while <FH> {
    my @$record = split $delimiter, $_;
    push(@unsorted, $record);
}
@sorted = sort { $b->[0] cmp $a->[0] } @unsorted;
[download]

If the date format is followed rigidly, with leading 0 for single digit months and days, then a simple alpha sort will work. Since you want reverse order, I'll show how to get that from the sort routine.

my @sorted  = sort {
                    $b->[0] cmp $a->[0]
                   } @data;
[download]

The $b value is on the left to induce reverse order.

If the date format is not so rigidly observed, you can either rewrite it internally to conform to the format, or else do the sort the hard way. That uses a numerical comparison of years, if same then months if same then days:

my @sorted = sort {
                    my @b = split '-', $b->[0];
                    my @a = split '-', $a->[0];
                    $b[0] <=> $a[0] ||
                      $b[1] <=> $a[1] ||
                        $b[2] <=> $a[2];
                   } @data;
[download]

Hope this helps.

After Compline,
Zaxo

Hello! It's very simple to sort date format array.

#! /usr/bin/perl -w
use strict;
use Date::Simple ('date', 'today');

my @dates = ("2010-01-27","2010-01-21","2010-02-13","2010-01-10","2009
+-12-28");

my @ordered = sort{ date($b) <=> date($a)} @dates; #descend order   

print "@ordered\n";
[download]

This is the result: 2010-02-13 2010-01-27 2010-01-21 2010-01-10 2009-12-28

I think what you explained is not, in fact, what you have. You describe a file that has three bits of information in it: one date, one id, and one title. You assign this to an array such that element zero is $date, one is $id, and two is $title.

This is clearly not the case, or there would be no sorting to do! :-) Could you post your code (remember to surround your code with <code> tags) and some sample data?

O.K, sorry! Its 1:22am here and I'm not thinking straight! %P

I havent got the data yet so at the moment i'm just "simulating" 3 lines from the file being in the array:

#!/usr/bin/perl

my @data;

push @data, [ split (/\|/,"2001-07-07|12345|This is a test 1") ];
push @data, [ split (/\|/,"2001-07-08|23456|This is a test 2") ];
push @data, [ split (/\|/,"2001-07-06|34567|This is a test 3") ];

print $data[0][0];
[download]

So as you can see, at the end it prints "2001-07-07" which is the "first row, first column" of the array.

What I want to do is that this array and sort it by date in descending order using the date field.

By the way - what IS the proper term for these sorts of arrays in Perl and how do you refer to the "rows and columns" I always use? *S* I mean, what is it when you know how many "columns" you have but the number of rows (say its being read from a file) is variable?

- Jed