So you say you have multiple values for certain keys.

key => value,value,value

[download]

This directly translates to Perl:

my %hash = (
   key => [ value, value, value ],
   ...
);

[download]

We call this a HoA, a hash of arrays as every value is another (anonymous) array-reference.

The creation of such a data structure is very easy with Perl as it has magic autovivification:

use Data::Dumper qw/Dumper/;

my %hash = ();

while( <DATA> ){
    chomp;

    my ($k,$v) = split /\s*:\s*/;

    push @{ $hash{ $k } } , $v
}

print Dumper( \%hash );
__DATA__
green : apple
yellow: banana
green : kiwi
red   : strawberry
green : mango
yellow: lemon

[download]

That's it. Perl is great. update: see perlref and perldata of course.

--
http://fruiture.de

In reply to Re: arrays from arrays by fruiture
in thread arrays from arrays by Anonymous Monk

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