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Re: arrays from arrays

by fruiture (Curate)
on Mar 07, 2003 at 17:15 UTC ( #241189=note: print w/replies, xml ) Need Help??


in reply to arrays from arrays

So you say you have multiple values for certain keys.

key => value,value,value

This directly translates to Perl:

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

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

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

--
http://fruiture.de

Replies are listed 'Best First'.
Re: Re: arrays from arrays
by Anonymous Monk on Mar 07, 2003 at 17:50 UTC

    Excellent, thanks for that, worked perfectly, even if I don't quite know how... will real up on Date::Dumper on Monday..

    Thanks.

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[erix]: or compile & run an instance as yourself (not user 'postgres')
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