Re: How to Order an Array's Elements to Match Another Array's Element Order

[ozboomer]

Ok... Something to contemplate...

Firstly, some example program code:-

use warnings;
use strict;

use Data::Dumper;
use Tie::IxHash;

my %hash;

tie %hash, "Tie::IxHash";

%hash = ();

while (my $buf = <DATA>) {
   chomp($buf);
   my ($vitem, $project_info) = split(/,/, $buf);
   my ($project_name, $segment_info) = split(/\|/, my $project_info);
   my (@segments) = split(/;/, $segment_info);
   
   push(@{$hash{$project_name}{$vitem}}, @segments);
}

print Dumper(%hash);

exit(0);

# -----------

__DATA__
J_071117,BM:3|12.0-25.2;32.9-88.0
J_070424,BM:3|625-920;1017.905-1178
J_021212,BB:1|123-166;409-455
070526,SWT:1|53.160-59.320;77.720-86.120;370.800-416.800
070609,SWT:1|713.760-1159.200
070616a,SWT:1|0.0-652.0
070616b,SWT:1|401.40-461.800;483.160-490.640;503.400-595.200;602.440-6
+95.400;699.200-882.400
J_071019a,SWT:1|372.925-910.385;927.620-1038.830
J_071019b,SWT:1|268.15-808.330
J_071025,SWT:1|936.215-1659.635
071123_F,SWT:1|45.4550-81.665

...and the output it produces:-

$VAR1 = 'BM:3';
$VAR2 = {
          'J_070424' => [
                          '625-920',
                          '1017.905-1178'
                        ],
          'J_071117' => [
                          '12.0-25.2',
                          '32.9-88.0'
                        ]
        };
$VAR3 = 'BB:1';
$VAR4 = {
          'J_021212' => [
                          '123-166',
                          '409-455'
                        ]
        };
$VAR5 = 'SWT:1';
$VAR6 = {
          '070526' => [
                        '53.160-59.320',
                        '77.720-86.120',
                        '370.800-416.800'
                      ],
          '071123_F' => [
                          '45.4550-81.665'
                        ],
          'J_071019a' => [
                           '372.925-910.385',
                           '927.620-1038.830'
                         ],
          'J_071025' => [
                          '936.215-1659.635'
                        ],
          '070609' => [
                        '713.760-1159.200'
                      ],
          '070616b' => [
                         '401.40-461.800',
                         '483.160-490.640',
                         '503.400-595.200',
                         '602.440-695.400',
                         '699.200-882.400'
                       ],
          '070616a' => [
                         '0.0-652.0'
                       ],
          'J_071019b' => [
                           '268.15-808.330'
                         ]
        };

As (I) expected/understood, the 'first-level' key is maintained in insertion order. However, subsequent (hash) key items are NOT in insertion order (which I did NOT expect/understand); array items ARE in insertion order.

Ultimately, I want to be able to refer to the hash in a form like:-

   @{$hash{$project}{$vitem}}

...realizing that this can be problematic, given that I'm using a couple of different Perl versions and the "keys on reference is experimental at..." issue is (not) present in some cases... but one thing at a time...(!)

Effectively, do something like:-

   for each project 
      output "Project: ", project
      for each vitem in the current project
         output "  VItem: ", vitem
         for each vitem segment
            output "    Segment: ", segment
         endfor
      endfor
   endfor

...but if you looked at the output, the "VItems" would be in the original order they were shown in the __DATA__ block (within in each project).

Oh.. and something I should have explained earlier... Running all this with Perl v5.20.2, build 2001, under 32-bit Win8.1 OR Perl v5.18.1, under Linux Kernel 3.14.55 (Puppy Linux 32-bit v6.3.2).

Hopefully, this helps explain the context some...