Re^4: sort hash of arrays of arrays

I'd like to sort the outer arrays of each hash item (1-4) separately, based on the second item of the inner arrays to finally have something like:

{
  1 => [
    [26, 27, 28],
    [16, 17, 18],
    [6, 7, 8],
    [1, 2, 3]
  ],
  2 => [
    [27, 28, 29],
    [17, 18, 19],
    [7, 8, 9],
    [2, 3, 4],
  ],
  3 => [
    [28, 29, 30],
    [18, 19, 20],
    [8, 9, 10],
    [3, 4, 5]
  ],
  4 => [
    [29, 30, 31],
    [19, 20, 21],
    [9, 10, 11],
    [4, 5, 6]
  ],
}
[download]

So for the first set, values 2, 7, 17 and 27 were compared to get the right order.
I hope this clarifies my problem.

Thanks

Comment on Re^4: sort hash of arrays of arrays Download Code

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Re^5: sort hash of arrays of arrays by BrowserUk (Patriarch) on Oct 31, 2012 at 16:05 UTC
Then you need to do one sort for each key in the hash like this: `@{ $hash{$_} } = sort{ $b->[1] <=> $a->[1] } @{ $hash{$_} } for keys % +hash;; pp \%hash;; { 1 => [[26, 27, 28], [16, 17, 18], [6, 7, 8], [1, 2, 3]], 2 => [[27, 28, 29], [17, 18, 19], [7, 8, 9], [2, 3, 4]], 3 => [[28, 29, 30], [18, 19, 20], [8, 9, 10], [3, 4, 5]], 4 => [[29, 30, 31], [19, 20, 21], [9, 10, 11], [4, 5, 6]], }` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. RIP Neil Armstrong	[reply] [d/l]
Re^6: sort hash of arrays of arrays by maladav (Initiate) on Oct 31, 2012 at 16:31 UTC
It's awesome, thank you! How does it work? Specifically, why does it need the `for keys %hash` part? How could I sort on the innermost elements (e.g. `[26, 27, 28]` to get `[28, 27, 26]`) using the same method? Thanks very much.	[reply] [d/l] [select]
Re^7: sort hash of arrays of arrays by BrowserUk (Patriarch) on Oct 31, 2012 at 16:44 UTC
How does it work? Specifically, why does it need the "for keys %hash" part? Because, as I said, you need to do one sort for each key. (I don't know how better to explain it than that. ) How could I sort on the innermost elements (e.g. `[26, 27, 28]` to get `[28, 27, 26]`) using the same method? Now you need to do one sort for each sub array, for each key, so you need nested loops: `for my $key ( keys %hash ) { for my $aref ( @{ $hash{ $key } } ) { @{ $aref } = sort { $b <=> $a } @{ $aref }; } } ;; pp \%hash;; { 1 => [[28, 27, 26], [18, 17, 16], [8, 7, 6], [3, 2, 1]], 2 => [[29, 28, 27], [19, 18, 17], [9, 8, 7], [4, 3, 2]], 3 => [[30, 29, 28], [20, 19, 18], [10, 9, 8], [5, 4, 3]], 4 => [[31, 30, 29], [21, 20, 19], [11, 10, 9], [6, 5, 4]], }` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. RIP Neil Armstrong	[reply] [d/l] [select]