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

I have an array such as this : 
$Array1[0][0] = 10;
$Array1[0][1] = 15;
$Array1[1][0] = 20;
$Array1[1][1] = 30;
....
@Array2 = @Array1;
# Loop through @Array1 and make changes to it. After loop I want to ma
+ke reference to initial values that were stored in Array1 through use
+ of Array2.

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How can I copy Array1 (2 dimensional array) and use that copy after the loop the exact same way as I would trying to access items from the newly updated Array1 array? I tried @Array2 = @Array1 but any changes to Array1 are reflected in Array2. Should I use Storable::dclone? What would be the simpliest steps needed to copy the array and afterwards reference the exact same way as the modified Array1? Thanks in advance for any help.

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Re: Copying multi-dimensional array
by ikegami (Patriarch) on Apr 21, 2011 at 14:24 UTC
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Re: Copying multi-dimensional array
by wind (Priest) on Apr 21, 2011 at 14:43 UTC

    Yep, dclone is about as simple as you're going to find.

    use Storable qw(dclone);
use Data::Dumper;

use strict;
use warnings;

my @Array1 = ([10,15],[20,30]);

my $Array2 = dclone(\@Array1);

$Array1[0][1] = 71; # Does change translate?

print Dumper($Array2); # Nope

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      Thanks for the info guys. I added the following as well. 
      my @Array2 = @{ dclone(\@Array1) };

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Re: Copying multi-dimensional array
by anonymized user 468275 (Curate) on Apr 21, 2011 at 14:55 UTC
    YADA (Yet Another Dumper Approach): 
    use Data::Dumper;
my $VAR1; # must be this variable name
# ... populate @array1 here ...
eval Dumper( \@array1 );
my @array2 = @$VAR1;
# ... now array2 is copied at all levels into its own storage at all l
+evels

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    One world, one people

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