http://www.perlmonks.org?node_id=922476

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

I feel like I should know this already, but I don't. Is there a shorthand way to get a "column" slice of a 2D array? For example, given @a = ([2,4],[4,5],[8,6],[10,7]); how would I get (4,5,6,7) other than writing for $i (0..$#a) { @b = $a[$i][1] }?

TIA...

Steve

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Re: Column slice of a 2D array
by BrowserUk (Patriarch) on Aug 26, 2011 at 00:39 UTC
    Is there a shorthand way to get a "column" slice of a 2D array?

    Not really, but map maybe makes it a little clearer:

    @a = ([2,4],[4,5],[8,6],[10,7]);;
print map $_->[1], @a;;
4 5 6 7

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Re: Column slice of a 2D array
by ricDeez (Scribe) on Aug 26, 2011 at 04:02 UTC

    Or as a slight variation on BrowserUk's code: 

    use Modern::Perl;
use Data::Dumper;
my @a = ([2,4],[4,5],[8,6],[10,7]);
my @b;
push @b, $_->[1] for @a;
print Dumper \@b;

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    prints: 

    $VAR1 = [
          4,
          5,
          6,
          7
        ];

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