Extract hash values without a loop

TJCooper has asked for the wisdom of the Perl Monks concerning the following question:

I have a data structure:

{
    A   [
        [0] 0.298024546928301,
        [1] 0.310437805395979,
        [2] 0.362849758185986,
        [3] 0.300927220244308,
        [4] 0.30014286502788
    ],
    C   [
        [0] 0.200608102102475,
        [1] 0.274657378132592,
        [2] 0.192625882771276,
        [3] 0.162815453143259,
        [4] 0.158490613195079
    ],
    G   [
        [0] 0.217826947179901,
        [1] 0.132847137086947,
        [2] 0.206439273801657,
        [3] 0.188858010150455,
        [4] 0.253229183805833
    ],
    T   [
        [0] 0.28354040378812,
        [1] 0.282057679385473,
        [2] 0.238085085241806,
        [3] 0.347398866718639,
        [4] 0.288136438478111
    ]
}
[download]

And I want to access all of the main values at once, and possibly store them in separate arrays, for example:

$arrayA = (0.298024546928301, 0.310437805395979, 0.362849758185986, 0.300927220244308, 0.30014286502788)

For the values attached to the 'A' key. I can do this either by iterating over the hash and pushing each value into an array or via:

$test{'A'}[0,1,2,3];

However the number of values is variable and i'd rather not have to specify 0,1,2,3,4,5 etc. but rather just a range based on a variable. However when I do:

$test{'A'}[0..$value];

or:

$test{'A'}[0..3];

It no longer works. Why is that and how can I accomplish this?

Comment on Extract hash values without a loop Select or Download Code

Replies are listed 'Best First'.
Re: Extract hash values without a loop by huck (Prior) on Oct 06, 2017 at 19:23 UTC
`my @arrayA = @{$test{'A'}};`	[reply] [d/l]
Re: Extract hash values without a loop by AnomalousMonk (Archbishop) on Oct 06, 2017 at 19:32 UTC
Some more examples: `c:\@Work\Perl\monks>perl -wMstrict -MData::Dump -le "my %test = ( 'A' => [ qw(foo one fee three four bar) ], 'T' => [ 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3 ], ); ;; dd \%test; ;; my $value = 3; my @ra = @{ $test{A} }[ 0 .. $value ]; dd \@ra; ;; my @rb = @{ $test{T} }[ reverse 1 .. 4 ]; dd \@rb; " { A => ["foo", "one", "fee", "three", "four", "bar"], T => ["0.9", "0.8", "0.7", "0.6", "0.5", "0.4", "0.3"], } ["foo", "one", "fee", "three"] ["0.5", "0.6", "0.7", "0.8"]` [download] Update: See perlref, perlreftut, perldsc. (Update: In perldsc, see especially COMMON MISTAKES.) Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re: Extract hash values without a loop by Anonymous Monk on Oct 06, 2017 at 19:26 UTC
`@{$test{A}}[0..3]`	[reply] [d/l]