in reply to sorting hash by a certain value (that it is in an array)

In complement to Corion's answer: Re: sorting hash by a certain value (that it is in an array)

Here is an example. You can use more complexe sorting method (see commented line: lc(...) cmp lc(...)) and optimized it with The Orcish Maneuver. 
#!/usr/bin/env perl

use strict;
use warnings;

my %books=(
    '34' => ['enlgish', 'dani M. rod', 54],
    '24' => ['spanish', 'ramk rovale', 41],
    '54' => ['enlgish', 'bob falicas', 17],
);


my @sorted_books = sort {
    $books{$a}->[1] cmp $books{$b}->[1]
    #lc($books{$a}->[1]) cmp lc($books{$b}->[1])
} keys %books;

print "@sorted_books";

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Update: print sorted books


for my $book_id (@sorted_books) {
    print "$book_id: ",join ", ",@{ $books{$book_id} };
    print "\n";
}

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Re^2: sorting hash by a certain value (that it is in an array)
by gooyava (Novice) on Jul 17, 2012 at 13:27 UTC
    this is not about sorting an array, it's about sorting an hash that has arrays in it. the example by brx created a new sorted array @sorted_books. I need the %books hash to be sorted as so: 
    %books=(
   '54' => ['enlgish', 'bob falicas', 17], 
   '34' => ['enlgish', 'dani M. rod', 54],
   '24' => ['spanish', 'ramk rovale', 41],
);

    [download]
    I don't see how the example by brx gives me that. when I print out the %books hash using this: 
    while (my($key, $value) = each(%books)){
    print "$key: $value\n";
}

    [download]
    I get the same unsorted result.
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      A hash is a different data structure than an array. Its advantage is that it allows arbitrary strings as keys instead of just a number. The disadvantage is that it can't be sorted. Read about "hash tables" on wikipedia if you want to know why.

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      Perhaps you could use Tie::IxHash? 
         my %unordered=(...);
   tie my %ordered, "Tie::IxHash";
   for my $key (sort {$unordered{$a}[1] cmp $unordered{$b}[1]} keys %$
+unordered) {
      $ordered{$key}=$unordered->{$key};
   };

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[d/l]
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