.read().split('Summary')[1:]
        searchLine = lines[line]
        if 'meeting' in searchLine.lower() or 'call in number' in searchLine.lower():
            return 'call-in meeting'
        else:
            return 'None Inferred'

I don't quite understand what you meant by line[1] and line[2] so this is the best I could do.

EDIT: Fixed the problem with the \n's. I figure since you're searching for the meeting and call in number you don't need the Summary so I used it to split the lines.

vlad003 2010-08-09 06:22:26

Assuming the OP has stated his/her problem correctly (which is a big assumption!), this won't work: the line numbers will be off, because e.g. `Darlene` will be on a separate line.

katrielalex 2010-08-09 08:50:23

I fixed it. It now splits the lines by the `Summary`; assuming he doesn't need that word in there for searching.

vlad003 2010-08-09 23:15:34

you want to change the `and` to an `or` in the line that begins with `if 'meeting' in searchLine.lower()`

aaronasterling 2010-08-09 23:19:25

thanks very much , sorry for not being clear. Actually i had not notices the /n's inside a line!

LVT 2010-08-11 10:31:10

Answer 3

+1 A:

vlad003 is right: if you have newline characters in the lines; they will be new lines! In this case, I would split on "Summary" instead:

import itertools

def chunks( filePath ):
    "Since you have newline characters in each section,\
    you can't read each line in turn. This function reads\
    lines of the file and splits them into chunks, restarting\
    each time 'Summary' starts a line."
    with open( filePath ) as theFile:
        chunk = [ ]
        for line in theFile:
            if line.startswith( "Summary" ):
                if chunk: yield chunk
                chunk = [ line ]
            else:
                chunk.append( line )
        yield chunk

def nth(iterable, n, default=None):
    "Gets the nth element of an iterator."
    return next(islice(iterable, n, None), default)

def getStatus( chunkNum ):
    "Get the nth chunk of the file, split it by ";", and return the result."
    chunk = nth( chunks, chunkNum, "" ).split( ";" )
    if not chunk[ 0 ]:
        raise SomeError # could not get the right chunk
    if "meeting" in chunk[ 1 ].lower() or "call in number" in chunk[ 1 ].lower():
        return "call-in meeting"
    else:
        return "None Inferred"

Note that this is silly if you plan to read all the chunks of the file, since it opens the file and reads through it once per query. If you plan to do this often, it would be worth parsing it into a better data format (e.g. an array of statuses). This would require one pass through the file, and give you much better lookups.

katrielalex 2010-08-09 08:35:12

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Reading file using python and and see if a particular string is there inthe file.

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