Perl: Generating Arrays inside a Complex Hash

Question

In the quest to make my data more accessible, I want to store my tabulated data in a complex hash. I am trying to grow a \'HoHoHoA\' as the script loops over my data. As per

Answer 1

Here's how I would write a program to do that.

#! /usr/bin/env perl
use strict;
use warnings;
use 5.010; # for say and m'(?)'

use YAML;
use Data::Dump 'dump';

my(%data,%original);
while( my $line = <> ){
  next unless $line =~ m'
    ^ \s*
      (?   0?[1-9] | [12][0-9] | 3[0-1] ) /
      (? 0?[1-9] | 1[0-2] ) /
      (?  [0-9]{4} )
      \s+
      (?   0?[1-9] | 1[0-9] | 2[0-4] ) :
      (? 0?[1-9] | [1-5][0-9] ) :
      (? 0?[1-9] | [1-5][0-9] )
      \s+
      (? .* )
  'x;
  my @columns = split ' ', $+{columns};

  push @{
    $data{ $+{year}  }
         { $+{month} }
         { $+{day}   }
         { $+{hour}  }
  }, \@columns; # or [@columns]

  # If you insist on having it in that data structure you can do this:
  my $count = 1;
  my $date = "$+{day}/$+{month}/$+{year}";
  for my $column ( @columns ){
    my $col = 'COLUMN'.$count++;
    push @{ $original{$col}{$date}{$+{hour}} }, $column;
  }
}

say Dump \%data, \%original; # YAML
say dump \%data, \%original; # Data::Dump

Given this input

DATE       TIME     COLUMN1 COLUMN2 COLUMN3
09/06/2008 06:12:56 56.23   54.23   56.35
09/06/2008 06:42:56 56.73   55.28   54.52
09/06/2008 07:12:56 57.31   56.79   56.41
09/06/2008 07:42:56 58.24   57.30   58.86

Either "perl program.pl datafile" or "perl program.pl < datafile"

YAML

---
2008:
  06:
    09:
      06:
        -
          - 56.23
          - 54.23
          - 56.35
        -
          - 56.73
          - 55.28
          - 54.52
      07:
        -
          - 57.31
          - 56.79
          - 56.41
        -
          - 58.24
          - 57.30
          - 58.86
---
COLUMN1:
  09/06/2008:
    06:
      - 56.23
      - 56.73
    07:
      - 57.31
      - 58.24
COLUMN2:
  09/06/2008:
    06:
      - 54.23
      - 55.28
    07:
      - 56.79
      - 57.30
COLUMN3:
  09/06/2008:
    06:
      - 56.35
      - 54.52
    07:
      - 56.41
      - 58.86

Data::Dump

(
  {
    2008 => {
          "06" => {
                "09" => {
                      "06" => [["56.23", "54.23", "56.35"], ["56.73", "55.28", "54.52"]],
                      "07" => [["57.31", "56.79", "56.41"], ["58.24", "57.30", "58.86"]],
                    },
              },
        },
  },
  {
    COLUMN1 => {
                 "09/06/2008" => { "06" => ["56.23", "56.73"], "07" => ["57.31", "58.24"] },
               },
    COLUMN2 => {
                 "09/06/2008" => { "06" => ["54.23", "55.28"], "07" => ["56.79", "57.30"] },
               },
    COLUMN3 => {
                 "09/06/2008" => { "06" => ["56.35", "54.52"], "07" => ["56.41", "58.86"] },
               },
  },
)