Grouping with Perl

[de2425]

Hi,

I am having some difficulty thinking of a way to do something that I'm sure is simple. I, however, just cannot get my brain around a way to get Perl to do it. What I have is a file with multiple records. The records contain an ID, name, description, application in that order. There are in some cases several of the same ID listed because one ID may have more than one application. What I want to do is print out the same data to anohter file but I want the ID's listed only once and all of the applications listed in the one line. So basically the data looks like this:

ID, name, description, application
1, XYZ, desc, PDF
1, XYZ, desc, QFZ
2, YGH, desc, LMN

What I'm looking for is:

1, XYZ, desc, PDF,QFZ
2, YGH, desc, LMN

I have been trying to think of a good way to do this for a while and haven't come up with anything. If anyone could help, I'd very much appreciate it.

[numberwhun]

Just so we know how far you have gotten in your attempts to do this, why not post the code you have been working with, here, enclosed in code tags, and we will help you get it working from there.

Regards,

Jeff

[eWish]

I would suggest that you use a hash of hashes.

--Kevin

[de2425]

Just so we know how far you have gotten in your attempts to do this, why not post the code you have been working with, here, enclosed in code tags, and we will help you get it working from there.

Regards,

Jeff

I already got the code going. Thanks for the helpful reply though. The code that ended up working, in case anyone else runs across this type of situation, is:

#!/usr/bin/perl -w
 
open (IN, "input file");
 
while(<IN>){ 
     chomp;
      @t=split(/\t/,$_);
      $AB{$t[0]}=$AB{$t[0]}.",$t[2]";
      }
      print %AB;
close IN;
close OUT;
 
 
open (OUT, ">output file");
open (IN, "input file");
 
while (<IN>){
      chomp;
      @Products=split(/\t/,$_);
 
      if ($Products[0] and exists $AB{$Products[0]}){
      print OUT "$Products[0]\t$Products[2]\t$AB{$Products[0]}\n";
      }
}
 
close IN;
close OUT;