Perl

Perl RSS

Compare two Text File

•

Join Date: May 2007

Posts: 2

Reputation: srvinu is an unknown quantity at this point

Solved Threads: 0

srvinu

Offline

Newbie Poster

Compare two Text File

May 23rd, 2007

Hi,
I have one perl script for comparing two text file entries. But its not working according to my expectation. Its comparing line by line, not like comparing one entry to the complete file. I like the script to be compare all the entries irrespective of line by line comparison.

$f1 = 'E:\upload\new\2.txt';
open FILE1, "$f1" or die "Could not open file \n";
$f2= 'E:\upload\new\a.txt';
open FILE2, "$f2" or die "Could not open file \n";

$outfile = 'E:\upload\new\1.txt';

my @outlines;

foreach (<FILE1>) {
$y = 0;
$outer_text = $_;

seek(FILE2,0,0);

foreach (<FILE2>) {
$inner_text = $_;

if($outer_text eq $inner_text) {
$y = 1;
print "$outer_text, Match found \n";
last;
}
}

if($y != 1) {
print "$outer_text,No Match Found \n";
push(@outlines, $outer_text);
}
}

open (OUTFILE, ">$outfile") or die "Cannot open $outfile for writing \n";
print OUTFILE @outlines;
close OUTFILE;

close FILE1;
close FILE2;

Can anybody please help me to enhace the script.

Thanks in advance
Vinod

Last edited by srvinu; May 23rd, 2007 at 6:11 am.

•

Join Date: Dec 2005

Posts: 5,850

Reputation: Salem has a reputation beyond repute

Solved Threads: 749

Salem

Offline

Void main'ers are DOOMed

Re: Compare two Text File

May 23rd, 2007

Please use [code][/code] tags when posting code.
http://www.daniweb.com/techtalkforum...ment112-3.html

If you're trying to determine which lines are common to both files, then perhaps an easier approach would be to look at the Unix ulilities
- sort
- diff
- comm

•

Join Date: Mar 2006

Posts: 898

Reputation: KevinADC has a spectacular aura about

Solved Threads: 67

KevinADC

Offline

Practically a Posting Shark

Re: Compare two Text File

May 23rd, 2007

Use a hash to compare the lines.

 Help with Code Tags 
 Perl Syntax (Toggle Plain Text) 
use strict;
use warnings;
 
my $f1 = 'E:\upload\new\2.txt';
my $f2 = 'E:\upload\new\a.txt';
my $outfile = 'E:\upload\new\1.txt';
my %results = ();
 
open FILE1, "$f1" or die "Could not open file: $! \n";
while(my $line = <FILE1>){
   $results{$line}=1;
}
close(FILE1);
 
open FILE2, "$f2" or die "Could not open file: $! \n";
while(my $line =<FILE2>) {
   $results{$line}++;
}
close(FILE2);
 
 
open (OUTFILE, ">$outfile") or die "Cannot open $outfile for writing \n";
foreach my $line (keys %results) {
   print OUTFILE $line if $results{$line} == 1;
}
close OUTFILE;
use strict;
use warnings;

my $f1 = 'E:\upload\new\2.txt';
my $f2 = 'E:\upload\new\a.txt';
my $outfile = 'E:\upload\new\1.txt';
my %results = ();

open FILE1, "$f1" or die "Could not open file: $! \n";
while(my $line = <FILE1>){
   $results{$line}=1;
}
close(FILE1);

open FILE2, "$f2" or die "Could not open file: $! \n";
while(my $line =<FILE2>) {
   $results{$line}++;
}
close(FILE2);


open (OUTFILE, ">$outfile") or die "Cannot open $outfile for writing \n";
foreach my $line (keys %results) {
   print OUTFILE $line if $results{$line} == 1;
}
close OUTFILE;

There are also some perl modules that will compare files, or you can use the operating system commands Salem mentions.

•

Join Date: May 2007

Posts: 2

Reputation: srvinu is an unknown quantity at this point

Solved Threads: 0

srvinu

Offline

Newbie Poster

Re: Compare two Text File

May 24th, 2007

•

Originally Posted by Salem

Please use tags when posting code.
http://www.daniweb.com/techtalkforum...ment112-3.html

If you're trying to determine which lines are common to both files, then perhaps an easier approach would be to look at the Unix ulilities
- sort
- diff
- comm

Thanks Salem, for the information. But I m try to do the the comparison not like line by line...

Example.

File A------------------------File B
uid=1------------------------uid=4
uid=2------------------------uid=3
uid=3------------------------uid=2
uid=4------------------------uid=1
uid=5
uid=6
In this case you can see file A is having all the values of file be, if we comapare file A with file B its showing "No Match". But i want the comparison like File A should match File B, as the value exist in File B. It will be good if you advice for the same.

Thanks again
Vinod

•

Join Date: Mar 2006

Posts: 898

Reputation: KevinADC has a spectacular aura about

Solved Threads: 67

KevinADC

Offline

Practically a Posting Shark

Re: Compare two Text File

May 24th, 2007

Didn't like my suggestion?

•

Join Date: Dec 2005

Posts: 5,850

Reputation: Salem has a reputation beyond repute

Solved Threads: 749

Salem

Offline

Void main'ers are DOOMed

Re: Compare two Text File

May 24th, 2007

I think you should be able to pick your answer out of some combination of these commands.

 Help with Code Tags 
 Perl Syntax (Toggle Plain Text) 
$ head xF*
==> xF1.txt <==
uid=1
uid=2
uid=3
uid=4
uid=5
uid=6
 
==> xF2.txt <==
uid=4
uid=3
uid=2
uid=1
$ sort -o tmp1.txt xF1.txt && sort -o tmp2.txt xF2.txt
$ diff tmp1.txt tmp2.txt
5,6d4
< uid=5
< uid=6
$ comm -12 tmp1.txt tmp2.txt  # lines common to both files
uid=1
uid=2
uid=3
uid=4
$ comm -13 tmp1.txt tmp2.txt  # lines only in file 2 (none)
$ comm -23 tmp1.txt tmp2.txt  # lines only in file 1
uid=5
uid=6
$ comm -3 tmp1.txt tmp2.txt   # lines unique in file 1 OR file 2 (not  in both)
uid=5
uid=6
$ head xF*
==> xF1.txt <==
uid=1
uid=2
uid=3
uid=4
uid=5
uid=6

==> xF2.txt <==
uid=4
uid=3
uid=2
uid=1
$ sort -o tmp1.txt xF1.txt && sort -o tmp2.txt xF2.txt
$ diff tmp1.txt tmp2.txt
5,6d4
< uid=5
< uid=6
$ comm -12 tmp1.txt tmp2.txt  # lines common to both files
uid=1
uid=2
uid=3
uid=4
$ comm -13 tmp1.txt tmp2.txt  # lines only in file 2 (none)
$ comm -23 tmp1.txt tmp2.txt  # lines only in file 1
uid=5
uid=6
$ comm -3 tmp1.txt tmp2.txt   # lines unique in file 1 OR file 2 (not  in both)
uid=5
uid=6