Quick Sort Question

thricewise has asked for the wisdom of the Perl Monks concerning the following question:

Hello all. I am not new to unix, but very new to perl. I have a nifty little script set up that finds people with an ID of 100,1000,10000 you get the point, but I am now trying to sort it alphabetically by last name and I am running into all kinds of snags, here is the scrpt any help would be appreciated

#!/usr/bin/perl -w
use strict;

my ($ID, $DP, $LN, $FN, $NM);

open(EMPLOYEES,"<employees") || die "Cannot Open";

while(<EMPLOYEES>) {
   if(/(.*):(1.*):(.*):(.*):(.*)/) {
      #Supposed to parse $_
      $ID = $1;
      $DP = $2;
      $LN = $3;
      $FN = $4;
      $NM = $5;
      print $ID; #
      print $DP; #
      print $LN; # So I can see if a value is there
      print $FN; #
      print $NM; #
chomp;
    (my @f = split(/:/)) == 5 or next;
    print join("\t", @f[2, 3, 0, 4]), "\n";
   }
}
close(EMPLOYEES)
[download]

Comment on Quick Sort Question Download Code

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Re: Quick Sort Question by zwon (Abbot) on Dec 09, 2009 at 20:23 UTC
Something like this should work (not tested!): `use strict; use warnings; open my $fh, "<", "employees" or die "Cannot Open: $!"; my @employees; while (<$fh>) { chomp; if (/(.):(1.):(.):(.):(.)/) { push @employees, [ $1, $2, $3, $4, $5 ]; } } close $fh; @employees = sort { $a->[2] cmp $b->[2] } @employees; for (@employees) { print join( "\t", @$_[ 2, 3, 0, 4 ] ), "\n"; }` [download] Update:* bug fixed	[reply] [d/l]
Re^2: Quick Sort Question by thricewise (Initiate) on Dec 09, 2009 at 20:48 UTC
I am getting an uninitialized value in join error if I try it the way you have it.	[reply]
Re^3: Quick Sort Question by almut (Canon) on Dec 09, 2009 at 21:01 UTC
Try `@$_[ 2, 3, 0, 4 ]` (the for loop aliases individual arrayrefs to the default variable `$_`, which you need to dereference and slice)	[reply] [d/l] [select]
Re^4: Quick Sort Question by thricewise (Initiate) on Dec 09, 2009 at 21:06 UTC
Re^3: Quick Sort Question by zwon (Abbot) on Dec 09, 2009 at 21:03 UTC
I warned that it's not tested, and the reason is that you didn't provide us with test input ;) I fixed the problem, that should be `@$_[...]` instead of `@_[...]`	[reply] [d/l] [select]
Re: Quick Sort Question by baxy77bax (Deacon) on Dec 09, 2009 at 20:30 UTC
well if you can afford to store the data in memora this could work for you `use strict; my @array; while(<DATA>){ chomp; my @arr = split(',',$_); push (@array,\@arr); } @array = sort{$a->[1] cmp $b->[1]}@array; foreach (@array){ print "@$_ \n"; } __DATA__ miki,maus,kiki sis,miki,misi nick,pick,flick amico,aco,taco` [download]	[reply] [d/l]