in reply to Perl - write data from hashes

This part of your code is rather strange:
if (exists($r1{$key})){
    $r1{$key} += $f[02];
}
else { 
    $r1{$key} += $f[02];
}

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You do exactly the same whether or not the key already exists in the hash. Therefore you can replace this simply by:
$r1{$key} += $f[02];

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CountZero

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Re^2: Perl - write data from hashes
by marinersk (Priest) on Oct 14, 2013 at 05:51 UTC
    Interesting.

    In older versions of Perl, I encountered the issue where attempting to add a value to an undefined hash element would generate a warning.

    I see under my modern version of Perl, this is not an issue: 

    #!/usr/bin/perl -w

use strict;

my $TEST_KEY = 'abc';
my $TEST_VAL = 5;

my %TestHash = ();

{
    print "-----[ Addition to undef ]---------------\n";
    %TestHash = ();
    $TestHash{$TEST_KEY} += $TEST_VAL;

    print "-----[ Addition testing for undef ]------\n";
    %TestHash = ();
    if (defined $TestHash{$TEST_KEY})
    {
        $TestHash{$TEST_KEY} += $TEST_VAL;
    }
    else
    {
        $TestHash{$TEST_KEY} = $TEST_VAL;
    }
}

exit;

__END__

C:\Steve\Dev\PerlMonks\P-2013-10-13@2339-HashUndef>hashtest.pl
-----[ Addition to undef ]---------------
-----[ Addition testing for undef ]------

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    I think -- not 100% sure, but I think -- I am happy about this.

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[d/l]

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